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Orders of magnitude (length)
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<h2 id="overview">Overview</h2> <table><tbody><tr><th rowspan="2">Scale</th><th colspan="2">Range (<a href="/facts/Metre/hPhzc1CV">m</a>)</th><th rowspan="2">Unit</th><th rowspan="2">Example items</th></tr><tr><th>≥</th><th><</th></tr><tr><td rowspan="3">Subatomic</td><td>–</td><td>0</td><td>–</td><td><a href="/facts/Gravitational_singularity/BptlItux">Gravitational singularity</a></td></tr><tr><td>10−36</td><td>10−33</td><td><a href="/facts/Planck_length/4o04JYdD">ℓP</a></td><td>Fixed value (not a range). <a href="/facts/Quantum_foam/3DtBeEFj">Quantum foam</a>, <a href="/facts/String_(physics)/3EtMw6n2">string</a></td></tr><tr><td>10−18</td><td>10−15</td><td><a href="/facts/Attometre/YzL1bHGX">am</a></td><td><a href="/facts/Proton/clCjepXP">Proton</a>, <a href="/facts/Neutron/oRCM1geb">neutron</a>, <a href="/facts/Pion/x5HamzG3">pion</a></td></tr><tr><td rowspan="3">Atomic to cellular</td><td>10−15</td><td>10−12</td><td><a href="/facts/Femtometre/9XzQ8UmR">fm</a></td><td><a href="/facts/Atomic_nucleus/orpIm5Xl">Atomic nucleus</a></td></tr><tr><td>10−12</td><td>10−9</td><td><a href="/facts/Picometre/Cb54mVBX">pm</a></td><td><a href="/facts/Wavelength/kcJU0ymz">Wavelength</a> of <a href="/facts/Gamma_ray/5Drf913J">gamma rays</a> and <a href="/facts/X-ray/wseP79cN">X-rays</a>, <a href="/facts/Hydrogen_atom/ncVpPbuE">hydrogen atom</a></td></tr><tr><td>10−9</td><td>10−6</td><td><a href="/facts/Nanometre/a98sjHyu">nm</a></td><td><a href="/facts/DNA/nB89Iauz">DNA</a> <a href="/facts/Helix/BqC4AKwL">helix</a>, <a href="/facts/Virus/mf88Bcbl">virus</a>, wavelength of <a href="/facts/Optical_spectrum/frPBh8o5">optical spectrum</a>, transistors used in CPUs</td></tr><tr><td rowspan="2">Cellular to human</td><td>10−6</td><td>10−3</td><td><a href="/facts/Micrometre/7eDFxD2L">μm</a></td><td><a href="/facts/Bacterium/wC8xSCsU">Bacterium</a>, <a href="/facts/Fog/mrIdyIc7">fog</a> water droplet, human <a href="/facts/Hair/L7vt9FL3">hair</a>'s diameter<a class="footnote-ref" id="fnref:1" href="#fn:1"><sup>1</sup></a></td></tr><tr><td>10−3</td><td>1</td><td><a href="/facts/Millimetre/25mdTXpa">mm</a></td><td><a href="/facts/Mosquito/u8hTMTfc">Mosquito</a>, <a href="/facts/Golf_ball/1r2Y3CEb">golf ball</a>, <a href="/facts/Domestic_cat/82d0y6D5">domestic cat</a>, <a href="/facts/Violin/0m2eLF3B">violin</a>, <a href="/facts/Football_(association_football)/SC2f6csg">football</a></td></tr><tr><td rowspan="2">Human to astronomical</td><td>1</td><td>103</td><td><a href="/facts/Metre/hPhzc1CV">m</a></td><td><a href="/facts/Piano/lRI60lQK">Piano</a>, <a href="/facts/Human/rlcTENsr">human</a>, <a href="/facts/Automobile/I1IsH8IK">automobile</a>, <a href="/facts/Sperm_whale/mBUge07C">sperm whale</a>, <a href="/facts/Association_football/yttjeD0D">football field</a>, <a href="/facts/Eiffel_Tower/IptQeofK">Eiffel Tower</a></td></tr><tr><td>103</td><td>106</td><td><a href="/facts/Kilometre/hdQp79QE">km</a></td><td><a href="/facts/Mount_Everest/hspjxkgv">Mount Everest</a>, length of <a href="/facts/Panama_Canal/Tau1ccDe">Panama Canal</a> and <a href="/facts/Trans-Siberian_Railway/nKn6Md9B">Trans-Siberian Railway</a>, larger <a href="/facts/Asteroid/g7Ulr1VB">asteroid</a></td></tr><tr><td rowspan="7">Astronomical</td><td>106</td><td>109</td><td>Mm</td><td>The <a href="/facts/Moon/zKHqEMPb">Moon</a>, Earth, one <a href="/facts/Light-second/0H0qncnG">light-second</a></td></tr><tr><td>109</td><td>1012</td><td>Gm</td><td><a href="/facts/Sun/CadPCVHh">Sun</a>, one <a href="/facts/Light-minute/0H0qncnG">light-minute</a>, <a href="/facts/Earth%27s_orbit/BGGCdFag">Earth's orbit</a></td></tr><tr><td>1012</td><td>1015</td><td>Tm</td><td>Orbits of <a href="/facts/Outer_planets/QIcLSazQ">outer planets</a>, <a href="/facts/Solar_System/QIcLSazQ">Solar System</a></td></tr><tr><td>1015</td><td>1018</td><td>Pm</td><td>A <a href="/facts/Light-year/IGc5NdQb">light-year</a>, the distance to <a href="/facts/Proxima_Centauri/6vSeytbA">Proxima Centauri</a></td></tr><tr><td>1018</td><td>1021</td><td>Em</td><td><a href="/facts/Spiral_arm/hRT2dtxJ">Galactic arm</a></td></tr><tr><td>1021</td><td>1024</td><td>Zm</td><td><a href="/facts/Milky_Way/ulF6lccN">Milky Way</a>, distance to <a href="/facts/Andromeda_Galaxy/MjmSLV6m">Andromeda Galaxy</a></td></tr><tr><td>1024</td><td>1027</td><td>Ym</td><td><a href="/facts/Huge-LQG/XGTJwRvR">Huge-LQG</a>, <a href="/facts/Hercules%E2%80%93Corona_Borealis_Great_Wall/kszfcMlc">Hercules–Corona Borealis Great Wall</a>, <a href="/facts/Observable_universe/CdTGMdsp">Observable universe</a></td></tr></tbody></table> <h2 id="detailed-list">Detailed list</h2> <p>To help compare different orders of magnitude, the following list describes various lengths between 1.6 × 10 − 35 {\displaystyle 1.6\times 10^{-35}} meters and 10 10 10 122 {\displaystyle 10^{10^{10^{122}}}} meters. </p> <h3>Subatomic scale</h3> <table><tbody><tr><th>Factor (<a href="/facts/Metre/hPhzc1CV">m</a>)</th><th>Multiple</th><th>Value</th><th>Item</th></tr><tr><td>0</td><td>0</td><td>0</td><td><a href="/facts/Gravitational_singularity/BptlItux">Singularity</a></td></tr><tr><td>10−35</td><td>1 <a href="/facts/Planck_length/4o04JYdD">Planck length</a></td><td>0.0000162 qm </td><td><a href="/facts/Planck_length/4o04JYdD">Planck length</a>; typical scale of hypothetical <a href="/facts/Loop_quantum_gravity/6Xueeoux">loop quantum gravity</a> or size of a hypothetical <a href="/facts/String_(physics)/3EtMw6n2">string</a> and of <a href="/facts/Brane/fPHTVchc">branes</a>; according to <a href="/facts/String_theory/HUJFIPYH">string theory</a>, lengths smaller than this do not make any <a href="/facts/Physics/a7aH2y08">physical</a> sense.<a class="footnote-ref" id="fnref:2" href="#fn:2"><sup>2</sup></a> <a href="/facts/Quantum_foam/3DtBeEFj">Quantum foam</a> is thought to exist at this scale.</td></tr><tr><td>10−24</td><td>1 yoctometer (<a href="/facts/Yoctometre/YzL1bHGX">ym</a>)</td><td>142 ym</td><td>Effective <a href="/facts/Cross_section_(physics)/lo014h2D">cross section</a> radius of 1 <a href="/facts/MeV/YMT1fqX9">MeV</a> <a href="/facts/Neutrino/yGWVfSg2">neutrinos</a><a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a></td></tr><tr><td rowspan="3">10−21</td><td rowspan="3">1 zeptometer (<a href="/facts/Zeptometre/YzL1bHGX">zm</a>)</td><td></td><td><a href="/facts/Preon/hK8F5UHe">Preons</a>, hypothetical particles proposed as subcomponents of quarks and leptons; the upper bound for the width of a <a href="/facts/Cosmic_string/Lx0K1u80">cosmic string</a> in string theory</td></tr><tr><td>7 zm</td><td>Effective cross section radius of high-energy <a href="/facts/Neutrino/yGWVfSg2">neutrinos</a><a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a></td></tr><tr><td>310 zm</td><td><a href="/facts/De_Broglie_wavelength/Rpszb8f1">De Broglie wavelength</a> of <a href="/facts/Protons/clCjepXP">protons</a> at the <a href="/facts/Large_Hadron_Collider/XWJCFSqT">Large Hadron Collider</a> (4 TeV as of 2012<a href="https://en.wikipedia.org/w/index.php?title=Orders_of_magnitude_(length)&action=edit">[update]</a>)</td></tr><tr><td rowspan="3">10−18</td><td rowspan="3">1 attometer (<a href="/facts/Attometre/YzL1bHGX">am</a>)</td><td rowspan="3"></td><td>Upper limit for the size of <a href="/facts/Quark/hwuuVkV5">quarks</a> and <a href="/facts/Electron/L0KBo5cW">electrons</a></td></tr><tr><td>Sensitivity of the <a href="/facts/LIGO/jX6jyJzM">LIGO</a> detector for <a href="/facts/Gravitational_wave/4XWN3NtG">gravitational waves</a><a class="footnote-ref" id="fnref:5" href="#fn:5"><sup>5</sup></a></td></tr><tr><td>Upper bound of the typical size range for "fundamental <a href="/facts/String_(physics)/3EtMw6n2">strings</a>"<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a></td></tr><tr><td>10−17</td><td>10 am</td><td></td><td>Range of the <a href="/facts/Weak_force/f6upmKMs">weak force</a></td></tr><tr><td>10−16</td><td>100 am</td><td>850 am</td><td>Approximate proton radius<a class="footnote-ref" id="fnref:7" href="#fn:7"><sup>7</sup></a></td></tr></tbody></table> <h3>Atomic to cellular scale</h3> <table><tbody><tr><th>Factor (<a href="/facts/Metre/hPhzc1CV">m</a>)</th><th>Multiple</th><th>Value</th><th>Item</th></tr><tr><td rowspan="5">10−15</td><td rowspan="5">1 femtometer (<a href="/facts/Femtometre/9XzQ8UmR">fm</a>, fermi)</td><td>1 fm</td><td>Approximate limit of the <a href="/facts/Gluon/t6YH8I21">gluon</a>-mediated <a href="/facts/Strong_interaction/JjRsKcLg">color force</a> between <a href="/facts/Quark/hwuuVkV5">quarks</a><a class="footnote-ref" id="fnref:8" href="#fn:8"><sup>8</sup></a><a class="footnote-ref" id="fnref:9" href="#fn:9"><sup>9</sup></a></td></tr><tr><td>1.5 fm</td><td>Effective cross section radius of an 11 MeV <a href="/facts/Proton/clCjepXP">proton</a><a class="footnote-ref" id="fnref:10" href="#fn:10"><sup>10</sup></a></td></tr><tr><td>2.81794 fm</td><td><a href="/facts/Classical_electron_radius/dU9jFS10">Classical electron radius</a><a class="footnote-ref" id="fnref:11" href="#fn:11"><sup>11</sup></a></td></tr><tr><td>3 fm</td><td>Approximate limit of the <a href="/facts/Meson/9R0kIc1q">meson</a>-mediated <a href="/facts/Strong_interaction/JjRsKcLg">nuclear binding force</a><a class="footnote-ref" id="fnref:12" href="#fn:12"><sup>12</sup></a><a class="footnote-ref" id="fnref:13" href="#fn:13"><sup>13</sup></a></td></tr><tr><td>750 to 822.25 fm</td><td>Longest <a href="/facts/Wavelength/kcJU0ymz">wavelength</a> of <a href="/facts/Gamma_ray/5Drf913J">gamma rays</a></td></tr><tr><td rowspan="4">10−12</td><td rowspan="4">1 picometer (<a href="/facts/Picometre/Cb54mVBX">pm</a>)</td><td>1.75 to 15 fm</td><td>Diameter range of the <a href="/facts/Atomic_nucleus/orpIm5Xl">atomic nucleus</a><a class="footnote-ref" id="fnref:14" href="#fn:14"><sup>14</sup></a><a class="footnote-ref" id="fnref:15" href="#fn:15"><sup>15</sup></a></td></tr><tr><td>1 pm</td><td>Distance between <a href="/facts/Atomic_nuclei/orpIm5Xl">atomic nuclei</a> in a <a href="/facts/White_dwarf/gIYlTtrC">white dwarf</a></td></tr><tr><td>2.4 pm</td><td><a href="/facts/Compton_wavelength/og2h1J2q">Compton wavelength</a> of <a href="/facts/Electron/L0KBo5cW">electron</a></td></tr><tr><td>5 pm</td><td>Wavelength of shortest <a href="/facts/X-ray/wseP79cN">X-rays</a></td></tr><tr><td rowspan="2">10−11</td><td rowspan="2">10 pm</td><td>28 pm</td><td>Radius of <a href="/facts/Helium/yRul93TG">helium</a> atom</td></tr><tr><td>53 pm</td><td><a href="/facts/Bohr_radius/vvP1lghl">Bohr radius</a> (radius of a <a href="/facts/Hydrogen_atom/ncVpPbuE">hydrogen atom</a>)</td></tr><tr><td rowspan="4">10−10</td><td rowspan="4">100 pm</td><td>100 pm</td><td>1 <a href="/facts/%C3%85ngstr%C3%B6m/T5mjdd97">ångström</a> (also <a href="/facts/Covalent_radius/gLzAFRTk">covalent radius</a> of <a href="/facts/Sulfur/IK0amTfM">sulfur</a> atom<a class="footnote-ref" id="fnref:16" href="#fn:16"><sup>16</sup></a>)</td></tr><tr><td>154 pm</td><td>Length of a typical <a href="/facts/Covalent_bond/EzMLf3Pz">covalent bond</a> (<a href="/facts/Carbon/ukrgQexo">C</a>–C)</td></tr><tr><td>280 pm</td><td>Average size of the <a href="/facts/Water/0lkXnJPK">water</a> molecule (actual lengths may vary)</td></tr><tr><td>500 pm</td><td>Width of <a href="/facts/Protein/Jxmagu3E">protein</a> <a href="/facts/Alpha_helix/7CESPIYJ">α helix</a></td></tr><tr><td rowspan="5">10−9</td><td rowspan="5">1 nanometer (<a href="/facts/Nanometre/a98sjHyu">nm</a>)</td><td>1 nm</td><td>Diameter of a <a href="/facts/Carbon_nanotube/atuDPPaG">carbon nanotube</a><a class="footnote-ref" id="fnref:17" href="#fn:17"><sup>17</sup></a> Diameter of smallest transistor gate (as of 2016)<a class="footnote-ref" id="fnref:18" href="#fn:18"><sup>18</sup></a></td></tr><tr><td>2 nm</td><td>Diameter of the <a href="/facts/DNA/nB89Iauz">DNA</a> helix<a class="footnote-ref" id="fnref:19" href="#fn:19"><sup>19</sup></a></td></tr><tr><td>2.5 nm</td><td>Smallest <a href="/facts/Microprocessor/Fx9CaQht">microprocessor</a> <a href="/facts/Transistor/Bmr8zwL0">transistor</a> <a href="/facts/Gate_(transistor)/TerYC6Nz">gate</a> oxide thickness (as of January 2007<a href="https://en.wikipedia.org/w/index.php?title=Orders_of_magnitude_(length)&action=edit">[update]</a>)</td></tr><tr><td>3.4 nm</td><td>Length of a <a href="/facts/DNA/nB89Iauz">DNA</a> <a href="/facts/Turn_(biochemistry)/GdVBHbo3">turn</a> (10 <a href="/facts/Base_pair/xmPpPQ9W">bp</a>)<a class="footnote-ref" id="fnref:20" href="#fn:20"><sup>20</sup></a></td></tr><tr><td>6–10 nm</td><td>Thickness of <a href="/facts/Cell_membrane/vAXSD0DT">cell membrane</a></td></tr><tr><td rowspan="4">10−8</td><td rowspan="4">10 nm</td><td>10 nm</td><td>Upper range of thickness of <a href="/facts/Cell_wall/DYXJVrnw">cell wall</a> in <a href="/facts/Gram_staining/E20u5av2">Gram</a>-negative <a href="/facts/Bacteria/wC8xSCsU">bacteria</a><a class="footnote-ref" id="fnref:21" href="#fn:21"><sup>21</sup></a></td></tr><tr><td>10 nm</td><td>As of 2016<a href="https://en.wikipedia.org/w/index.php?title=Orders_of_magnitude_(length)&action=edit">[update]</a>, the <a href="/facts/10_nanometre/h5qaJnz9">10 nanometer</a> was the smallest <a href="/facts/Semiconductor_device_fabrication/Jd23Mu1z">semiconductor device fabrication</a> <a href="/facts/Semiconductor_node/Jd23Mu1z">node</a><a class="footnote-ref" id="fnref:22" href="#fn:22"><sup>22</sup></a></td></tr><tr><td>40 nm</td><td>Extreme <a href="/facts/Ultraviolet/kncBUqn5">ultraviolet</a> wavelength</td></tr><tr><td>50 nm</td><td><a href="/facts/Flying_height/x2QWf5G7">Flying height</a> of the <a href="/facts/Disk_read-and-write_head/WdpxUpjK">head</a> of a <a href="/facts/Hard_disk/kekLSGSE">hard disk</a><a class="footnote-ref" id="fnref:23" href="#fn:23"><sup>23</sup></a></td></tr><tr><td rowspan="3">10−7</td><td rowspan="3">100 nm</td><td>121.6 nm</td><td>Wavelength of the <a href="/facts/Lyman-alpha_line/R5xVnKKW">Lyman-alpha line</a><a class="footnote-ref" id="fnref:24" href="#fn:24"><sup>24</sup></a></td></tr><tr><td>120 nm</td><td>Typical diameter of the <a href="/facts/Human_immunodeficiency_virus/ulY2rgzu">human immunodeficiency virus</a> (HIV)<a class="footnote-ref" id="fnref:25" href="#fn:25"><sup>25</sup></a></td></tr><tr><td>400–700 nm</td><td>Approximate wavelength range of <a href="/facts/Visible_light/jeofpMn4">visible light</a><a class="footnote-ref" id="fnref:26" href="#fn:26"><sup>26</sup></a></td></tr></tbody></table> <h3>Cellular to human scale</h3> <table><tbody><tr><th>Factor (<a href="/facts/Metre/hPhzc1CV">m</a>)</th><th>Multiple</th><th>Value</th><th>Item</th></tr><tr><td rowspan="3">10−6</td><td rowspan="3">1 micrometer (<a href="/facts/Micrometre/7eDFxD2L">μm</a>)<p>(also called 1 micron)</p></td><td>1–4 μm</td><td>Typical length of a bacterium<a class="footnote-ref" id="fnref:27" href="#fn:27"><sup>27</sup></a></td></tr><tr><td>4 μm</td><td>Typical diameter of <a href="/facts/Spider_silk/e1BwKC9S">spider silk</a><a class="footnote-ref" id="fnref:28" href="#fn:28"><sup>28</sup></a></td></tr><tr><td>7 μm</td><td>Typical size of a <a href="/facts/Red_blood_cell/Kggpq8Jh">red blood cell</a><a class="footnote-ref" id="fnref:29" href="#fn:29"><sup>29</sup></a></td></tr><tr><td rowspan="4">10−5</td><td rowspan="4">10 μm</td><td>10 μm</td><td>Typical size of a fog, mist, or cloud water droplet</td></tr><tr><td>10 μm</td><td>Width of <a href="/facts/Transistor/Bmr8zwL0">transistors</a> in the <a href="/facts/Intel_4004/kAoetjSU">Intel 4004</a>, the world's first commercial <a href="/facts/Microprocessor/Fx9CaQht">microprocessor</a></td></tr><tr><td>12 μm</td><td>Width of <a href="/facts/Acrylic_fiber/PPPJIEvw">acrylic fiber</a></td></tr><tr><td>17–181 μm</td><td>Width range of human hair<a class="footnote-ref" id="fnref:30" href="#fn:30"><sup>30</sup></a></td></tr><tr><td rowspan="3">10−4</td><td rowspan="3">100 μm</td><td>340 μm</td><td>Size of a <a href="/facts/Pixel/UzwBvXBV">pixel</a> on a 17-inch monitor with a resolution of 1024×768</td></tr><tr><td>560 μm</td><td>Thickness of the central area of a human <a href="/facts/Cornea/oKA6clQT">cornea</a><a class="footnote-ref" id="fnref:31" href="#fn:31"><sup>31</sup></a></td></tr><tr><td>750 μm</td><td>Maximum diameter of <i><a href="/facts/Thiomargarita_namibiensis/blkQKIYY">Thiomargarita namibiensis</a></i>, the second largest bacterium ever discovered</td></tr><tr><td rowspan="3">10−3</td><td rowspan="3">1 millimeter (<a href="/facts/Millimetre/25mdTXpa">mm</a>)</td><td>~5 mm</td><td>Length of an average <a href="/facts/Flea/hFLUFK24">flea</a> is 1–10 mm (usually <5 mm)<a class="footnote-ref" id="fnref:32" href="#fn:32"><sup>32</sup></a></td></tr><tr><td>2.54 mm</td><td>One-tenth inch; distance between pins in <a href="/facts/Dual_in-line_package/Qgu6Jave">DIP</a> (dual-inline-package) electronic components</td></tr><tr><td>5.70 mm</td><td>Diameter of the projectile in <a href="/facts/5.56%C3%9745mm_NATO/eT9ENFzY">5.56×45mm NATO</a> ammunition</td></tr><tr><td rowspan="3">10−2</td><td rowspan="3">1 centimeter (<a href="/facts/Centimetre/urPkBdGR">cm</a>)</td><td>20 mm</td><td>Approximate width of an adult human <a href="/facts/Finger/v2gDEpbp">finger</a></td></tr><tr><td>54 mm × 86 mm</td><td>Dimensions of a <a href="/facts/Credit_card/7pKSB5LD">credit card</a>, according to the <a href="/facts/ISO/IEC_7810_ID-1/ntfDju79">ISO/IEC 7810 ID-1</a> standard</td></tr><tr><td>73–75 mm</td><td>Diameter of a <a href="/facts/Baseball_(ball)/U2033ze4">baseball</a>, according to <a href="/facts/Major_League_Baseball/4WW9yef3">Major League Baseball</a> guidelines<a class="footnote-ref" id="fnref:33" href="#fn:33"><sup>33</sup></a></td></tr><tr><td rowspan="3">10−1</td><td rowspan="3">1 decimeter (<a href="/facts/Decimetre/Ww43QljM">dm</a>)</td><td>120 mm</td><td>Diameter of a <a href="/facts/Compact_disc/g51GRloc">compact disc</a></td></tr><tr><td>660 mm</td><td>Length of the longest <a href="/facts/Pine/HvMa9uc1">pine</a> cones, produced by the <a href="/facts/Sugar_pine/E75auBQk">sugar pine</a><a class="footnote-ref" id="fnref:34" href="#fn:34"><sup>34</sup></a></td></tr><tr><td>900 mm</td><td>Average length of a <a href="/facts/Rapier/f9VwMg22">rapier</a>, a <a href="/facts/Fencing/9h2HHTvy">fencing</a> sword<a class="footnote-ref" id="fnref:35" href="#fn:35"><sup>35</sup></a></td></tr></tbody></table> <h3>Human to astronomical scale</h3> <table><tbody><tr><th>Factor (<a href="/facts/Metre/hPhzc1CV">m</a>)</th><th>Multiple</th><th>Value</th><th>Item</th></tr><tr><td rowspan="3">1 (100)</td><td rowspan="3">1 meter (<a href="/facts/Metre/hPhzc1CV">m</a>)</td><td>1 m (exactly)</td><td>Since 2019, defined as the length of the path travelled by <a href="/facts/Light/jeofpMn4">light in a vacuum</a> during a time interval of 1/299,792,458 of a <a href="/facts/Second/jtFxnJXx">second</a>, where the second is defined by a hyperfine transition frequency of <a href="/facts/Caesium/dXKN1S5k">caesium</a>.</td></tr><tr><td>2.72 m</td><td>Height of <a href="/facts/Robert_Wadlow/sRJwyIJS">Robert Wadlow</a>, tallest-known human.<a class="footnote-ref" id="fnref:36" href="#fn:36"><sup>36</sup></a></td></tr><tr><td>8.38 m</td><td>Length of a London bus (<a href="/facts/AEC_Routemaster/55eAQ7vQ">AEC Routemaster</a>)</td></tr><tr><td rowspan="3">101</td><td rowspan="3">1 decameter (<a href="/facts/Decametre/2A3vssMs">dam</a>)</td><td>33 m</td><td>Length of the longest-known <a href="/facts/Blue_whale/CSlRTeCf">blue whale</a><a class="footnote-ref" id="fnref:37" href="#fn:37"><sup>37</sup></a></td></tr><tr><td>52 m</td><td>Height of the <a href="/facts/Niagara_Falls/xoxUleQq">Niagara Falls</a><a class="footnote-ref" id="fnref:38" href="#fn:38"><sup>38</sup></a></td></tr><tr><td>93.47 m</td><td>Height of the <a href="/facts/Statue_of_Liberty/TlymQ7JI">Statue of Liberty</a></td></tr><tr><td rowspan="4">102</td><td rowspan="4">1 hectometer (<a href="/facts/Hectometre/y4vg9uCK">hm</a>)</td><td>105 m</td><td>Length of a typical <a href="/facts/Association_football/yttjeD0D">football</a> field</td></tr><tr><td>137 m (147 m)</td><td>Height (present and original) of the <a href="/facts/Great_Pyramid_of_Giza/7p5HrMFb">Great Pyramid of Giza</a></td></tr><tr><td>300 m</td><td>Height of the <a href="/facts/Eiffel_Tower/IptQeofK">Eiffel Tower</a>, one of the famous monuments of Paris</td></tr><tr><td>979 m</td><td>Height of the <a href="/facts/Salto_Angel/77cutvDE">Salto Angel</a>, the world's highest free-falling waterfall (<a href="/facts/Venezuela/eX1qnkln">Venezuela</a>)</td></tr><tr><td rowspan="3">103</td><td rowspan="3">1 kilometer (<a href="/facts/Kilometre/hdQp79QE">km</a>)</td><td>2.3 km</td><td>Length of the <a href="/facts/Three_Gorges_Dam/LMs99ndW">Three Gorges Dam</a>, the largest <a href="/facts/Dam/BroJFhEI">dam</a> in the world<a class="footnote-ref" id="fnref:39" href="#fn:39"><sup>39</sup></a><a class="footnote-ref" id="fnref:40" href="#fn:40"><sup>40</sup></a></td></tr><tr><td>3.1 km</td><td>Narrowest width of the <a href="/facts/Strait_of_Messina/30mvgb0f">Strait of Messina</a>, separating <a href="/facts/Italy/tUf0PDYF">Italy</a> and <a href="/facts/Sicily/E6fug03z">Sicily</a></td></tr><tr><td>8.848 km</td><td>Height of <a href="/facts/Mount_Everest/hspjxkgv">Mount Everest</a>, the highest mountain on Earth</td></tr><tr><td rowspan="3">104</td><td rowspan="3">10 km</td><td>10.9 km</td><td>Depth of the <a href="/facts/Challenger_Deep/u70JRmWq">Challenger Deep</a> in the <a href="/facts/Mariana_Trench/FJB9X9nC">Mariana Trench</a>, the deepest-known point on Earth's surface</td></tr><tr><td>27 km</td><td>Circumference of the <a href="/facts/Large_Hadron_Collider/XWJCFSqT">Large Hadron Collider</a>, as of May 2010<a href="https://en.wikipedia.org/w/index.php?title=Orders_of_magnitude_(length)&action=edit">[update]</a> the largest and highest energy <a href="/facts/Particle_accelerator/Pkuc08xC">particle accelerator</a></td></tr><tr><td>42.195 km</td><td>Length of a <a href="/facts/Marathon/IP3eBrhS">marathon</a></td></tr><tr><td rowspan="5">105</td><td rowspan="5">100 km</td><td>100 km</td><td>The distance the <a href="/facts/IAU/GMFPImXo">IAU</a> considers to be the limit to <a href="/facts/Space/tq6LUM3C">space</a>, called the <a href="/facts/Karman_line/CfvQ3fbp">Karman line</a></td></tr><tr><td>163 km</td><td>Length of the <a href="/facts/Suez_Canal/1zYoNryp">Suez Canal</a>, connecting the <a href="/facts/Mediterranean_Sea/Vr2pzVbM">Mediterranean Sea</a> to the <a href="/facts/Red_Sea/0dKWSgEe">Red Sea</a></td></tr><tr><td>491 km</td><td>Length of the <a href="/facts/Pyrenees/YJ38kInj">Pyrenees</a>, the <a href="/facts/Mountain_range/L7vxtr7A">mountain range</a> separating <a href="/facts/Spain/bIyrB8EY">Spain</a> and <a href="/facts/France/CxIeIKM3">France</a></td></tr><tr><td>600km</td><td><a href="/facts/Thermosphere/uhG50e2V">Thermosphere</a> height</td></tr><tr><td>974.6 km</td><td>Greatest diameter of the dwarf planet <a href="/facts/Ceres_(dwarf_planet)/yIVEMYtG">Ceres</a>.<a class="footnote-ref" id="fnref:41" href="#fn:41"><sup>41</sup></a></td></tr><tr><td rowspan="9">106</td><td rowspan="9">1 megameter (<a href="/facts/Megametre/YzL1bHGX">Mm</a>)</td><td>2.38 Mm</td><td>Diameter of dwarf planet <a href="/facts/Pluto/egq7MBeR">Pluto</a>, formerly the smallest <a href="/facts/Planet/rbPjE6Bx">planet</a> category<a class="footnote-ref" id="fnref:42" href="#fn:42"><sup>42</sup></a> in the Solar System</td></tr><tr><td>3.48 Mm</td><td>Diameter of the <a href="/facts/Moon/zKHqEMPb">Moon</a></td></tr><tr><td>5.2 Mm</td><td>Typical distance covered by the winner of the <a href="/facts/24_Hours_of_Le_Mans/lotVMp31">24 Hours of Le Mans</a> automobile endurance race</td></tr><tr><td>6.259 Mm</td><td>Length of the <a href="/facts/Great_Wall_of_China/aXVq4FrH">Great Wall of China</a></td></tr><tr><td>6.371 Mm</td><td>Average <a href="/facts/Earth_radius/PVsf0g2I">radius of Earth</a></td></tr><tr><td>6.378 Mm</td><td>Equatorial radius of Earth</td></tr><tr><td>6.6 Mm</td><td>Approximate length of the two longest rivers, the <a href="/facts/Nile/vGoXVUFH">Nile</a> and the <a href="/facts/Amazon_River/Ha9AzJY5">Amazon</a></td></tr><tr><td>7.821 Mm</td><td>Length of the <a href="/facts/Trans-Canada_Highway/gu9BR2C6">Trans-Canada Highway</a></td></tr><tr><td>9.288 Mm</td><td>Length of the <a href="/facts/Trans-Siberian_Railway/nKn6Md9B">Trans-Siberian Railway</a>, longest in the world</td></tr></tbody></table> <h3>Astronomical scale</h3> <table><tbody><tr><th>Factor (<a href="/facts/Metre/hPhzc1CV">m</a>)</th><th>Multiple</th><th>Value</th><th>Item</th></tr><tr><td rowspan="3">107</td><td rowspan="3">10 Mm</td><td>12.756 Mm</td><td>Equatorial diameter of Earth</td></tr><tr><td>20.004 Mm</td><td>Length of a <a href="/facts/Meridian_(geography)/zdbk1YPt">meridian</a> on Earth (distance between Earth's poles along the surface)<a class="footnote-ref" id="fnref:43" href="#fn:43"><sup>43</sup></a></td></tr><tr><td>40.075 Mm</td><td>Length of Earth's <a href="/facts/Equator/CjaxbVaN">equator</a></td></tr><tr><td rowspan="3">108</td><td rowspan="3">100 Mm</td><td>142.984 Mm</td><td>Diameter of <a href="/facts/Jupiter/95m7XjMT">Jupiter</a></td></tr><tr><td>299.792 Mm</td><td>Distance traveled by light in vacuum in one second (a <a href="/facts/Light-second/0H0qncnG">light-second</a>, exactly 299,792,458 m by definition of the <a href="/facts/Speed_of_light/sKSQwdNx">speed of light</a>)</td></tr><tr><td>384.4 Mm</td><td><a href="/facts/Moon/zKHqEMPb">Moon</a>'s orbital distance from Earth</td></tr><tr><td rowspan="2">109</td><td rowspan="2">1 gigameter (<a href="/facts/Gigametre/YzL1bHGX">Gm</a>)</td><td>1.39 Gm</td><td>Diameter of the <a href="/facts/Sun/CadPCVHh">Sun</a></td></tr><tr><td>5.15 Gm</td><td>Greatest mileage ever recorded by a car (3.2 million miles by a 1966 <a href="/facts/Volvo_P1800/nT2ls7VM">Volvo P-1800S</a>)<a class="footnote-ref" id="fnref:44" href="#fn:44"><sup>44</sup></a></td></tr><tr><td>1010</td><td>10 Gm</td><td>18 Gm</td><td>Approximately one <a href="/facts/Light-minute/0H0qncnG">light-minute</a></td></tr><tr><td rowspan="1">1011</td><td rowspan="1">100 Gm</td><td>150 Gm</td><td>1 <a href="/facts/Astronomical_unit/gjsbu5xU">astronomical unit</a> (au); mean distance between Earth and Sun</td></tr><tr><td rowspan="5">1012</td><td rowspan="5">1 terameter (Tm)</td><td>1.3 Tm</td><td>Optical diameter of <a href="/facts/Betelgeuse/BsD9Ap7C">Betelgeuse</a></td></tr><tr><td>1.4 Tm</td><td>Orbital distance of <a href="/facts/Saturn/D54LcGJ9">Saturn</a> from Sun</td></tr><tr><td>2 Tm</td><td>Estimated optical diameter of <a href="/facts/VY_Canis_Majoris/pdF78cT2">VY Canis Majoris</a>, one of the <a href="/facts/List_of_largest_stars/XNsQIqwD">largest-known stars</a></td></tr><tr><td>5.9 Tm</td><td>Orbital distance of Pluto from the Sun</td></tr><tr><td>~ 7.5 Tm</td><td>Outer boundary of the <a href="/facts/Kuiper_belt/IvLzYp5P">Kuiper belt</a></td></tr><tr><td rowspan="4">1013</td><td rowspan="4">10 Tm</td><td></td><td>Diameter of the <a href="/facts/Solar_System/QIcLSazQ">Solar System</a> as a whole<a class="footnote-ref" id="fnref:45" href="#fn:45"><sup>45</sup></a></td></tr><tr><td>16.09 Tm</td><td>Total length of DNA molecules in all cells of an adult human body<a class="footnote-ref" id="fnref:46" href="#fn:46"><sup>46</sup></a></td></tr><tr><td>21.49 Tm</td><td>Distance of the <i><a href="/facts/Voyager_1/39jCxR9I">Voyager 1</a></i> spacecraft from Sun (as of Oct 2018<a href="https://en.wikipedia.org/w/index.php?title=Orders_of_magnitude_(length)&action=edit">[update]</a>), the farthest man-made object so far<a class="footnote-ref" id="fnref:47" href="#fn:47"><sup>47</sup></a></td></tr><tr><td>62.03 Tm</td><td>Estimated radius of the <a href="/facts/Event_horizon/KXH2ptnI">event horizon</a> of the <a href="/facts/Supermassive_black_hole/BcuTx8Q5">supermassive black hole</a> in <a href="/facts/NGC_4889/Ykq4QFqc">NGC 4889</a>, the largest-known <a href="/facts/Black_hole/1r2lmkcF">black hole</a> to date</td></tr><tr><td>1014</td><td>100 Tm</td><td>180 Tm</td><td>Size of the <a href="/facts/Debris_disk/ClIxTnge">debris disk</a> around the star <a href="/facts/51_Pegasi/8S6XgMo1">51 Pegasi</a><a class="footnote-ref" id="fnref:48" href="#fn:48"><sup>48</sup></a></td></tr><tr><td rowspan="2">1015</td><td rowspan="2">1 petameter (Pm)</td><td>~7.5 Pm</td><td>Supposed outer boundary of the <a href="/facts/Oort_cloud/wdP3VNxd">Oort cloud</a> (~ 50,000 au)</td></tr><tr><td>9.461 Pm</td><td>Distance traveled by light in vacuum in one year; at its current speed, <i>Voyager 1</i> would need 17,500 years to travel this distance</td></tr><tr><td rowspan="3">1016</td><td rowspan="3">10 Pm</td><td>30.857 Pm</td><td>1 <a href="/facts/Parsec/SwSsk57J">parsec</a></td></tr><tr><td>39.9 Pm</td><td>Distance to nearest star (<a href="/facts/Proxima_Centauri/6vSeytbA">Proxima Centauri</a>)</td></tr><tr><td>41.3 Pm</td><td>As of March 2013, distance to nearest discovered <a href="/facts/Extrasolar_planet/zjfmqfUf">extrasolar planet</a> (<a href="/facts/Alpha_Centauri_Bc/6BlySfIj">Alpha Centauri Bc</a>)</td></tr><tr><td rowspan="2">1017</td><td rowspan="2">100 Pm</td><td>193 Pm</td><td>As of October 2010, distance to nearest discovered extrasolar planet with potential to support life as presently defined by science (<a href="/facts/Gliese_581_d/4Jzo58Fy">Gliese 581 d</a>)</td></tr><tr><td>615 Pm</td><td>Approximate radius of humanity's radio bubble, caused by high-power TV broadcasts leaking through the atmosphere into outer space</td></tr><tr><td>1018</td><td>1 exameter (Em)</td><td>1.9 Em</td><td>Distance to nearby <a href="/facts/Solar_twin/KdMa9BIH">solar twin</a> (<a href="/facts/HIP_56948/ARhKTjpC">HIP 56948</a>), a star with properties virtually identical to the Sun<a class="footnote-ref" id="fnref:49" href="#fn:49"><sup>49</sup></a></td></tr><tr><td>1019</td><td>10 Em</td><td>9.46 Em</td><td>Average thickness of <a href="/facts/Milky_Way_Galaxy/ulF6lccN">Milky Way Galaxy</a><a class="footnote-ref" id="fnref:50" href="#fn:50"><sup>50</sup></a> (1,000 to 3,000 ly by <a href="/facts/Hydrogen_line/fQaWCT2t">21 cm observations</a><a class="footnote-ref" id="fnref:51" href="#fn:51"><sup>51</sup></a>)</td></tr><tr><td rowspan="1">1020</td><td>100 Em</td><td>113.5 Em</td><td>Thickness of <a href="/facts/Milky_Way_Galaxy/ulF6lccN">Milky Way Galaxy</a>'s gaseous disk<a class="footnote-ref" id="fnref:52" href="#fn:52"><sup>52</sup></a></td></tr><tr><td rowspan="6">1021</td><td rowspan="6">1 zettameter (Zm)</td></tr><tr><td>1.54 Zm</td><td>Distance to <a href="/facts/Supernova_1987a/zHyoUpBC">SN 1987A</a>, the most recent naked eye supernova</td></tr><tr><td>1.62 Zm</td><td>Distance to the <a href="/facts/Large_Magellanic_Cloud/7VYAehNa">Large Magellanic Cloud</a> (a <a href="/facts/Dwarf_galaxy/TKS7W9tA">dwarf galaxy</a> <a href="/facts/Orbit/nD2TPySG">orbiting</a> the <a href="/facts/Milky_Way/ulF6lccN">Milky Way</a>)</td></tr><tr><td>1.66 Zm</td><td>Distance to the <a href="/facts/Small_Magellanic_Cloud/jg9s2YCl">Small Magellanic Cloud</a> (another dwarf galaxy orbiting the Milky Way)</td></tr><tr><td>1.9 Zm</td><td>Diameter of galactic disk of <a href="/facts/Milky_Way_Galaxy/ulF6lccN">Milky Way Galaxy</a><a class="footnote-ref" id="fnref:53" href="#fn:53"><sup>53</sup></a><a class="footnote-ref" id="fnref:54" href="#fn:54"><sup>54</sup></a><a class="footnote-ref" id="fnref:55" href="#fn:55"><sup>55</sup></a><a class="footnote-ref" id="fnref:56" href="#fn:56"><sup>56</sup></a></td></tr><tr><td>6.15 Zm</td><td>Diameter of the low surface brightness disc halo of the giant spiral galaxy <a href="/facts/Malin_1/TePxKFkl">Malin 1</a></td></tr><tr><td rowspan="4">1022</td><td rowspan="4">10 Zm</td><td>13.25 Zm</td><td>Radius of the diffuse stellar halo of <a href="/facts/IC_1101/EyjpSSDX">IC 1101</a>, one of the largest-known galaxies</td></tr><tr><td>24 Zm</td><td>Distance to <a href="/facts/Andromeda_Galaxy/MjmSLV6m">Andromeda Galaxy</a></td></tr><tr><td>30.857 Zm</td><td>1 <a href="/facts/Megaparsec/SwSsk57J">megaparsec</a></td></tr><tr><td>50 Zm</td><td>Diameter of <a href="/facts/Local_Group/kjUefCLr">Local Group</a> of <a href="/facts/Galaxy/zCyUvEf7">galaxies</a></td></tr><tr><td>1023</td><td>100 Zm</td><td>300–600 Zm</td><td>Distance to <a href="/facts/Virgo_cluster/dBsDKTzT">Virgo cluster</a> of <a href="/facts/Galaxy/zCyUvEf7">galaxies</a></td></tr><tr><td rowspan="4">1024</td><td rowspan="4">1 yottameter (Ym)</td><td>2.19 Ym</td><td>Diameter of the <a href="/facts/Local_Supercluster/kUNskKbo">Local Supercluster</a> and the largest voids and filaments</td></tr><tr><td>2.8 Ym</td><td><a href="/facts/End_of_Greatness/CdTGMdsp">End of Greatness</a></td></tr><tr><td>~5 Ym</td><td>Diameter of the <a href="/facts/Horologium_Supercluster/kcuYKgwt">Horologium Supercluster</a><a class="footnote-ref" id="fnref:57" href="#fn:57"><sup>57</sup></a></td></tr><tr><td>9.461 Ym</td><td>Diameter of the <a href="/facts/Pisces%E2%80%93Cetus_Supercluster_Complex/x0k4DRJa">Pisces–Cetus Supercluster Complex</a>, the supercluster complex which includes Earth</td></tr><tr><td rowspan="3">1025</td><td rowspan="3">10 Ym</td><td>13 Ym</td><td>Length of the <a href="/facts/Sloan_Great_Wall/ISF27bp0">Sloan Great Wall</a>, a giant wall of galaxies (<a href="/facts/Galactic_filament/MFPWn8pS">galactic filament</a>)<a class="footnote-ref" id="fnref:58" href="#fn:58"><sup>58</sup></a></td></tr><tr><td>30.857 Ym</td><td>1 <a href="/facts/Gigaparsec/SwSsk57J">gigaparsec</a></td></tr><tr><td>37.84 Ym</td><td>Length of the <a href="/facts/Huge-LQG/XGTJwRvR">Huge-LQG</a>, a group of 73 <a href="/facts/Quasar/HS96328l">quasars</a></td></tr><tr><td rowspan="3">1026</td><td rowspan="3">100 Ym</td><td>95 Ym</td><td>Estimated <a href="/facts/Distance_measures_(cosmology)/EYsRSlep">light travel distance</a> to certain <a href="/facts/Quasars/HS96328l">quasars</a>. Length of the <a href="/facts/Hercules%E2%80%93Corona_Borealis_Great_Wall/kszfcMlc">Hercules–Corona Borealis Great Wall</a>, a colossal wall of galaxies, the largest and the most massive structure in the observable universe as of 2014</td></tr><tr><td>127 Ym</td><td>Estimated light travel distance to <a href="/facts/GN-z11/XABxPf3A">GN-z11</a>, the <a href="/facts/List_of_the_most_distant_astronomical_objects/xutYjJn3">most distant object</a> ever observed</td></tr><tr><td>870 Ym</td><td>Approximate diameter (<a href="/facts/Comoving_distance/55cYbfbY">comoving distance</a>) of the <a href="/facts/Visible_universe/CdTGMdsp">visible universe</a><a class="footnote-ref" id="fnref:59" href="#fn:59"><sup>59</sup></a></td></tr><tr><td>1027</td><td>1 Rm</td><td>1.2 Rm</td><td>Lower bound of the (possibly infinite) radius of the universe, if it is a <a href="/facts/3-sphere/u67nImpY">3-sphere</a>, according to one estimate using the <a href="/facts/Wilkinson_Microwave_Anisotropy_Probe/UUJWfy0U">WMAP</a> data at 95% confidence<a class="footnote-ref" id="fnref:60" href="#fn:60"><sup>60</sup></a> It equivalently implies that there are at minimum 21 <a href="/facts/Particle_horizon/sxfNTy8E">particle horizon</a>-sized volumes in the universe.</td></tr><tr><td> 10 10 115 {\displaystyle 10^{10^{115}}} <a class="footnote-ref" id="fnref:61" href="#fn:61"><sup>61</sup></a></td><td> 10 10 115 {\displaystyle 10^{10^{115}}} m</td><td> 10 10 115 {\displaystyle 10^{10^{115}}} m</td><td>According to the laws of probability, the distance one must travel until one encounters a volume of space identical to our <a href="/facts/Observable_universe/CdTGMdsp">observable universe</a> with conditions identical to our own.<a class="footnote-ref" id="fnref:62" href="#fn:62"><sup>62</sup></a></td></tr><tr><td> 10 10 10 122 {\displaystyle 10^{10^{10^{122}}}} </td><td> 10 10 10 122 {\displaystyle 10^{10^{10^{122}}}} m</td><td> 10 10 10 122 {\displaystyle 10^{10^{10^{122}}}} m</td><td>Maximum size of universe after <a href="/facts/Inflation_(cosmology)/SujXx3aD">cosmological inflation</a>, implied by one resolution of the <a href="/facts/Hartle%E2%80%93Hawking_state/hdzWGTGB">No-Boundary Proposal</a><a class="footnote-ref" id="fnref:63" href="#fn:63"><sup>63</sup></a></td></tr></tbody></table> <h2 id="1-quectometer-and-less">1 quectometer and less</h2> <p>The <i>quectometre</i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>qm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 10−30 <a href="/facts/Metre/hPhzc1CV">metres</a>. To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> shorter than 10−30 <a href="/facts/Metre/hPhzc1CV">m</a> (1 qm). </p> <ul><li>1.6 × 10−5 quectometers (1.6 × 10−35 meters) – the <a href="/facts/Planck_length/4o04JYdD">Planck length</a> (Measures of distance shorter than this do not make physical sense, according to current theories of <a href="/facts/Physics/a7aH2y08">physics</a>.)</li> <li>1 qm – 1 quectometer, the smallest named subdivision of the meter in the <a href="/facts/SI_base_unit/M7PsTWg4">SI base unit</a> of length, one nonillionth of a meter.<a class="footnote-ref" id="fnref:64" href="#fn:64"><sup>64</sup></a></li></ul> <h2 id="1-rontometer">1 rontometer</h2> <p>The <i>rontometre</i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>rm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 10−27 <a href="/facts/Metre/hPhzc1CV">metres</a>. </p> <ul><li>1 rm – 1 rontometer, a subdivision of the meter in the <a href="/facts/SI_base_unit/M7PsTWg4">SI base unit</a> of length, one octillionth of a meter.<a class="footnote-ref" id="fnref:65" href="#fn:65"><sup>65</sup></a></li></ul> <h2 id="10-rontometers">10 rontometers</h2> <ul><li>10 rm – the length of one side of a square whose area is one <a href="/facts/List_of_humorous_units_of_measurement/57ANtRko">shed</a>, a unit of <a href="/facts/Cross_section_(physics)/lo014h2D">target cross section</a> used in <a href="/facts/Nuclear_physics/fzQbt1aF">nuclear physics</a></li></ul> <h2 id="1-yoctometer">1 yoctometer</h2> <p> The <i>yoctometre</i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>ym</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 10−24 <a href="/facts/Metre/hPhzc1CV">metres</a>. </p> <ul><li>2 ym – the effective cross-section radius of 1 <a href="/facts/MeV/YMT1fqX9">MeV</a> <a href="/facts/Neutrino/yGWVfSg2">neutrinos</a> as measured by <a href="/facts/Clyde_Cowan/kdySD9zb">Clyde Cowan</a> and <a href="/facts/Frederick_Reines/sdWH4hNg">Frederick Reines</a>.<a class="footnote-ref" id="fnref:66" href="#fn:66"><sup>66</sup></a></li></ul> <h2 id="1-zeptometer">1 zeptometer</h2> <p>The <i>zeptometre</i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>zm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 10−21 <a href="/facts/Metre/hPhzc1CV">metres</a>. To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> between 10−21 <a href="/facts/Metre/hPhzc1CV">m</a> and 10−20 m (1 zm and 10 zm). </p> <ul><li>2 zm – the upper bound for the width of a <a href="/facts/Cosmic_string/Lx0K1u80">cosmic string</a> in string theory.</li> <li>2 zm – radius of effective <a href="/facts/Cross_section_(physics)/lo014h2D">cross section</a> for a <a href="/facts/Orders_of_magnitude_(energy)/Q3lDvBlS">20</a> <a href="/facts/GeV/YMT1fqX9">GeV</a> <a href="/facts/Neutrino/yGWVfSg2">neutrino</a> scattering off a <a href="/facts/Nucleon/6fguU9Xk">nucleon</a><a class="footnote-ref" id="fnref:67" href="#fn:67"><sup>67</sup></a></li> <li>7 zm – radius of effective cross section for a <a href="/facts/Orders_of_magnitude_(energy)/Q3lDvBlS">250</a>[<i>broken anchor</i>] GeV neutrino scattering off a nucleon<a class="footnote-ref" id="fnref:68" href="#fn:68"><sup>68</sup></a></li></ul> <h2 id="10-zeptometers">10 zeptometers</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> between 10−20 <a href="/facts/Metre/hPhzc1CV">m</a> and 10−19 m (10 <a href="/facts/Zeptometre/YzL1bHGX">zm</a> and 100 zm). </p> <h2 id="100-zeptometers">100 zeptometers</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists lengths between 10−19 <a href="/facts/Metre/hPhzc1CV">m</a> and 10−18 m (100 <a href="/facts/Zeptometre/YzL1bHGX">zm</a> and 1 <a href="/facts/Attometre/YzL1bHGX">am</a>). </p> <ul><li>177 zm – <a href="/facts/De_Broglie_wavelength/Rpszb8f1">de Broglie wavelength</a> of <a href="/facts/Protons/clCjepXP">protons</a> at the <a href="/facts/Large_Hadron_Collider/XWJCFSqT">Large Hadron Collider</a> (7 TeV as of 2010)</li></ul> <h2 id="1-attometer">1 attometer</h2> <p>The <i>attometre</i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>am</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 10−18 <a href="/facts/Metre/hPhzc1CV">metres</a>. To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> between 10−18 <a href="/facts/Metre/hPhzc1CV">m</a> and 10−17 m (1 am and 10 am). </p> <ul><li>1 am – sensitivity of the <a href="/facts/LIGO/jX6jyJzM">LIGO</a> detector for <a href="/facts/Gravitational_wave/4XWN3NtG">gravitational waves</a></li> <li>1 am – upper limit for the size of <a href="/facts/Quark/hwuuVkV5">quarks</a> and <a href="/facts/Electron/L0KBo5cW">electrons</a></li></ul> <h2 id="10-attometers">10 attometers</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> between 10−17 <a href="/facts/Metre/hPhzc1CV">m</a> and 10−16 m (10 <a href="/facts/Attometre/YzL1bHGX">am</a> and 100 am). </p> <ul><li>10–100 am – range of the weak force<a class="footnote-ref" id="fnref:69" href="#fn:69"><sup>69</sup></a></li> <li>86 am – charge radius of a <a href="/facts/Eta_meson/Nwaa16Cm">Bottom eta meson</a><a class="footnote-ref" id="fnref:70" href="#fn:70"><sup>70</sup></a></li></ul> <h2 id="100-attometers">100 attometers</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists lengths between 10−16 <a href="/facts/Metre/hPhzc1CV">m</a> and 10−15 m (100 <a href="/facts/Attometre/YzL1bHGX">am</a> and 1 <a href="/facts/Femtometre/9XzQ8UmR">fm</a>). </p> <ul><li>831 am – approximate proton radius<a class="footnote-ref" id="fnref:71" href="#fn:71"><sup>71</sup></a><a class="footnote-ref" id="fnref:72" href="#fn:72"><sup>72</sup></a></li></ul> <h2 id="1-femtometer-or-1-fermi">1 femtometer (or 1 fermi)</h2> <p>The <i><a href="/facts/Femtometre/9XzQ8UmR">femtometre</a></i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>fm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 10−15 <a href="/facts/Metre/hPhzc1CV">metres</a>. In <a href="/facts/Particle_physics/YgIuyj2t">particle physics</a>, this unit is sometimes called a <a href="/facts/Fermi_(unit)/9XzQ8UmR">fermi</a>, also with abbreviation "fm". To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> between 10−15 <a href="/facts/Metre/hPhzc1CV">meters</a> and 10−14 meters (1 femtometer and 10 fm). </p> <ul><li>1 fm – diameter of a <a href="/facts/Neutron/oRCM1geb">neutron</a>, approximate range-limit of the <a href="/facts/Strong_interaction/JjRsKcLg">color force</a> carried between <a href="/facts/Quark/hwuuVkV5">quarks</a> by <a href="/facts/Gluon/t6YH8I21">gluons</a><a class="footnote-ref" id="fnref:73" href="#fn:73"><sup>73</sup></a><a class="footnote-ref" id="fnref:74" href="#fn:74"><sup>74</sup></a></li> <li>1.5 fm – diameter of the <a href="/facts/Cross_section_(physics)/lo014h2D">scattering cross section</a> of an 11 <a href="/facts/Electron_volt/YMT1fqX9">MeV</a> <a href="/facts/Proton/clCjepXP">proton</a> with a target proton<a class="footnote-ref" id="fnref:75" href="#fn:75"><sup>75</sup></a></li> <li>1.75 fm – the effective charge diameter of a <a href="/facts/Proton/clCjepXP">proton</a><a class="footnote-ref" id="fnref:76" href="#fn:76"><sup>76</sup></a></li> <li>2.81794 fm – <a href="/facts/Classical_electron_radius/dU9jFS10">classical electron radius</a><a class="footnote-ref" id="fnref:77" href="#fn:77"><sup>77</sup></a></li> <li>3 fm – approximate range-limit of the <a href="/facts/Strong_interaction/JjRsKcLg">nuclear binding force</a> mediated by <a href="/facts/Meson/9R0kIc1q">mesons</a><a class="footnote-ref" id="fnref:78" href="#fn:78"><sup>78</sup></a><a class="footnote-ref" id="fnref:79" href="#fn:79"><sup>79</sup></a></li> <li>7 fm – the radius of the effective scattering cross section for a gold nucleus scattering a <a href="/facts/Orders_of_magnitude_(energy)/Q3lDvBlS">6</a>[<i>broken anchor</i>] <a href="/facts/Electron_volt/YMT1fqX9">MeV</a> <a href="/facts/Alpha_particle/dzNMs9WP">alpha particle</a> over 140 degrees<a class="footnote-ref" id="fnref:80" href="#fn:80"><sup>80</sup></a></li></ul> <h2 id="10-femtometers">10 femtometers</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> between 10−14 <a href="/facts/Metre/hPhzc1CV">m</a> and 10−13 m (10 <a href="/facts/Femtometre/9XzQ8UmR">fm</a> and 100 fm). </p> <ul><li>1.75 to 15 fm – diameter range of the <a href="/facts/Atomic_nucleus/orpIm5Xl">atomic nucleus</a></li> <li>10 fm – the length of one side of a square whose area is one <a href="/facts/Barn_(unit)/0yCEtKJ9">barn</a> (10−28 m2), a unit of <a href="/facts/Cross_section_(physics)/lo014h2D">target cross section</a> used in <a href="/facts/Nuclear_physics/fzQbt1aF">nuclear physics</a></li> <li>30.8568 fm – 1 quectoparsec (10−30 <a href="/facts/Parsecs/SwSsk57J">parsecs</a>)</li></ul> <h2 id="100-femtometers">100 femtometers</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists lengths between 10−13 <a href="/facts/Metre/hPhzc1CV">m</a> and 10−12 m (100 <a href="/facts/Femtometre/9XzQ8UmR">fm</a> and 1 <a href="/facts/Picometre/Cb54mVBX">pm</a>). </p> <ul><li>570 fm – typical distance from the atomic nucleus of the two innermost electrons (electrons in the <i>1s</i> shell) in the <a href="/facts/Uranium/n2sGWBzU">uranium</a> atom, the heaviest naturally-occurring atom</li></ul> <h2 id="1-picometer">1 picometer</h2> <p>The <i><a href="/facts/Picometre/Cb54mVBX">picometre</a></i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>pm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 10−12 <a href="/facts/Metre/hPhzc1CV">metres</a> (1/1000000000000 m = 0.000000000001 m). To help compare different <a href="/facts/Order_of_magnitude/cWzRP2dM">orders of magnitude</a> this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> between 10−12 and 10−11 m (1 pm and 10 pm). </p> <ul><li>1 pm – distance between <a href="/facts/Atomic_nuclei/orpIm5Xl">atomic nuclei</a> in a <a href="/facts/White_dwarf/gIYlTtrC">white dwarf</a></li> <li>1 pm – reference value of particle displacement in acoustics<a class="footnote-ref" id="fnref:81" href="#fn:81"><sup>81</sup></a></li> <li>2.4 pm – the <a href="/facts/Compton_wavelength/og2h1J2q">Compton wavelength</a> of an <a href="/facts/Electron/L0KBo5cW">electron</a></li> <li>5 pm – shorter <a href="/facts/X-ray/wseP79cN">X-ray</a> wavelengths (approx.)</li></ul> <h2 id="10-picometers">10 picometers</h2> <p>To help compare different <a href="/facts/Order_of_magnitude/cWzRP2dM">orders of magnitude</a> this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> between 10−11 and 10−10 <a href="/facts/Metre/hPhzc1CV">m</a> (10 pm and 100 pm). </p> <ul><li>25 pm – approximate radius of a helium atom, the smallest neutral atom<a class="footnote-ref" id="fnref:82" href="#fn:82"><sup>82</sup></a><a class="footnote-ref" id="fnref:83" href="#fn:83"><sup>83</sup></a></li> <li>30.8568 pm – 1 rontoparsec</li> <li>50 pm – radius of a hydrogen atom</li> <li>50 pm – <a href="/facts/Bohr_radius/vvP1lghl">bohr radius</a>: approximate radius of a hydrogen atom</li> <li>~50 pm – best resolution of a <a href="/facts/High-resolution_transmission_electron_microscopy/L7B2oHyr">high-resolution transmission electron microscope</a></li> <li>60 pm – radius of a carbon atom</li> <li>93 pm – length of a <a href="/facts/Diatomic_carbon/T5UcMAev">diatomic carbon</a> molecule</li> <li>96 pm – H–O bond length in a <a href="/facts/Water/0lkXnJPK">water</a> molecule</li></ul> <h2 id="100-picometers">100 picometers</h2> <p>To help compare different <a href="/facts/Order_of_magnitude/cWzRP2dM">orders of magnitude</a> this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> between 10−10 and 10−9 <a href="/facts/Metre/hPhzc1CV">m</a> (100 pm and 1 nm; 1 <a href="/facts/Angstrom/T5mjdd97">Å</a> and 10 Å). </p> <ul><li>100 pm – 1 <a href="/facts/%C3%85ngstr%C3%B6m/T5mjdd97">ångström</a></li> <li>100 pm – <a href="/facts/Covalent_radius/gLzAFRTk">covalent radius</a> of <a href="/facts/Sulfur/IK0amTfM">sulfur</a> atom<a class="footnote-ref" id="fnref:84" href="#fn:84"><sup>84</sup></a></li> <li>120 pm – <a href="/facts/Van_der_Waals_radius/PNoSTW41">van der Waals radius</a> of a neutral <a href="/facts/Hydrogen/BoYHjl0J">hydrogen</a> atom<a class="footnote-ref" id="fnref:85" href="#fn:85"><sup>85</sup></a></li> <li>120 pm – radius of a gold atom</li> <li>126 pm – covalent radius of <a href="/facts/Ruthenium/uzCm4ufn">ruthenium</a> atom</li> <li>135 pm – covalent radius of <a href="/facts/Technetium/MGYWNI5d">technetium</a> atom</li> <li>150 pm – length of a typical <a href="/facts/Covalent_bond/EzMLf3Pz">covalent bond</a> (<a href="/facts/Carbon/ukrgQexo">C</a>–C)</li> <li>153 pm – covalent radius of <a href="/facts/Silver/xXe41BGg">silver</a> atom</li> <li>155 pm – covalent radius of <a href="/facts/Zirconium/y7gsoQFz">zirconium</a> atom</li> <li>175 pm – covalent radius of <a href="/facts/Thulium/G2905xhd">thulium</a> atom</li> <li>200 pm – highest resolution of a typical <a href="/facts/Electron_microscope/XtaBktwF">electron microscope</a><a class="footnote-ref" id="fnref:86" href="#fn:86"><sup>86</sup></a></li> <li>225 pm – covalent radius of <a href="/facts/Caesium/dXKN1S5k">caesium</a> atom</li> <li>280 pm – average size of the <a href="/facts/Water/0lkXnJPK">water</a> molecule</li> <li>298 pm – radius of a <a href="/facts/Caesium/dXKN1S5k">caesium</a> atom, <a href="/facts/Atomic_radius/0mQaIJX9">calculated to be</a> the largest atomic radius</li> <li>340 pm – thickness of single layer <a href="/facts/Graphene/QDGUBaPt">graphene</a></li> <li>356.68 pm – width of <a href="/facts/Diamond/IBUdnd1y">diamond</a> <a href="/facts/Unit_cell/znygJqdx">unit cell</a></li> <li>403 pm – width of <a href="/facts/Lithium_fluoride/ujl6o884">lithium fluoride</a> unit cell</li> <li>500 pm – Width of <a href="/facts/Protein/Jxmagu3E">protein</a> <a href="/facts/Alpha_helix/7CESPIYJ">α helix</a></li> <li>543 pm – silicon lattice spacing</li> <li>560 pm – width of <a href="/facts/Sodium_chloride/MWcXl3Mb">sodium chloride</a> unit cell</li> <li>700 pm – width of <a href="/facts/Glucose/oUSkoLCD">glucose</a> molecule</li> <li>700 pm – diameter of a <a href="/facts/Buckyball/F0VebtPK">buckyball</a><a class="footnote-ref" id="fnref:87" href="#fn:87"><sup>87</sup></a></li> <li>780 pm – mean width of <a href="/facts/Quartz/4n86tE2G">quartz</a> unit cell</li> <li>820 pm – mean width of <a href="/facts/Ice/BGvkKFjD">ice</a> unit cell</li> <li>900 pm – mean width of <a href="/facts/Coesite/uQEYMrnD">coesite</a> unit cell</li></ul> <h2 id="1-nanometer">1 nanometer</h2> <p>The <i><a href="/facts/Nanometre/a98sjHyu">nanometre</a></i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>nm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 10−9 <a href="/facts/Metre/hPhzc1CV">metres</a> (1/1000000000 m = 0.000000001 m). To help compare different <a href="/facts/Order_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists lengths between 10−9 and 10−8 m (1 nm and 10 nm). </p> <ul><li>1 nm – diameter of a <a href="/facts/Carbon_nanotube/atuDPPaG">carbon nanotube</a></li> <li>1 nm – roughly the length of a <a href="/facts/Sucrose/7y1ke94L">sucrose</a> molecule, calculated by <a href="/facts/Albert_Einstein/CNTet8qu">Albert Einstein</a></li> <li>2.3 nm – length of a <a href="/facts/Phospholipid/u6GhNCF5">phospholipid</a></li> <li>2.3 nm – smallest <a href="/facts/Gate_(transistor)/TerYC6Nz">gate</a> oxide thickness in <a href="/facts/Microprocessor/Fx9CaQht">microprocessors</a></li> <li>3 nm – width of a <a href="/facts/DNA/nB89Iauz">DNA</a> helix</li> <li>3 nm – <a href="/facts/Flying_height/x2QWf5G7">flying height</a> of the <a href="/facts/Disk_read-and-write_head/WdpxUpjK">head</a> of a <a href="/facts/Hard_disk/kekLSGSE">hard disk</a></li> <li>3 nm – the <a href="/facts/3_nm_process/zR3mn68L">average half-pitch of a memory cell manufactured circa 2022</a></li> <li>3.4 nm – length of a DNA <a href="/facts/Turn_(biochemistry)/GdVBHbo3">turn</a> (10 <a href="/facts/Base_pair/xmPpPQ9W">bp</a>)</li> <li>3.8 nm – size of an <a href="/facts/Albumin/gDmSgAH2">albumin</a> molecule</li> <li>5 nm – size of the gate length of a 16 nm processor</li> <li>5 nm – the <a href="/facts/5_nm_process/5NndITJ3">average half-pitch of a memory cell manufactured circa 2019–2020</a></li> <li>6 nm – length of a <a href="/facts/Phospholipid/u6GhNCF5">phospholipid</a> bilayer</li> <li>6–10 nm – thickness of cell membrane</li> <li>6.8 nm – width of a <a href="/facts/Haemoglobin/RsD1MzYA">haemoglobin</a> molecule</li> <li>7 nm – diameter of <a href="/facts/Microfilament/TR7qU9Jv">actin filaments</a></li> <li>7 nm – the <a href="/facts/7_nm_process/7UatqvR9">average half-pitch of a memory cell manufactured circa 2018</a></li> <li>10 nm – thickness of <a href="/facts/Cell_wall/DYXJVrnw">cell wall</a> in <a href="/facts/Gram_staining/E20u5av2">Gram</a>-negative <a href="/facts/Bacteria/wC8xSCsU">bacteria</a></li></ul> <h2 id="10-nanometers">10 nanometers</h2> <p>To help compare different <a href="/facts/Order_of_magnitude/cWzRP2dM">orders of magnitude</a> this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> between 10−8 and 10−7 <a href="/facts/Metre/hPhzc1CV">m</a> (10 nm and 100 nm). </p> <ul><li>10 nm Shortest <a href="/facts/Extreme_ultraviolet/tRW9pqeI">extreme ultraviolet</a> wavelength or longest <a href="/facts/X-ray/wseP79cN">X-ray</a> wavelength<a class="footnote-ref" id="fnref:88" href="#fn:88"><sup>88</sup></a></li> <li>10 nm – the average length of a <a href="/facts/Nanowire/Ege0K9Ek">nanowire</a></li> <li>10 nm – lower size of tobacco smoke<a class="footnote-ref" id="fnref:89" href="#fn:89"><sup>89</sup></a></li> <li>10 nm – the <a href="/facts/10_nm_process/h5qaJnz9">average half-pitch of a memory cell manufactured circa 2016</a> <a href="/facts/32_nm_process/CsdohJVh">–</a>2017</li> <li>13 nm – the length of the wavelength that is used for <a href="/facts/EUV_lithography/NHpdP37J">EUV lithography</a></li> <li>14 nm – length of a <a href="/facts/Porcine_circovirus/uqSMP4Ek">porcine circovirus</a></li> <li>14 nm – the <a href="/facts/14_nm_process/lQYsD92n">average half-pitch of a memory cell manufactured circa 2013</a></li> <li>15 nm – length of an antibody</li> <li>18 nm – diameter of <a href="/facts/Tobacco_mosaic_virus/36sVcLw2">tobacco mosaic virus</a><a class="footnote-ref" id="fnref:90" href="#fn:90"><sup>90</sup></a> (Generally, <a href="/facts/Virus_(biology)/mf88Bcbl">viruses</a> range in size from 20 nm to 450 nm.)</li> <li>20 nm – length of a <a href="/facts/Nanobe/DMsUXCeh">nanobe</a>, could be one of the smallest forms of life</li> <li>20–80 nm – thickness of <a href="/facts/Cell_wall/DYXJVrnw">cell wall</a> in <a href="/facts/Gram-positive_bacteria/H6WYQ17e">Gram-positive bacteria</a><a class="footnote-ref" id="fnref:91" href="#fn:91"><sup>91</sup></a></li> <li>20 nm – thickness of <a href="/facts/Bacteria/wC8xSCsU">bacterial</a> <a href="/facts/Flagellum/nvQRcbgJ">flagellum</a><a class="footnote-ref" id="fnref:92" href="#fn:92"><sup>92</sup></a></li> <li>22 nm – the <a href="/facts/22_nm_process/zr0VI9w6">average half-pitch of a memory cell manufactured circa 2011–2012</a></li> <li>22 nm – smallest feature size of production <a href="/facts/Microprocessor/Fx9CaQht">microprocessors</a> in September 2009<a class="footnote-ref" id="fnref:93" href="#fn:93"><sup>93</sup></a></li> <li>25 nm – diameter of a <a href="/facts/Microtubule/ENL1TxSe">microtubule</a></li> <li>30 nm – lower size of cooking oil smoke</li> <li>30.8568 nm – 1 yoctoparsec</li> <li>32 nm – the <a href="/facts/32_nm_process/CsdohJVh">average half-pitch of a memory cell manufactured circa 2009–2010</a></li> <li>40 nm – extreme <a href="/facts/Ultraviolet/kncBUqn5">ultraviolet</a> wavelength</li> <li>45 nm – the <a href="/facts/45_nm_process/hlbmxAme">average half-pitch of a memory cell manufactured circa 2007–2008</a></li> <li>50 nm – upper size for airborne <a href="/facts/Virus/mf88Bcbl">virus</a> particles</li> <li>50 nm – <a href="/facts/Flying_height/x2QWf5G7">flying height</a> of the <a href="/facts/Disk_read-and-write_head/WdpxUpjK">head</a> of a <a href="/facts/Hard_disk/kekLSGSE">hard disk</a><a class="footnote-ref" id="fnref:94" href="#fn:94"><sup>94</sup></a></li> <li>65 nm – the <a href="/facts/65_nm_process/yqoIVRgR">average half-pitch of a memory cell manufactured circa 2005–2006</a></li> <li>58 nm – height of a <a href="/facts/T7_bacteriophage/uWTvHxrJ">T7 bacteriophage</a></li> <li>90 nm – <a href="/facts/HIV/AIDS/RqLIEMuJ">human immunodeficiency virus (HIV)</a> (generally, <a href="/facts/Virus/mf88Bcbl">viruses</a> range in size from 20 nm to 450 nm)</li> <li>90 nm – the <a href="/facts/90_nm_process/mmjMro9E">average half-pitch of a memory cell manufactured circa 2002–2003</a></li> <li>100 nm – Length of a <a href="/facts/Mesoporous_silica/tVR2Q6aI">mesoporous silica</a> nanoparticle</li></ul> <h2 id="100-nanometers">100 nanometers</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> between 10−7 and 10−6 <a href="/facts/Metre/hPhzc1CV">m</a> (100 <a href="/facts/Nanometre/a98sjHyu">nm</a> and 1 <a href="/facts/Micrometre/7eDFxD2L">μm</a>). </p> <ul><li>100 nm – greatest particle size that can fit through a <a href="/facts/Surgical_mask/azNpaTV3">surgical mask</a><a class="footnote-ref" id="fnref:95" href="#fn:95"><sup>95</sup></a></li> <li>100 nm – 90% of particles in wood <a href="/facts/Smoke/KRJaumoC">smoke</a> are smaller than this.</li> <li>120 nm – greatest particle size that can fit through a <a href="/facts/ULPA/6r5vVJ3c">ULPA</a> filter<a class="footnote-ref" id="fnref:96" href="#fn:96"><sup>96</sup></a></li> <li>120 nm – diameter of a <a href="/facts/Human_immunodeficiency_virus/ulY2rgzu">human immunodeficiency virus</a> (HIV)<a class="footnote-ref" id="fnref:97" href="#fn:97"><sup>97</sup></a></li> <li>120 nm – approximate diameter of <a href="/facts/Severe_acute_respiratory_syndrome_coronavirus_2/DxF8rDc1">SARS-CoV-2</a><a class="footnote-ref" id="fnref:98" href="#fn:98"><sup>98</sup></a></li> <li>125 nm – standard depth of pits on <a href="/facts/Compact_disc/g51GRloc">compact discs</a> (width: 500 nm, length: 850 nm to 3.5 μm)</li> <li>180 nm – typical length of the <a href="/facts/Rabies/rPDyNHwL">rabies virus</a></li> <li>200 nm – typical size of a <i><a href="/facts/Mycoplasma/G1T7m3rv">Mycoplasma</a></i> bacterium, among the smallest bacteria</li> <li>300 nm – greatest particle size that can fit through a <a href="/facts/HEPA/RTWmW8aE">HEPA</a> (high efficiency particulate air) filter (N100 removes up to 99.97% at 300 nm, N95 removes up to 95% at 300 nm)<a class="footnote-ref" id="fnref:99" href="#fn:99"><sup>99</sup></a></li> <li>300–400 nm – near <a href="/facts/Ultraviolet/kncBUqn5">ultraviolet</a> wavelength</li> <li>400–420 nm – wavelength of <a href="/facts/Violet_(color)/zcNJGApt">violet</a> light (see <a href="/facts/Color/XDvW7ESP">Color</a> and <a href="/facts/Visible_spectrum/frPBh8o5">Visible spectrum</a>)</li> <li>420–440 nm – wavelength of <a href="/facts/Indigo/ICSGEsqH">indigo</a> light</li> <li>440–500 nm – wavelength of <a href="/facts/Blue/DHWb8MUa">blue</a> light</li> <li>500–520 nm – wavelength of <a href="/facts/Cyan/AXtegEzm">cyan</a> light</li> <li>520–565 nm – wavelength of <a href="/facts/Green/gFTac7St">green</a> light</li> <li>565–590 nm – wavelength of <a href="/facts/Yellow/KrLNgk4v">yellow</a> light</li> <li>590–625 nm – wavelength of <a href="/facts/Orange_(colour)/FNScAQvv">orange</a> light</li> <li>625–700 nm – wavelength of <a href="/facts/Red/gLnFAVx4">red</a> light</li> <li>700–1.4 μm – wavelength of <a href="/facts/Near-infrared/44XdJNcc">near-infrared</a> radiation</li></ul> <h2 id="1-micrometer-or-1-micron">1 micrometer (or 1 micron)</h2> <p>The <i><a href="/facts/Micrometre/7eDFxD2L">micrometre</a></i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>μm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 10−6 <a href="/facts/Metre/hPhzc1CV">metres</a> (1/1000000 m = 0.000001 m). To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists some items with lengths between 10−6 and 10−5 m (between 1 and 10 <a href="/facts/Micrometre/7eDFxD2L">micrometers</a>, or μm). </p> <ul><li>~0.7–300 μm – wavelength of <a href="/facts/Infrared_radiation/44XdJNcc">infrared radiation</a></li> <li>1 μm – the side of a <a href="/facts/Square_(geometry)/JHJeMvmL">square</a> of area <a href="/facts/Orders_of_magnitude_(area)/fLnM7db9">10−12 m2</a></li> <li>1 μm – edge of <a href="/facts/Cube_(geometry)/65lUaAqN">cube</a> of volume <a href="/facts/Orders_of_magnitude_(volume)/tICdS8xu">10−18 m3</a> (1 fL)</li> <li>1–10 μm – diameter of a typical <a href="/facts/Bacterium/wC8xSCsU">bacterium</a></li> <li>1 μm – length of a <a href="/facts/Lysosome/0mcrzJU9">lysosome</a></li> <li>1–2 μm – <a href="/facts/Anthrax_disease/svk0t5G4">anthrax</a> spore<a class="footnote-ref" id="fnref:100" href="#fn:100"><sup>100</sup></a></li> <li>2 μm – length of an average <a href="/facts/E._coli/nR4Gvl56">E. coli</a> bacteria</li> <li>3–4 μm – size of a typical <a href="/facts/Yeast/eGD24nfI">yeast</a> cell<a class="footnote-ref" id="fnref:101" href="#fn:101"><sup>101</sup></a></li> <li>5 μm – length of a typical human <a href="/facts/Spermatozoon/sTG4GWc0">spermatozoon</a>'s head<a class="footnote-ref" id="fnref:102" href="#fn:102"><sup>102</sup></a></li> <li>6 μm – thickness of the tape in a 120-minute (C120) <a href="/facts/Compact_cassette/w8I5uyfs">compact cassette</a><a class="footnote-ref" id="fnref:103" href="#fn:103"><sup>103</sup></a></li> <li>7 μm – diameter of the <a href="/facts/Cell_nucleus/D7sFRa3c">nucleus</a> of a typical eukaryotic <a href="/facts/Cell_(biology)/bLM9UQvy">cell</a></li> <li>about 7 μm – diameter of human <a href="/facts/Red_blood_cell/Kggpq8Jh">red blood cells</a><a class="footnote-ref" id="fnref:104" href="#fn:104"><sup>104</sup></a></li> <li>3–8 μm – width of strand of <a href="/facts/Spider_silk/e1BwKC9S">spider web silk</a><a class="footnote-ref" id="fnref:105" href="#fn:105"><sup>105</sup></a></li> <li>5–10 μm – width of a <a href="/facts/Chloroplast/fo8U3yTx">chloroplast</a><a class="footnote-ref" id="fnref:106" href="#fn:106"><sup>106</sup></a></li> <li>8–11 μm – size of a ground-level fog or mist droplet<a class="footnote-ref" id="fnref:107" href="#fn:107"><sup>107</sup></a><a class="footnote-ref" id="fnref:108" href="#fn:108"><sup>108</sup></a></li> <li>7–12 μm – the diameter of human <a href="/facts/White_blood_cell/vsDunUK0">white blood cells</a></li> <li>8–10 μm – the diameter of human <a href="/facts/Macrophage/z7hkQu3o">macrophages</a></li></ul> <h2 id="10-micrometers">10 micrometers</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> between 10−5 <a href="/facts/Metre/hPhzc1CV">m</a> and 10−4 m (10 <a href="/facts/Micrometre/7eDFxD2L">μm</a> and 100 μm). </p> <ul><li>10 μm – width of <a href="/facts/Cotton/efXRcjbn">cotton</a> fibre<a class="footnote-ref" id="fnref:109" href="#fn:109"><sup>109</sup></a></li> <li>10 μm – <a href="/facts/Engineering_tolerance/zRrj34dF">tolerance</a> of a <a href="/facts/Lego/NW95SLjY">Lego</a> brick<a class="footnote-ref" id="fnref:110" href="#fn:110"><sup>110</sup></a></li> <li>10 μm – <a href="/facts/Transistor/Bmr8zwL0">transistor</a> width of the <a href="/facts/Intel_4004/kAoetjSU">Intel 4004</a>, the world's first commercial <a href="/facts/Microprocessor/Fx9CaQht">microprocessor</a></li> <li>10 μm – mean longest dimension of a human <a href="/facts/Red_blood_cell/Kggpq8Jh">red blood cell</a></li> <li>5–20 μm – <a href="/facts/Dust_mite/CwyrgWSA">dust mite</a> excreta<a class="footnote-ref" id="fnref:111" href="#fn:111"><sup>111</sup></a></li> <li>10.6 μm – wavelength of light emitted by a <a href="/facts/Carbon_dioxide_laser/RcnclQbA">carbon dioxide laser</a></li> <li>15 μm – width of <a href="/facts/Silk/XhxPpvvS">silk</a> fibre</li> <li>17 μm – minimum width of a strand of human hair<a class="footnote-ref" id="fnref:112" href="#fn:112"><sup>112</sup></a></li> <li>17.6 μm – one <a href="/facts/Twip/Dpy5SyHa">twip</a>, a unit of length in typography</li> <li>10 to 55 μm – width of <a href="/facts/Wool/AENKRTYl">wool</a> fibre<a class="footnote-ref" id="fnref:113" href="#fn:113"><sup>113</sup></a></li> <li>25.4 μm – 1/1,000 inch, commonly referred to as 1 <a href="/facts/Thou_(unit_of_length)/6jJ6uVUn">mil</a> in the U.S. and 1 <a href="/facts/Thou_(unit_of_length)/6jJ6uVUn">thou</a> in the UK</li> <li>30 μm – length of a human <a href="/facts/Skin_cell/4havlLzG">skin cell</a></li> <li>30.8568 μm – 1 zeptoparsec</li> <li>50 μm – typical length of <i><a href="/facts/Euglena_gracilis/eLABsMS9">Euglena gracilis</a></i>, a flagellate protist<a class="footnote-ref" id="fnref:114" href="#fn:114"><sup>114</sup></a></li> <li>50 μm – typical length of a human <a href="/facts/Liver/Rtp4Fk2b">liver</a> cell, an average-sized body cell</li> <li>50 μm – length of a <a href="/facts/Silt/HAxJkhDP">silt</a> particle</li> <li>60 μm – length of a <a href="/facts/Sperm_cell/RCxpXygQ">sperm cell</a></li> <li>78 μm — width of a pixel on the display of the iPhone 4, marketed as <a href="/facts/Retina_Display/J3zIpXba">Retina Display</a><a class="footnote-ref" id="fnref:115" href="#fn:115"><sup>115</sup></a></li> <li>70 to 180 μm – thickness of paper</li></ul> <h2 id="100-micrometers">100 micrometers</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> between 10−4 <a href="/facts/Metre/hPhzc1CV">m</a> and 10−3 m (100 <a href="/facts/Micrometre/7eDFxD2L">μm</a> and 1 <a href="/facts/Millimetre/25mdTXpa">mm</a>). The term <i>myriometer</i> (abbr. mom, equivalent to 100 micrometers; frequently confused with the <i>myriameter</i>, 10 kilometers)<a class="footnote-ref" id="fnref:116" href="#fn:116"><sup>116</sup></a> is deprecated; the decimal metric prefix <a href="/facts/Myria-/bcCPuemz">myrio-</a><a class="footnote-ref" id="fnref:117" href="#fn:117"><sup>117</sup></a> is obsolete<a class="footnote-ref" id="fnref:118" href="#fn:118"><sup>118</sup></a><a class="footnote-ref" id="fnref:119" href="#fn:119"><sup>119</sup></a><a class="footnote-ref" id="fnref:120" href="#fn:120"><sup>120</sup></a> and was not included among the <a href="/facts/SI_prefixes/Y2MzkaeL">prefixes</a> when the <a href="/facts/International_System_of_Units/S7YLglNz">International System of Units</a> was introduced in 1960. </p> <ul><li>100 μm – 1/10 of a millimeter</li> <li>100 μm – 0.00394 inches</li> <li>100 μm – smallest distance that can be seen with the <a href="/facts/Naked_eye/ePEIa0lK">naked eye</a></li> <li>100 μm – average diameter of a strand of <a href="/facts/Human_hair/L7vt9FL3">human hair</a><a class="footnote-ref" id="fnref:121" href="#fn:121"><sup>121</sup></a></li> <li>100 μm – thickness of a coat of <a href="/facts/Paint/Q176AsIG">paint</a></li> <li>100 μm – length of a <a href="/facts/Dust/vaNKP8wk">dust</a> particle</li> <li>120 μm – the <a href="/facts/Geometric_mean/6Nf6uk1A">geometric mean</a> of the <a href="/facts/Planck_length/4o04JYdD">Planck length</a> and the diameter of the <a href="/facts/Observable_universe/CdTGMdsp">observable universe</a>: √8.8 × 1026 m × 1.6 × 10−35 m</li> <li>120 μm – diameter of a <a href="/facts/Human/rlcTENsr">human</a> <a href="/facts/Ovum/gJyW3W3W">ovum</a></li> <li>170 μm – length of the largest mammalian <a href="/facts/Sperm_cell/RCxpXygQ">sperm cell</a> (rat)<a class="footnote-ref" id="fnref:122" href="#fn:122"><sup>122</sup></a></li> <li>170 μm – length of the largest <a href="/facts/Sperm_cell/RCxpXygQ">sperm cell</a> in nature, belonging to the <i><a href="/facts/Drosophila_bifurca/2mFrVuwn">Drosophila bifurca</a></i> fruit fly<a class="footnote-ref" id="fnref:123" href="#fn:123"><sup>123</sup></a><a class="footnote-ref" id="fnref:124" href="#fn:124"><sup>124</sup></a></li> <li>181 μm – maximum width of a strand of human hair<a class="footnote-ref" id="fnref:125" href="#fn:125"><sup>125</sup></a></li> <li>100–400 μm – length of <a href="/facts/Demodex_mite/YYxA9dEV">Demodex mites</a> living in human <a href="/facts/Hair_follicle/SXsAKufM">hair follicles</a></li> <li>175–200 μm – typical thickness of a <a href="/facts/Solar_cell/3L814UCC">solar cell</a>.</li> <li>200 μm – typical length of <i><a href="/facts/Paramecium/s82lDhHe">Paramecium caudatum</a></i>, a ciliate protist</li> <li>200 μm – nominal width of the smallest commonly available mechanical pencil lead (0.2 mm)</li> <li>250–300 μm – length of a <a href="/facts/Dust_mite/CwyrgWSA">dust mite</a><a class="footnote-ref" id="fnref:126" href="#fn:126"><sup>126</sup></a></li> <li>340 μm – length of a <a href="/facts/Pixel/UzwBvXBV">pixel</a> on a 17-inch monitor with a resolution of 1024×768</li> <li>500 μm – typical length of <i><a href="/facts/Amoeba_proteus/VduN881d">Amoeba proteus</a></i>, an amoeboid protist</li> <li>500 μm – <a href="/facts/Microelectromechanical_systems/TkhEzDpm">MEMS</a> micro-engine<a class="footnote-ref" id="fnref:127" href="#fn:127"><sup>127</sup></a></li> <li>500 μm – average length of a grain of <a href="/facts/Sand/MdTIt0M8">sand</a></li> <li>500 μm – average length of a grain of <a href="/facts/Salt/SCplalQ3">salt</a></li> <li>500 μm – average length of a grain of <a href="/facts/Sugar/jb5KXRHT">sugar</a></li> <li>560 μm – thickness of the central area of a human <a href="/facts/Cornea/oKA6clQT">cornea</a><a class="footnote-ref" id="fnref:128" href="#fn:128"><sup>128</sup></a></li> <li>750 μm – diameter of a <a href="/facts/Thiomargarita_namibiensis/blkQKIYY">Thiomargarita namibiensis</a>, the largest bacteria known<a class="footnote-ref" id="fnref:129" href="#fn:129"><sup>129</sup></a></li> <li>760 μm – thickness of an <a href="/facts/ISO/IEC_7810/ntfDju79">identification card</a></li></ul> <h2 id="1-millimeter">1 millimeter</h2> <p class="note">"1mm" redirects here. For the Perfume song, see <a href="/facts/Level3_(Perfume_album)/eP5Ebkpm">Level3 (Perfume album)</a>. For the measure, see <a href="/facts/Millimetre/25mdTXpa">millimetre</a>.</p> <p>The <i><a href="/facts/Millimetre/25mdTXpa">millimetre</a></i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>mm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 10−3 <a href="/facts/Metre/hPhzc1CV">metres</a> (1/1000 m = 0.001 m). To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists lengths between 10−3 m and 10−2 m (1 mm and 1 cm). </p> <ul><li>1.0 mm – 1/1,000 of a meter</li> <li>1.0 mm – 0.03937 <a href="/facts/Inch/CocFfm8p">inches</a> or 5/127 (exactly)</li> <li>1.0 mm – side of a <a href="/facts/Square_(geometry)/JHJeMvmL">square</a> of area <a href="/facts/1_E-6_m%C2%B2/fLnM7db9">1 mm²</a></li> <li>1.0 mm – diameter of a pinhead</li> <li>1.5 mm – average length of a flea<a class="footnote-ref" id="fnref:130" href="#fn:130"><sup>130</sup></a></li> <li>2.54 mm – distance between pins on old <a href="/facts/Dual_in-line_package/Qgu6Jave">dual in-line package</a> (DIP) electronic components</li> <li>5 mm – length of an average red ant</li> <li>5 mm – diameter of an average grain of rice</li> <li><a href="/facts/5.56%C3%9745mm_NATO/eT9ENFzY">5.56×45mm NATO</a> – standard ammunition size</li> <li>6 mm – approximate width of a pencil</li> <li>7 mm – length of a <i><a href="/facts/Paedophryne_amauensis/8WhNq6h4">Paedophryne amauensis</a></i>, the smallest-known vertebrate<a class="footnote-ref" id="fnref:131" href="#fn:131"><sup>131</sup></a></li> <li>7.1 mm – length of a sunflower seed</li> <li><a href="/facts/7.62%C3%9751mm_NATO/BTNCkLw5">7.62×51mm NATO</a> – common military ammunition size<a class="footnote-ref" id="fnref:132" href="#fn:132"><sup>132</sup></a></li> <li>8 mm – width of old-format home movie film</li> <li>8 mm – length of a <i><a href="/facts/Paedocypris_progenetica/KdtkPxpy">Paedocypris progenetica</a></i>, the smallest-known fish<a class="footnote-ref" id="fnref:133" href="#fn:133"><sup>133</sup></a></li></ul> <h2 id="1-centimeter">1 centimeter</h2> <p class="note">"10 mm" redirects here. For firearms cartridges, see <a href="/facts/10_mm_calibre/lDRNMAjh">10 mm calibre</a>.</p> <p>The <i><a href="/facts/Centimetre/urPkBdGR">centimetre</a></i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>cm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 10−2 <a href="/facts/Metre/hPhzc1CV">metres</a> (1/100 m = 0.01 m). To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists lengths between 10−2 m and 10−1 m (1 cm and 1 dm). </p> <ul><li>1 cm – 10 <a href="/facts/Millimetres/25mdTXpa">millimeters</a></li> <li>1 cm – 0.39 <a href="/facts/Inch/CocFfm8p">inches</a></li> <li>1 cm – edge of a <a href="/facts/Square/JHJeMvmL">square</a> of area <a href="/facts/Orders_of_magnitude_(area)/fLnM7db9">1 cm2</a></li> <li>1 cm – edge of a <a href="/facts/Cube_(geometry)/65lUaAqN">cube</a> of volume <a href="/facts/Orders_of_magnitude_(volume)/tICdS8xu">1 mL</a></li> <li>1 cm – length of a coffee bean</li> <li>1 cm – approximate width of average fingernail</li> <li>1.2 cm – length of a bee</li> <li>1.2 cm – diameter of a die</li> <li>1.5 cm – length of a very large mosquito</li> <li>1.6 cm – length of a Jaragua Sphaero, a very small reptile</li> <li>1.7 cm – length of a Thorius arboreus, the smallest salamander<a class="footnote-ref" id="fnref:134" href="#fn:134"><sup>134</sup></a></li> <li>2 cm – approximate width of an adult human finger</li> <li>2.54 cm – 1 inch</li> <li>3.08568 cm – 1 <a href="/facts/Attoparsec/57ANtRko">attoparsec</a></li> <li>3.4 cm – length of a quail egg<a class="footnote-ref" id="fnref:135" href="#fn:135"><sup>135</sup></a></li> <li>3.5 cm – width of film commonly used in motion pictures and still photography</li> <li>3.78 cm – amount of distance the Moon moves away from Earth each year<a class="footnote-ref" id="fnref:136" href="#fn:136"><sup>136</sup></a></li> <li>4.3 cm – minimum diameter of a golf ball<a class="footnote-ref" id="fnref:137" href="#fn:137"><sup>137</sup></a></li> <li>5 cm – usual diameter of a chicken egg</li> <li>5 cm – height of a hummingbird, the smallest-known bird</li> <li>5.08 cm – 2 <a href="/facts/Inch/CocFfm8p">inches</a>,</li> <li>5.5 × 5.5 × 5.5 cm – dimensions of a 3x3x3 Rubik's cube</li> <li>6.1 cm – average height of an apple</li> <li>7.3–7.5 cm – diameter of a baseball<a class="footnote-ref" id="fnref:138" href="#fn:138"><sup>138</sup></a></li> <li>8.6 cm × 5.4 cm – dimensions of a standard credit card (also called CR80)<a class="footnote-ref" id="fnref:139" href="#fn:139"><sup>139</sup></a><a class="footnote-ref" id="fnref:140" href="#fn:140"><sup>140</sup></a></li> <li>9 cm – length of a speckled padloper, the smallest-known turtle</li></ul> <h2 id="1-decimeter">1 decimeter</h2> <p class="note">"10cm" redirects here. For the band, see <a href="/facts/10cm_(band)/pBr70BGY">10cm (band)</a>.</p> <p>The <i><a href="/facts/Decimetre/Ww43QljM">decimetre</a></i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>dm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 10−1 <a href="/facts/Metre/hPhzc1CV">metres</a> (1/10 m = 0.1 m). To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists lengths between 10 <a href="/facts/Centimetre/urPkBdGR">centimeters</a> and 100 centimeters (10−1 meter and 1 meter). </p> <h3>Conversions</h3> <p>10 centimeters (abbreviated to 10 cm) is equal to: </p> <ul><li>1 <a href="/facts/Decimetre/Ww43QljM">decimeter</a> (dm), a term not in common use (1 <a href="/facts/Litre/QKwbQz8I">L</a> = 1 dm3.)</li> <li>100 <a href="/facts/Millimetre/25mdTXpa">millimeters</a></li> <li>3.9 <a href="/facts/Inch/CocFfm8p">inches</a></li> <li>a side of a <a href="/facts/Square_(geometry)/JHJeMvmL">square</a> of area <a href="/facts/Orders_of_magnitude_(area)/fLnM7db9">0.01 m2</a></li> <li>the edge of a <a href="/facts/Cube_(geometry)/65lUaAqN">cube</a> with a volume of <a href="/facts/Orders_of_magnitude_(one_cubic_millimetre_to_one_cubic_metre)/tICdS8xu">1×10−3 m3</a> (1 L)</li></ul> <h3>Wavelengths</h3> <ul><li>10 cm = 1.0 dm – wavelength of the highest <a href="/facts/Ultra_high_frequency/S6XDUaDY">UHF</a> radio frequency, <a href="/facts/Picosecond/62W8DK3Q">3 GHz</a></li> <li>12 cm = 1.2 dm – wavelength of the <a href="/facts/ISM_band/8r8D1WB7">2.45 GHz ISM radio band</a></li> <li>21 cm = 2.1 dm – wavelength of the <a href="/facts/21_cm_line/fQaWCT2t">1.4 GHz hydrogen emission line</a>, a <a href="/facts/Hyperfine_structure/aqj0dMut">hyperfine</a> transition of the hydrogen atom</li> <li>100 cm = 10 dm – wavelength of the lowest UHF radio frequency, <a href="/facts/Nanosecond/gARLTp4c">300 MHz</a></li></ul> <h3>Human-defined scales and structures</h3> <ul><li>10.16 cm = 1.016 dm – 1 <a href="/facts/Hand_(unit)/JPMvucm7">hand</a> used in measuring height of horses (4 inches)</li> <li>12 cm = 1.2 dm – diameter of a compact disc (CD) (= 120 mm)</li> <li>15 cm = 1.5 dm – length of a <a href="/facts/Bic_Cristal/cveAN5dQ">Bic pen</a> with cap on</li> <li>22 cm = 2.2 dm – diameter of a typical association football (soccer ball)</li> <li>30 cm = 3 dm – typical school-use ruler length (= 300 mm)</li> <li>30.48 cm = 3.048 dm – 1 <a href="/facts/Foot_(length)/XKamEGjV">foot</a> (measure)</li> <li>60 cm = 6 dm – standard depth (front to back) of a domestic kitchen worktop in Europe (= 600 mm)</li> <li>90 cm = 9 dm – average length of a rapier, a fencing sword<a class="footnote-ref" id="fnref:141" href="#fn:141"><sup>141</sup></a></li> <li>91.44 cm = 9.144 dm – one <a href="/facts/Yard/ddkwJz1q">yard</a> (measure)</li></ul> <h3>Nature</h3> <ul><li>10 cm = 1 dm – diameter of the human <a href="/facts/Cervix/qw3gl8Pq">cervix</a> upon entering the second stage of labour</li> <li>11 cm = 1.1 dm – length of an average potato in the US</li> <li>13 cm = 1.3 dm – body length of a <a href="/facts/Goliath_birdeater/kLXBRTY5">Goliath birdeater</a></li> <li>15 cm = 1.5 dm – approximate size of largest beetle species</li> <li>19 cm = 1.9 dm – length of a banana</li> <li>26.3 cm = 2.6 dm – length of average male human foot</li> <li>29.98 cm = 2.998 dm – distance light in vacuum travels in one <a href="/facts/Nanosecond/gARLTp4c">nanosecond</a></li> <li>30 cm = 3.0 dm – maximum leg length of a Goliath birdeater</li> <li>31 cm = 3.1 dm – wingspan of largest butterfly species <a href="/facts/Queen_Alexandra%27s_birdwing/bpdJoU6u"><i>Ornithoptera alexandrae</i></a></li> <li>32 cm – length of the <a href="/facts/Goliath_frog/K7PYKkRa">Goliath frog</a>, the world's largest frog</li> <li>46 cm = 4.6 dm – length of an average domestic cat</li> <li>50 to 65 cm = 5–6.5 dm – a coati's tail</li> <li>66 cm = 6.6 dm – length of the longest pine cones (produced by the sugar pine<a class="footnote-ref" id="fnref:142" href="#fn:142"><sup>142</sup></a>)</li></ul> <h3>Astronomical</h3> <ul><li>84 cm = 8.4 dm – approximate diameter of 2008 TS26, a meteoroid</li></ul> <h2 id="1-meter">1 meter</h2> <p class="note">"1m" redirects here. For other uses, see <a href="/facts/1M_(disambiguation)/HpaSCNlu">1M</a>.</p> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists lengths between one <a href="/facts/Metre/hPhzc1CV">meter</a> and ten meters. Light, in vacuum, travels 1 meter in 1⁄299,792,458, or 3.3356409519815E-9 of a second. </p> <h3>Conversions</h3> <p>1 <a href="/facts/Metre/hPhzc1CV">meter</a> is: </p> <ul><li>10 <a href="/facts/Decimetre/Ww43QljM">decimeters</a></li> <li>100 <a href="/facts/Centimetre/urPkBdGR">centimeters</a></li> <li>1,000 <a href="/facts/Millimetre/25mdTXpa">millimeters</a></li> <li>39.37 <a href="/facts/Inch/CocFfm8p">inches</a></li> <li>3.28 <a href="/facts/Foot_(length)/XKamEGjV">feet</a></li> <li>1.1 <a href="/facts/Yard/ddkwJz1q">yards</a></li> <li>side of <a href="/facts/Square_(geometry)/JHJeMvmL">square</a> with area <a href="/facts/1_E0_m%C2%B2/fLnM7db9">1 m2</a></li> <li>edge of <a href="/facts/Cube_(geometry)/65lUaAqN">cube</a> with surface area <a href="/facts/1_E0_m%C2%B2/fLnM7db9">6 m2</a> and volume <a href="/facts/1_E0_m%C2%B3/GPILKCtm">1 m3</a></li> <li>radius of <a href="/facts/Circle/9fy5ggKn">circle</a> with area <a href="/facts/1_E0_m%C2%B2/fLnM7db9">π m2</a></li> <li>radius of <a href="/facts/Sphere/jywYLNM2">sphere</a> with surface area <a href="/facts/1_E%2B1_m%C2%B2/fLnM7db9">4π m2</a> and volume <a href="/facts/1_E0_m%C2%B3/GPILKCtm">4/3π m3</a></li></ul> <h3>Human-defined scales and structures</h3> <ul><li>1 m – approximate height of the top part of a doorknob on a door</li> <li>1 m – diameter of a very large <a href="/facts/Beach_ball/MyPKRGHu">beach ball</a></li> <li>1.29 m – length of the <a href="/facts/Cross_Island_Chapel/0jsAcDXn">Cross Island Chapel</a>, the smallest church in the world</li> <li>1.4 m – length of a <a href="/facts/Peel_P50/NPmw7soI">Peel P50</a>, the world's smallest car</li> <li>1.435 m – standard gauge of railway track used by about 60% of railways in the world = 4 ft 81⁄2 in</li> <li>2.5 m – distance from the floor to the ceiling in an average residential house<a class="footnote-ref" id="fnref:143" href="#fn:143"><sup>143</sup></a></li> <li>2.7 m – length of the <a href="/facts/Starr_Bumble_Bee_II/XG3jy7qJ">Starr Bumble Bee II</a>, the smallest plane</li> <li>2.77–3.44 m – wavelength of the broadcast radio FM band 87–108 MHz</li> <li>3.05 m – the length of an old <a href="/facts/Mini/NRHuY0v3">Mini</a></li> <li>8 m – length of the <a href="/facts/Tsar_Bomba/qbjpPwN2">Tsar Bomba</a>, the largest bomb ever detonated</li> <li>8.38 m – the length of a London Bus (<a href="/facts/AEC_Routemaster/55eAQ7vQ">AEC Routemaster</a>)</li></ul> <h3>Sports</h3> <ul><li>2.44 m – height of an association football goal<a class="footnote-ref" id="fnref:144" href="#fn:144"><sup>144</sup></a></li> <li>2.45 m – highest high jump by a human (Javier Sotomayor)<a class="footnote-ref" id="fnref:145" href="#fn:145"><sup>145</sup></a></li> <li>3.05 m – (10 feet) height of the basket in basketball</li> <li>8.95 m – longest long jump by a human (Mike Powell)<a class="footnote-ref" id="fnref:146" href="#fn:146"><sup>146</sup></a></li></ul> <h3>Nature</h3> <ul><li>1 m – length of <i><a href="/facts/Rafflesia_arnoldii/CRUnLDeY">Rafflesia arnoldii</a></i>, the largest flower in the world</li> <li>1 m – height of <i><a href="/facts/Homo_floresiensis/N68vIkCG">Homo floresiensis</a></i> (the "Hobbit")</li> <li>1.15 m – a <a href="/facts/Pizote/d5LwE6Sy">pizote</a> (mammal)</li> <li>1.5 m – height of an <a href="/facts/Okapi/FIGeHfQj">okapi</a></li> <li>1.63 m – (5 feet 4 inches) (or 64 inches) – height of average U.S. female human as of 2002<a href="https://en.wikipedia.org/w/index.php?title=Orders_of_magnitude_(length)&action=edit">[update]</a> (source: U.S. Centers for Disease Control and Prevention (CDC))</li> <li>1.75 m – (5 feet 8 inches) – height of average U.S. male human as of 2002<a href="https://en.wikipedia.org/w/index.php?title=Orders_of_magnitude_(length)&action=edit">[update]</a> (source: U.S. CDC as per female above)</li> <li>2.4 m – wingspan of a <a href="/facts/Mute_swan/Vp78quHJ">mute swan</a></li> <li>2.5 m – height of a <a href="/facts/Sunflower/KIv0oR5w">sunflower</a></li> <li>2.7 m – length of a <a href="/facts/Leatherback_sea_turtle/Mg8e2UbB">leatherback sea turtle</a>, the largest living turtle</li> <li>2.72 m – (8 feet 11 inches) – tallest-known human (Robert Wadlow)<a class="footnote-ref" id="fnref:147" href="#fn:147"><sup>147</sup></a></li> <li>3 m – length of a <a href="/facts/Giant_Gippsland_earthworm/84Rmkaof">giant Gippsland earthworm</a></li> <li>3 m – length of an <a href="/facts/Komodo_dragon/GWInqcUn">Komodo dragon</a>, the largest living lizard</li> <li>3.63 m – the record wingspan for living birds (a <a href="/facts/Wandering_albatross/xcK0cNwk">wandering albatross</a>)</li> <li>3.7 m – leg span of a <a href="/facts/Japanese_spider_crab/gcaBczER">Japanese spider crab</a></li> <li>3.7 m – length of a <a href="/facts/Southern_elephant_seal/dehvKReX">southern elephant seal</a>, the largest living pinniped</li> <li>5 m – length of an <a href="/facts/Elephant/6prrEFFK">elephant</a></li> <li>5.2 m – height of a <a href="/facts/Giraffe/up0Jqouf">giraffe</a><a class="footnote-ref" id="fnref:148" href="#fn:148"><sup>148</sup></a></li> <li>5.5 m – height of a <i><a href="/facts/Baluchitherium/cPJRQhpn">Baluchitherium</a></i>, the largest land mammal ever lived</li> <li>6.5 m – wingspan of <i><a href="/facts/Argentavis/wblbebWI">Argentavis</a></i>, the largest flying bird known</li> <li>6.7 m – length of a <i><a href="/facts/Microchaetus_rappi/DDAXwKpe">Microchaetus rappi</a></i></li> <li>7.4 m – wingspan of <i><a href="/facts/Pelagornis/AJERacjK">Pelagornis</a>,</i> the bird with longest wingspan ever.<a class="footnote-ref" id="fnref:149" href="#fn:149"><sup>149</sup></a></li> <li>7.5 m – approximate length of the human gastrointestinal tract</li></ul> <h3>Astronomical</h3> <ul><li>3–6 m – approximate diameter of 2003 SQ222, a meteoroid</li> <li>4.1 m – diameter of <a href="/facts/2008_TC3/YqU8PSmj">2008 TC3</a>, a small asteroid that flew into the Earth's atmosphere on 7 October 2008<a class="footnote-ref" id="fnref:150" href="#fn:150"><sup>150</sup></a></li></ul> <h2 id="1-decameter">1 decameter</h2> <p>The <i><a href="/facts/Decametre/2A3vssMs">decametre</a></i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>dam</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 10 <a href="/facts/Metre/hPhzc1CV">meters</a> (101 m). To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists lengths between 10 and 100 meters. </p> <h3>Conversions</h3> <p>10 meters (very rarely termed a <a href="/facts/Decametre/2A3vssMs">decameter</a> which is abbreviated as dam) is equal to: </p> <ul><li>10 meters</li> <li>100 <a href="/facts/Decimetre/Ww43QljM">decimeters</a></li> <li>1,000 <a href="/facts/Centimetre/urPkBdGR">centimeters</a></li> <li>10,000 <a href="/facts/Millimetre/25mdTXpa">millimeters</a></li> <li>10,000,000 <a href="/facts/Micrometre/7eDFxD2L">micrometers</a> (or rarely 10,000,000 microns)</li> <li>32.8 <a href="/facts/Foot_(length)/XKamEGjV">feet</a></li> <li>11 <a href="/facts/Yards/ddkwJz1q">yards</a></li> <li>side of a <a href="/facts/Square_(geometry)/JHJeMvmL">square</a> with area <a href="/facts/1_E%2B2_m%C2%B2/fLnM7db9">100 m²</a></li></ul> <h3>Human-defined scales and structures</h3> <ul><li>10 meters – wavelength of the highest shortwave radio frequency, <a href="/facts/1_E7_Hz/gARLTp4c">30</a> M<a href="/facts/Hertz/6Wshj5qm">Hz</a></li> <li>10.2 meters – length of the <a href="/facts/Panzer_VIII_Maus/KRLUakbe">Panzer VIII Maus</a>, the world's largest tank</li> <li>12 meters – height of the <a href="/facts/Newby-McMahon_Building/tn4n9I8p">Newby-McMahon Building</a>, the world's littlest skyscraper</li> <li>23 meters – height of <a href="/facts/Luxor_Obelisk/sVvHvDrY">Luxor Obelisk</a>, located in the Place de la Concorde, Paris, France</li> <li>25 meters – wavelength of the broadcast radio shortwave band at <a href="/facts/1_E7_Hz/gARLTp4c">12</a> MHz</li> <li>29 meters – height of the <a href="/facts/Savudrija_Lighthouse/8qXNQHfp">Savudrija Lighthouse</a></li> <li>30 meters – height of <a href="/facts/Christ_the_Redeemer_(statue)/jj1bkh1Q">Christ the Redeemer</a></li> <li>31 meters – wavelength of the broadcast radio shortwave band at 9.7 MHz</li> <li>32 meters – length of one <a href="/facts/Minute_and_second_of_arc/tybs6YGC">arcsecond</a> of <a href="/facts/Latitude/IBYqkjhU">latitude</a> on the surface of the <a href="/facts/Earth/HLLmDfj0">Earth</a></li> <li>33.3 meters – height of the <a href="/facts/De_Noord/fS9VcnG3">De Noord</a>, the tallest windmill in the world</li> <li>34 meters – height of the <a href="/facts/Split_Point_Lighthouse/GuAHaRHk">Split Point Lighthouse</a> in Aireys Inlet, Victoria, Australia</li> <li>40 meters – wingspan of the <a href="/facts/Mil_Mi-26/H4CmVsX5">Mil Mi-26</a>, the largest helicopter</li> <li>40 meters – average depth beneath the seabed of the <a href="/facts/Channel_tunnel/qTu1Un9Q">Channel tunnel</a></li> <li>49 meters – wavelength of the broadcast radio shortwave band at 6.1 MHz</li> <li>50 meters – length of a <a href="/facts/Road_train/J6bzk5Ib">road train</a></li> <li>50 meters – height of the <a href="/facts/Arc_de_Triomphe/3TGr2JRm">Arc de Triomphe</a></li> <li>55 meters – height of the <a href="/facts/Leaning_Tower_of_Pisa/9aGmbfzy">Leaning Tower of Pisa</a></li> <li>62 meters – wingspan of <a href="/facts/Concorde/TAMElD6g">Concorde</a></li> <li>62.5 meters – height of <a href="/facts/Pyramid_of_Djoser/Qu8yXfQf">Pyramid of Djoser</a></li> <li>64 meters – wingspan of a <a href="/facts/Boeing_747-400/T1o6m6d5">Boeing 747-400</a></li> <li>69 meters – wingspan of an <a href="/facts/Antonov_An-124_Ruslan/TcEvHRQP">Antonov An-124 Ruslan</a></li> <li>70 meters – length of the <a href="/facts/Bayeux_Tapestry/MucPRuFc">Bayeux Tapestry</a></li> <li>70 meters – width of a typical <a href="/facts/Association_football_field/PST7Hk7R">association football field</a></li> <li>73 meters – wingspan of a <a href="/facts/Airbus_A380/cVuVbEsf">Airbus A380</a></li> <li>73 meters – height of the <a href="/facts/Taj_Mahal/fNCuLPX7">Taj Mahal</a></li> <li>77 meters – wingspan of a <a href="/facts/Boeing_747-8/HoywfG8f">Boeing 747-8</a></li> <li>88.4 meters – wingspan of an <a href="/facts/Antonov_An-225_Mriya/J3znmW7G">Antonov An-225 Mriya</a> transport aircraft</li> <li>93 meters – height of the <a href="/facts/Statue_of_Liberty/TlymQ7JI">Statue of Liberty</a> (<i>Liberty Enlightening the World</i>)</li> <li>96 meters – height of <a href="/facts/Big_Ben/fB5vSpbe">Big Ben</a></li> <li>100 meters – wavelength of the lowest shortwave radio frequency, <a href="/facts/1_E6_Hz/gARLTp4c">3</a> MHz</li></ul> <h3>Sports</h3> <ul><li>11 meters – approximate width of a doubles tennis court</li> <li>15 meters – width of a standard FIBA basketball court</li> <li>15.24 meters – width of an NBA basketball court (50 feet)</li> <li>18.44 meters – distance between the front of the pitcher's rubber and the rear point of home plate on a baseball field (60 feet, 6 inches)<a class="footnote-ref" id="fnref:151" href="#fn:151"><sup>151</sup></a></li> <li>20 meters – length of cricket pitch (22 yards)<a class="footnote-ref" id="fnref:152" href="#fn:152"><sup>152</sup></a></li> <li>27.43 meters – distance between bases on a baseball field (90 feet)</li> <li>28 meters – length of a standard FIBA basketball court</li> <li>28.65 meters – length of an NBA basketball court (94 feet)</li> <li>49 meters – width of an American football field (531⁄3 yards)</li> <li>59.436 meters – width of a Canadian football field (65 yards)</li> <li>70 meters – typical width of an association football field</li> <li>91 meters – length of an American football field (100 yards, measured between the goal lines)</li></ul> <h3>Nature</h3> <ul><li>10 meters – average length of human digestive tract</li> <li>12 meters – height of a <a href="/facts/Saguaro_cactus/d8CmXlzl">saguaro cactus</a></li> <li>12 meters – length of a <a href="/facts/Whale_shark/JNKjpvJf">whale shark</a>, largest living fish</li> <li>12 meters – wingspan of a <i><a href="/facts/Quetzalcoatlus/yAR0rDWM">Quetzalcoatlus</a></i>, a pterosaur</li> <li>12.8 meters – length of a <i><a href="/facts/Titanoboa/IcQva8es">Titanoboa</a></i>, the largest snake to have ever lived</li> <li>13 meters – length of a <a href="/facts/Giant_squid/jNIw5vaP">giant squid</a> and <a href="/facts/Colossal_squid/RIRss7u1">colossal squid</a>, the largest living invertebrates</li> <li>15 meters – approximate distance the tropical circles of latitude are moving towards the equator and the polar circles are moving towards the poles each year due to a natural, gradual decrease in the Earth's axial tilt</li> <li>16 meters – length of a <a href="/facts/Sperm_whale/mBUge07C">sperm whale</a>, the largest toothed whale</li> <li>18 meters – height of a <i><a href="/facts/Sauroposeidon/dWYxjBbf">Sauroposeidon</a></i>, the tallest-known dinosaur</li> <li>20 meters – length of a <i><a href="/facts/Leedsichthys/uLmBFoeq">Leedsichthys</a></i>, the largest-known fish to have lived</li> <li>21 meters – height of <a href="/facts/High_Force/h22pexKA">High Force</a> waterfall in England</li> <li>30.5 meters – length of the <a href="/facts/Lion%27s_mane_jellyfish/MkA38Fb8">lion's mane jellyfish</a>, the largest jellyfish in the world</li> <li>33 meters – length of a <a href="/facts/Blue_whale/CSlRTeCf">blue whale</a>,<a class="footnote-ref" id="fnref:153" href="#fn:153"><sup>153</sup></a> the largest animal on earth, living or extinct, in terms of mass</li> <li>39 meters – length of a <i><a href="/facts/Supersaurus/0YL7lXtj">Supersaurus</a></i>, the longest-known dinosaur and longest vertebrate<a class="footnote-ref" id="fnref:154" href="#fn:154"><sup>154</sup></a></li> <li>52 meters – height of <a href="/facts/Niagara_Falls/xoxUleQq">Niagara Falls</a><a class="footnote-ref" id="fnref:155" href="#fn:155"><sup>155</sup></a></li> <li>55 meters – length of a <a href="/facts/Bootlace_worm/dpLLXakp">bootlace worm</a>, the longest-known animal<a class="footnote-ref" id="fnref:156" href="#fn:156"><sup>156</sup></a></li> <li>66 meters – highest possible sea level rise due to a complete melting of all ice on Earth</li> <li>83 meters – height of a <a href="/facts/Western_hemlock/9HvboqoG">western hemlock</a></li> <li>84 meters – height of <a href="/facts/General_Sherman_(tree)/I3w1wplT">General Sherman</a>, the largest tree in the world</li></ul> <h3>Astronomical</h3> <ul><li>30 meters – diameter of <a href="/facts/1998_KY26/awz2mo3c">1998 KY26</a>, a rapidly spinning meteoroid</li> <li>30.8568 meters – 1 femtoparsec</li> <li>32 meters – approximate diameter of <a href="/facts/2008_HJ/4GsR7Elk">2008 HJ</a>, a small meteoroid</li></ul> <h2 id="1-hectometer">1 hectometer</h2> <p>The <i><a href="/facts/Hectometre/y4vg9uCK">hectometre</a></i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>hm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 100 <a href="/facts/Metre/hPhzc1CV">meters</a> (102 m). To compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a> this section lists lengths between 100 meters and 1,000 meters (1 <a href="/facts/Kilometre/hdQp79QE">kilometer</a>). </p> <h3>Conversions</h3> <p>100 meters (sometimes termed a hectometer) is equal to: </p> <ul><li>328 <a href="/facts/Foot_(length)/XKamEGjV">feet</a></li> <li>one side of a <a href="/facts/1_E%2B4_m%C2%B2/DPz2HDGr">1 hectare</a> square</li> <li>a fifth of a modern <a href="/facts/Li_(Chinese_unit)/M327CsjN">li</a>, a Chinese unit of measurement</li> <li>the approximate distance travelled by light in 300 <a href="/facts/Nanosecond/gARLTp4c">nanoseconds</a></li></ul> <h3>Human-defined scales and structures</h3> <ul><li>100 meters – wavelength of the highest medium wave radio frequency, <a href="/facts/1_E6_Hz/gARLTp4c">3 MHz</a></li> <li>100 meters – spacing of location marker posts on British motorways</li> <li>110 meters – height of the <a href="/facts/Saturn_V/WhpUEFJM">Saturn V</a></li> <li>122 meters – height of the <a href="/facts/SpaceX_Starship/zkm1P9kA">Starship</a>, the tallest rocket currently under development by <a href="/facts/SpaceX/2tKHsVdJ">SpaceX</a></li> <li>138.8 meters – height of the <a href="/facts/Great_Pyramid_of_Giza/7p5HrMFb">Great Pyramid of Giza</a> (Pyramid of Cheops)</li> <li>139 meters – height of the world's tallest roller coaster, <a href="/facts/Kingda_Ka/3d2WwNAj">Kingda Ka</a><a class="footnote-ref" id="fnref:157" href="#fn:157"><sup>157</sup></a></li> <li>157 meters – height of the <a href="/facts/Cologne_Cathedral/uBjfSxgj">Cologne Cathedral</a></li> <li>162 meters – height of the <a href="/facts/Ulm_Minster/EVLwFq9a">Ulm Minster</a>, the tallest church building in the world</li> <li>165 meters – height of the <a href="/facts/Dushanbe_Flagpole/1KjDtVLm">Dushanbe Flagpole</a>, the tallest flagpole from May 2011 to September 2014</li> <li>169 meters – height of the <a href="/facts/Washington_Monument/3Ir2QT65">Washington Monument</a></li> <li>171 meters – height of the <a href="/facts/Jeddah_Flagpole/zv5ws54K">Jeddah Flagpole</a>, the tallest flagpole from September 2014 to December 2021</li> <li>182 meters – height of the <a href="/facts/Statue_of_Unity/p29KRQUt">Statue of Unity</a>, the world's tallest statue</li> <li>187 meters – shortest wavelength of the broadcast radio AM band, <a href="/facts/1_E6_Hz/gARLTp4c">1600 kHz</a></li> <li>192 meters – height of the <a href="/facts/Gateway_Arch/DaAHC0YW">Gateway Arch</a></li> <li>202 meters – height of the <a href="/facts/Cairo_Flagpole/9AQCy9Y2">Cairo Flagpole</a>, the tallest flagpole as of December 2021</li> <li>202 meters – length of the <a href="/facts/Sz%C3%A9chenyi_Chain_Bridge/hJfFWuaC">Széchenyi Chain Bridge</a> connecting Buda and Pest</li> <li>220 meters – height of the <a href="/facts/Hoover_Dam/WIPXAeBe">Hoover Dam</a></li> <li>245 meters – length of the <a href="/facts/LZ_129_Hindenburg/aqkMcIEh">LZ 129 Hindenburg</a></li> <li>270 meters – length of the <i><a href="/facts/Titanic/loD4esxz">Titanic</a></i></li> <li>318 meters – height of The <a href="/facts/New_York_Times_Building/lPWIoKmU">New York Times Building</a></li> <li>318.9 meters – height of the <a href="/facts/Chrysler_Building/AG45agPV">Chrysler Building</a></li> <li>328 meters – height of Auckland's <a href="/facts/Sky_Tower_(Auckland)/l4At877a">Sky Tower</a>, the tallest free-standing structure in the Southern Hemisphere (1996–2022)</li> <li>330 meters – height of the <a href="/facts/Eiffel_Tower/IptQeofK">Eiffel Tower</a> (including antenna)<a class="footnote-ref" id="fnref:158" href="#fn:158"><sup>158</sup></a></li> <li>336 meters – height of the world's tallest bridge as of October 2023, the <a href="/facts/Millau_Viaduct/5Ajkgy0S">Millau Viaduct</a></li> <li>364.75 meters – length of the <a href="/facts/Icon_of_the_Seas/TsoMWvFG">Icon of the Seas</a></li> <li>390 meters – height of the <a href="/facts/Empire_State_Building/GgehSMmV">Empire State Building</a></li> <li>400–800 meters – approximate heights of the world's tallest skyscrapers from 1931 to 2010</li> <li>458 meters – length of the <a href="/facts/Knock_Nevis/4IC8tSAz">Knock Nevis</a>, the world's largest supertanker</li> <li>553.33 meters – height of the <a href="/facts/CN_Tower/1rwRybLJ">CN Tower</a>,<a class="footnote-ref" id="fnref:159" href="#fn:159"><sup>159</sup></a> the tallest structure in North America</li> <li>555 meters – longest wavelength of the broadcast radio AM band, <a href="/facts/1_E5_Hz/zdW1DEb2">540 kHz</a></li> <li>630 meters – height of the <a href="/facts/KVLY-TV_mast/7G2nHb1y">KVLY-TV mast</a>, one of the tallest structures in the world</li> <li>646 meters – height of the <a href="/facts/Warsaw_radio_mast/geyf0Emg">Warsaw radio mast</a>, the world's tallest structure until its collapse in 1991</li> <li>679 meters – height of <a href="/facts/Merdeka_118/9lplXk5L">Merdeka 118</a>, the second tallest structure in <a href="/facts/Kuala_Lumpur/2dCzRWjL">Kuala Lumpur</a>, <a href="/facts/Malaysia/8zbUMzCP">Malaysia</a></li> <li>828 meters – height of <a href="/facts/Burj_Khalifa/YIwfnMf4">Burj Khalifa</a>, world's tallest structure since 17 January 2009<a class="footnote-ref" id="fnref:160" href="#fn:160"><sup>160</sup></a></li> <li>1,000 meters – wavelength of the lowest mediumwave radio frequency, <a href="/facts/1_E5_Hz/zdW1DEb2">300 kHz</a></li></ul> <h3>Sports</h3> <ul><li>100 meters – the distance a very fast human can run in about 10 seconds</li> <li>100.584 meters – length of a Canadian football field between the goal lines (110 <a href="/facts/Yard/ddkwJz1q">yards</a>)</li> <li>91.5 meters – 137 meters – length of a soccer field<a class="footnote-ref" id="fnref:161" href="#fn:161"><sup>161</sup></a></li> <li>105 meters – length of football pitch (UEFA stadium categories 3 and 4)</li> <li>105 meters – length of a typical football field</li> <li>109.73 meters – total length of an American football field (120 yards, including the end zones)</li> <li>110–150 meters – the width of an Australian football field</li> <li>135–185 meters – the length of an Australian football field</li> <li>137.16 meters – total length of a Canadian football field, including the end zones (150 yards)</li></ul> <h3>Nature</h3> <ul><li>115.5 meters – height of the world's tallest tree in 2007, the <a href="/facts/Hyperion_(tree)/PkWyBBUy">Hyperion</a> sequoia<a class="footnote-ref" id="fnref:162" href="#fn:162"><sup>162</sup></a></li> <li>310 meters – maximum depth of <a href="/facts/Lake_Geneva/PfT7sVga">Lake Geneva</a></li> <li>340 meters – distance sound travels in air at sea level in one second; see <a href="/facts/Speed_of_sound/dYtbt1nf">Speed of sound</a></li> <li>947 meters – height of the <a href="/facts/Tugela_Falls/Gx0AHo5B">Tugela Falls</a>, the highest waterfall in Africa</li> <li>979 meters – height of the <a href="/facts/Angel_Falls/77cutvDE">Angel Falls</a>, the world's highest free-falling waterfall (Venezuela)</li></ul> <h3>Astronomical</h3> <ul><li>270 meters – length of <a href="/facts/99942_Apophis/xEEpaxYe">99942 Apophis</a></li> <li>535 meters – length of <a href="/facts/25143_Itokawa/V57ybCSg">25143 Itokawa</a>,<a class="footnote-ref" id="fnref:163" href="#fn:163"><sup>163</sup></a> a small asteroid visited by a spacecraft</li></ul> <h2 id="1-kilometer">1 kilometer</h2> <p>The <i><a href="/facts/Kilometre/hdQp79QE">kilometre</a></i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>km</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 1000 <a href="/facts/Metre/hPhzc1CV">meters</a> (103 m). To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> between 1 kilometer and 10 <a href="/facts/Kilometre/hdQp79QE">kilometers</a> (103 and 104 <a href="/facts/Metre/hPhzc1CV">meters</a>). </p> <h3>Conversions</h3> <p>1 <a href="/facts/Kilometre/hdQp79QE">kilometer</a> (unit symbol km) is equal to: </p> <ul><li>1,000 <a href="/facts/Metre/hPhzc1CV">meters</a></li> <li>0.621371 <a href="/facts/Mile/e22bY569">miles</a></li> <li>1,093.61 <a href="/facts/Yard/ddkwJz1q">yards</a></li> <li>3,280.84 <a href="/facts/Foot_(length)/XKamEGjV">feet</a></li> <li>39,370.1 <a href="/facts/Inch/CocFfm8p">inches</a></li> <li>100,000 <a href="/facts/Centimetre/urPkBdGR">centimeters</a></li> <li>1,000,000 <a href="/facts/Millimetre/25mdTXpa">millimeters</a></li> <li>Side of a <a href="/facts/Square_(geometry)/JHJeMvmL">square</a> of area <a href="/facts/1_E%2B6_m%C2%B2/fLnM7db9">1</a> <a href="/facts/Km%C2%B2/GgoBy690">km2</a></li> <li>Radius of a <a href="/facts/Circle/9fy5ggKn">circle</a> of area <a href="/facts/Pi/vC0UBj1q">π</a> km2</li></ul> <h3>Human-defined scales and structures</h3> <ul><li>1 km – wavelength of the highest <a href="/facts/Long_wave/w4flmdvu">long wave</a> radio frequency, <a href="/facts/1_E5_Hz/zdW1DEb2">300</a> <a href="/facts/KHz/6Wshj5qm">kHz</a><a class="footnote-ref" id="fnref:164" href="#fn:164"><sup>164</sup></a></li> <li>1.008 km – proposed height of the <a href="/facts/Jeddah_Tower/pb0plfMp">Jeddah Tower</a>, a <a href="/facts/Megatall_skyscraper/5nM0naVB">megatall skyscraper</a> under construction in <a href="/facts/Saudi_Arabia/uyUpe1J2">Saudi Arabia</a></li> <li>1.280 km – span of the <a href="/facts/Golden_Gate_Bridge/vGk0GVg1">Golden Gate Bridge</a> (distance between towers)<a class="footnote-ref" id="fnref:165" href="#fn:165"><sup>165</sup></a></li> <li>1.609 km – 1 statute mile</li> <li>1.852 km – 1 <a href="/facts/Nautical_mile/V4yJzvKw">nautical mile</a>, equal to 1 <a href="/facts/Arcminute/tybs6YGC">arcminute</a> of <a href="/facts/Latitude/IBYqkjhU">latitude</a> at the surface of the Earth<a class="footnote-ref" id="fnref:166" href="#fn:166"><sup>166</sup></a></li> <li>1.991 km – span of the <a href="/facts/Akashi_Kaiky%C5%8D_Bridge/BxzFlyrB">Akashi Kaikyō Bridge</a><a class="footnote-ref" id="fnref:167" href="#fn:167"><sup>167</sup></a></li> <li>2.309 km – axial length of the <a href="/facts/Three_Gorges_Dam/LMs99ndW">Three Gorges Dam</a>, the largest <a href="/facts/Dam/BroJFhEI">dam</a> in the world located in <a href="/facts/China/lTjIXY5p">China</a><a class="footnote-ref" id="fnref:168" href="#fn:168"><sup>168</sup></a></li> <li>3.991 km – length of the <a href="/facts/Akashi_Kaiky%C5%8D_Bridge/BxzFlyrB">Akashi Kaikyō Bridge</a>, longest <a href="/facts/Suspension_bridge/FoDavMf8">suspension bridge</a> in the world as of December 2008<a href="https://en.wikipedia.org/w/index.php?title=Orders_of_magnitude_(length)&action=edit">[update]</a><a class="footnote-ref" id="fnref:169" href="#fn:169"><sup>169</sup></a></li> <li>4 km – width of <a href="/facts/Central_Park/QgR0k7Hl">Central Park</a></li> <li>5.072 km – elevation of <a href="/facts/Tanggula_Mountain_Pass/lSbnHd0g">Tanggula Mountain Pass</a>, below highest peak in the <a href="/facts/Tanggula_Mountains/Ac6FRJlT">Tanggula Mountains</a>, highest <a href="/facts/Railway/9nJQbsDV">railway</a> pass in the world as of August 2005<a href="https://en.wikipedia.org/w/index.php?title=Orders_of_magnitude_(length)&action=edit">[update]</a><a class="footnote-ref" id="fnref:170" href="#fn:170"><sup>170</sup></a></li> <li>5.8 km – elevation of Cerro Aucanquilcha, highest road in the world, located in <a href="/facts/Chile/uEyTfEcx">Chile</a><a class="footnote-ref" id="fnref:171" href="#fn:171"><sup>171</sup></a></li> <li><a href="/facts/List_of_longest_runways/oMNComAD">98 airports</a> have paved runways from 4 km to 5.5 km in length.</li> <li>8 km – length of <a href="/facts/Palm_Jebel_Ali/ftYHzvn2">Palm Jebel Ali</a>, an <a href="/facts/Artificial_island/t4vHBFvY">artificial island</a> built off the coast of <a href="/facts/Dubai/v44jdkJK">Dubai</a></li> <li>9.8 km – length of <a href="/facts/The_World_(archipelago)/W2dhP21a">The World</a>, an artificial archipelago that is also built off the coast of <a href="/facts/Dubai/v44jdkJK">Dubai</a>, whose islands resemble a <a href="/facts/World_map/qbf0ucXf">world map</a></li></ul> <h3>Nature</h3> <ul><li>1.5 km – distance sound travels in water in one second</li></ul> <h3>Geographical</h3> <p class="note">See also: <a href="/facts/List_of_highest_mountains_on_Earth/uanjrrp1">List of highest mountains on Earth</a></p> <ul><li>1.637 km – deepest dive of <a href="/facts/Lake_Baikal/ndjtNeJ7">Lake Baikal</a> in <a href="/facts/Russia/jfkCwyxn">Russia</a>, the world's largest <a href="/facts/Freshwater/xMP2TxwI">freshwater</a> <a href="/facts/Lake/YP0xxn0E">lake</a><a class="footnote-ref" id="fnref:172" href="#fn:172"><sup>172</sup></a></li> <li>2.228 km – height of <a href="/facts/Mount_Kosciuszko/33bPvBCX">Mount Kosciuszko</a>, highest point on mainland <a href="/facts/Geography_of_Australia/TnAndY9X">Australia</a><a class="footnote-ref" id="fnref:173" href="#fn:173"><sup>173</sup></a></li> <li>Most of <a href="/facts/Manhattan/fF9JeXjh">Manhattan</a> is from 3 to 4 km wide.</li> <li>3.776 km – height of <a href="/facts/Mount_Fuji/DkJadl26">Mount Fuji</a>, highest peak in <a href="/facts/Japan/U5mz0SRT">Japan</a></li> <li>4.478 km – height of <a href="/facts/Matterhorn/uvGG8Mm4">Matterhorn</a></li> <li>4.509 km – height of <a href="/facts/Mount_Wilhelm/mJJ2mKvr">Mount Wilhelm</a>, highest peak in <a href="/facts/Papua_New_Guinea/RLaVlhFC">Papua New Guinea</a></li> <li>4.810 km – height of <a href="/facts/Mont_Blanc/Ds8dBfL2">Mont Blanc</a>, highest peak in the <a href="/facts/Alps/Q3zdQId4">Alps</a></li> <li>4.884 km – height of <a href="/facts/Carstensz_Pyramid/eEy6jgTq">Carstensz Pyramid</a>, highest peak in <a href="/facts/Oceania/vzTEvsfV">Oceania</a><a class="footnote-ref" id="fnref:174" href="#fn:174"><sup>174</sup></a></li> <li>4.892 km – height of <a href="/facts/Mount_Vinson/JXcADVPr">Mount Vinson</a>, highest peak in <a href="/facts/Antarctica/bEM5Lem5">Antarctica</a></li> <li>5.610 km – height of <a href="/facts/Mount_Damavand/k8EWbaQN">Mount Damavand</a>, highest peak in <a href="/facts/Iran/24yukge8">Iran</a></li> <li>5.642 km – height of <a href="/facts/Mount_Elbrus/nul1kWkB">Mount Elbrus</a>, highest peak in <a href="/facts/Europe/DTAtrKfh">Europe</a></li> <li>5.895 km – height of <a href="/facts/Mount_Kilimanjaro/82wb2Xy0">Mount Kilimanjaro</a>, highest peak in <a href="/facts/Africa/XkqQUP9s">Africa</a></li> <li>6.081 km – height of <a href="/facts/Mount_Logan/994SzJC0">Mount Logan</a>, highest peak in <a href="/facts/Canada/cWWFM8oc">Canada</a></li> <li>6.190 km – height of <a href="/facts/Denali/ud7RMYwY">Denali</a>, highest peak in <a href="/facts/North_America/djNjCQIl">North America</a></li> <li>6.959 km – height of <a href="/facts/Aconcagua/bsl5YnW8">Aconcagua</a>, highest peak in <a href="/facts/South_America/PhrFEMk7">South America</a></li> <li>7.5 km – depth of <a href="/facts/Cayman_Trench/LauPf0ra">Cayman Trench</a>, deepest point in the <a href="/facts/Caribbean_Sea/RPnJgdse">Caribbean Sea</a></li> <li>8.611 km – height of <a href="/facts/K2/7zeyrQ0s">K2</a>, second highest peak on <a href="/facts/Earth/HLLmDfj0">Earth</a></li> <li>8.848 km – height of <a href="/facts/Mount_Everest/hspjxkgv">Mount Everest</a>, highest peak on <a href="/facts/Earth/HLLmDfj0">Earth</a>, on the border between <a href="/facts/Nepal/yWCzTBR2">Nepal</a> and <a href="/facts/China/lTjIXY5p">China</a></li></ul> <h3>Astronomical</h3> <ul><li>1 km – diameter of <a href="/facts/1620_Geographos/9Y6b3yL0">1620 Geographos</a></li> <li>1 km – very approximate size of the smallest-known <a href="/facts/Moons_of_Jupiter/Rq3GMt28">moons of Jupiter</a></li> <li>1.4 km – diameter of <a href="/facts/Dactyl_(asteroid)/gqgaPb12">Dactyl</a>, the first confirmed <a href="/facts/Asteroid_moon/hIzB5S7X">asteroid moon</a></li> <li>4.8 km – diameter of <a href="/facts/5535_Annefrank/P8V5BcW2">5535 Annefrank</a>, an inner belt asteroid</li> <li>5 km – diameter of <a href="/facts/3753_Cruithne/ttB4J0UN">3753 Cruithne</a></li> <li>5 km – length of <a href="/facts/PSR_B1257%2B12/HzcsebRf">PSR B1257+12</a></li> <li>8 km – diameter of <a href="/facts/Themisto_(moon)/wjsxTK2D">Themisto</a>, one of <a href="/facts/Jupiter/95m7XjMT">Jupiter</a>'s moons</li> <li>8 km – diameter of the <a href="/facts/Vela_Pulsar/qMAAg0Et">Vela Pulsar</a></li> <li>8.6 km – diameter of <a href="/facts/Callirrhoe_(moon)/5tXaGnK7">Callirrhoe</a>, also known as Jupiter XVII</li> <li>9.737 km – length of <a href="/facts/PSR_B1919%2B21/ISjy6rQS">PSR B1919+21</a></li></ul> <h2 id="10-kilometers-1-myriameter">10 kilometers (1 myriameter)</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> between 10 and 100 <a href="/facts/Kilometre/hdQp79QE">kilometers</a> (104 to 105 <a href="/facts/Metre/hPhzc1CV">meters</a>). The <i>myriameter</i><a class="footnote-ref" id="fnref:175" href="#fn:175"><sup>175</sup></a> (sometimes also spelled <i>myriometer</i>; 10,000 meters) is a deprecated unit name; the decimal metric prefix <a href="/facts/Myria-/bcCPuemz">myria-</a><a class="footnote-ref" id="fnref:176" href="#fn:176"><sup>176</sup></a> (sometimes also written as <a href="/facts/Myrio-/bcCPuemz">myrio-</a><a class="footnote-ref" id="fnref:177" href="#fn:177"><sup>177</sup></a><a class="footnote-ref" id="fnref:178" href="#fn:178"><sup>178</sup></a><a class="footnote-ref" id="fnref:179" href="#fn:179"><sup>179</sup></a>) is obsolete<a class="footnote-ref" id="fnref:180" href="#fn:180"><sup>180</sup></a><a class="footnote-ref" id="fnref:181" href="#fn:181"><sup>181</sup></a><a class="footnote-ref" id="fnref:182" href="#fn:182"><sup>182</sup></a> and was not included among the <a href="/facts/SI_prefixes/Y2MzkaeL">prefixes</a> when the <a href="/facts/International_System_of_Units/S7YLglNz">International System of Units</a> was introduced in 1960. </p> <h3>Conversions</h3> <p>10 kilometers is equal to: </p> <ul><li>10,000 <a href="/facts/Metre/hPhzc1CV">meters</a></li> <li>About 6.2 <a href="/facts/Mile/e22bY569">miles</a></li> <li>1 <i>mil (the <a href="/facts/Scandinavian_mile/WKQxCJYc">Scandinavian mile</a>)</i>, now standardized as 10 km: <ul><li>1 mil, the unit of measure commonly used in <a href="/facts/Norway/wlDRKRTR">Norway</a> and <a href="/facts/Sweden/u3qC7lyj">Sweden</a><a class="footnote-ref" id="fnref:183" href="#fn:183"><sup>183</sup></a> used to be 11,295 m in Norway and 10,688 m in Sweden.</li></ul></li> <li><i><a href="/facts/Parasang/9bFcg1rh">farsang</a></i>, unit of measure commonly used in <a href="/facts/Iran/24yukge8">Iran</a> and <a href="/facts/Turkey/KIYAWAs0">Turkey</a><a class="footnote-ref" id="fnref:184" href="#fn:184"><sup>184</sup></a></li></ul> <h3>Sports</h3> <ul><li>42.195 km – length of the <a href="/facts/Marathon/IP3eBrhS">marathon</a><a class="footnote-ref" id="fnref:185" href="#fn:185"><sup>185</sup></a></li></ul> <h3>Human-defined scales and structures</h3> <ul><li>18 km – cruising altitude of <a href="/facts/Concorde/TAMElD6g">Concorde</a></li> <li>27 km – circumference of the <a href="/facts/Large_Hadron_Collider/XWJCFSqT">Large Hadron Collider</a>, as of May 2010<a href="https://en.wikipedia.org/w/index.php?title=Orders_of_magnitude_(length)&action=edit">[update]</a> the largest and highest energy <a href="/facts/Particle_accelerator/Pkuc08xC">particle accelerator</a></li> <li>34.668 km – highest manned <a href="/facts/Balloon/o9JQ2ykA">balloon</a> flight (Malcolm D. Ross and Victor E. Prather on 4 May 1961)<a class="footnote-ref" id="fnref:186" href="#fn:186"><sup>186</sup></a></li> <li>38.422 km – length of the Second <a href="/facts/Lake_Pontchartrain_Causeway/N3Se24TX">Lake Pontchartrain Causeway</a> in <a href="/facts/Louisiana/2GvfFcKE">Louisiana</a>, US</li> <li>39 km – undersea portion of the <a href="/facts/Channel_tunnel/qTu1Un9Q">Channel tunnel</a></li> <li>53.9 km – length of the <a href="/facts/Seikan_Tunnel/ycq93SK8">Seikan Tunnel</a>, as of October 2009<a href="https://en.wikipedia.org/w/index.php?title=Orders_of_magnitude_(length)&action=edit">[update]</a>, the longest rail tunnel in the world<a class="footnote-ref" id="fnref:187" href="#fn:187"><sup>187</sup></a></li> <li>77 km – rough total length of the <a href="/facts/Panama_Canal/Tau1ccDe">Panama Canal</a><a class="footnote-ref" id="fnref:188" href="#fn:188"><sup>188</sup></a></li></ul> <h3>Geographical</h3> <ul><li>10 km – height of <a href="/facts/Mauna_Kea/KJoe5ECR">Mauna Kea</a> in <a href="/facts/Hawaii/ImxFefeK">Hawaii</a>, measured from its base on the ocean floor</li> <li>11 km – deepest-known point of the ocean, <a href="/facts/Challenger_Deep/u70JRmWq">Challenger Deep</a> in the <a href="/facts/Mariana_Trench/FJB9X9nC">Mariana Trench</a></li> <li>11 km – average height of the <a href="/facts/Troposphere/JPDQq8cL">troposphere</a></li> <li>14 km – width of the <a href="/facts/Strait_of_Gibraltar/Bzko8DMw">Strait of Gibraltar</a></li> <li>21 km – length of <a href="/facts/Manhattan/fF9JeXjh">Manhattan</a></li> <li>22 km – narrowest width of the <a href="/facts/Cook_Strait/yaRkmoLI">Cook Strait</a> between New Zealand's main islands</li> <li>23 km – depth of the <a href="/facts/1931_Dogger_Bank_earthquake/YQuW9Wwo">largest earthquake ever recorded in the United Kingdom</a>, in 1931 at the <a href="/facts/Dogger_Bank/45hQxsnA">Dogger Bank</a> of the <a href="/facts/North_Sea/htGJNmsb">North Sea</a></li> <li>34 km – narrowest width of the <a href="/facts/English_Channel/UPjaSEXf">English Channel</a> at the <a href="/facts/Strait_of_Dover/SK5qvV1c">Strait of Dover</a></li> <li>50 km – approximate height of the <a href="/facts/Stratosphere/taBra67V">stratosphere</a></li> <li>90 km – width of the <a href="/facts/Bering_Strait/cnoNLuYE">Bering Strait</a></li></ul> <h3>Astronomical</h3> <ul><li>10 km – diameter of the most massive <a href="/facts/Neutron_star/4enfoxBA">neutron stars</a> (3–5 <a href="/facts/Solar_mass/j6Auhku8">solar masses</a>)</li> <li>13 km – mean diameter of <a href="/facts/Deimos_(moon)/Sm30nJWY">Deimos</a>, the smaller moon of <a href="/facts/Mars/AQGtVvz0">Mars</a></li> <li>20 km – diameter of the least massive neutron stars (1.44 solar masses)</li> <li>20 km – diameter of <a href="/facts/Leda_(moon)/oTyfPjwT">Leda</a>, one of <a href="/facts/Jupiter/95m7XjMT">Jupiter</a>'s moons</li> <li>20 km – diameter of <a href="/facts/Pan_(moon)/C2grsUxR">Pan</a>, one of <a href="/facts/Saturn/D54LcGJ9">Saturn</a>'s moons</li> <li>22 km – diameter of <a href="/facts/Phobos_(moon)/qqS9JvuG">Phobos</a>, the larger moon of <a href="/facts/Mars/AQGtVvz0">Mars</a></li> <li>27 km – height of <a href="/facts/Olympus_Mons/wnnlS99Q">Olympus Mons</a> above the <a href="/facts/Mars/AQGtVvz0">Mars</a> reference level,<a class="footnote-ref" id="fnref:189" href="#fn:189"><sup>189</sup></a><a class="footnote-ref" id="fnref:190" href="#fn:190"><sup>190</sup></a> the highest-known mountain of the <a href="/facts/Solar_System/QIcLSazQ">Solar System</a></li> <li>30.8568 km – 1 picoparsec</li> <li>43 km – diameter difference of <a href="/facts/Earth/HLLmDfj0">Earth</a>'s <a href="/facts/Equatorial_bulge/8CIPWl0I">equatorial bulge</a></li> <li>66 km – diameter of <a href="/facts/Naiad_(moon)/EDNFc3jy">Naiad</a>, the innermost of <a href="/facts/Neptune/1eucwHIC">Neptune</a>'s moons</li></ul> <h2 id="100-kilometers">100 kilometers</h2> <p>A length of <i>100 kilometers</i> (about 62 miles), as a rough amount, is relatively common in measurements on Earth and for some astronomical objects. It is the altitude at which the <a href="/facts/F%C3%A9d%C3%A9ration_A%C3%A9ronautique_Internationale/WoJkGK09">FAI</a> defines <a href="/facts/Spaceflight/zPrnATzo">spaceflight</a> to begin. </p><p>To help compare <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> between 100 and 1,000 <a href="/facts/Kilometre/hdQp79QE">kilometers</a> (105 and 106 <a href="/facts/Metre/hPhzc1CV">meters</a>). </p> <h3>Conversions</h3> <p>A distance of 100 kilometers is equal to about 62 miles (or 62.13711922 miles). </p> <h3>Human-defined scales and structures</h3> <ul><li>100 km – the <a href="/facts/Karman_line/CfvQ3fbp">Karman line</a>: the internationally recognized boundary of <a href="/facts/Outer_space/R3LRKyFs">outer space</a></li> <li>105 km – distance from <a href="/facts/Giridih/lck87wQK">Giridih</a> to <a href="/facts/Bokaro_Steel_City/wrI8PJPl">Bokaro</a></li> <li>109 km – length of <a href="/facts/High_Speed_1/yQyCy7QR">High Speed 1</a> between London and the Channel Tunnel<a class="footnote-ref" id="fnref:191" href="#fn:191"><sup>191</sup></a></li> <li>130 km – range of a <a href="/facts/Scud/Tch446nW">Scud</a>-A missile</li> <li>163 km – length of the <a href="/facts/Suez_Canal/1zYoNryp">Suez Canal</a></li> <li>164 km – length of the <a href="/facts/Danyang%E2%80%93Kunshan_Grand_Bridge/QhS0qeKc">Danyang–Kunshan Grand Bridge</a></li> <li>213 km – length of <a href="/facts/Paris_M%C3%A9tro/qUSSrUuN">Paris Métro</a></li> <li>217 km – length of the <a href="/facts/Grand_Union_Canal/UU1G6GDK">Grand Union Canal</a></li> <li>223 km – length of the <a href="/facts/Madrid_Metro/y6lh2jVh">Madrid Metro</a></li> <li>300 km – range of a Scud-B missile</li> <li>386 km – altitude of the <a href="/facts/International_Space_Station/VNPUBz9m">International Space Station</a></li> <li>408 km – length of the <a href="/facts/London_Underground/l3IPLz8F">London Underground</a> (active track)</li> <li>460 km – distance from <a href="/facts/London/KozCCsy9">London</a> to <a href="/facts/Paris/DrNHpwnA">Paris</a></li> <li>470 km – distance from <a href="/facts/Dublin/Fv8ezm8a">Dublin</a> to <a href="/facts/London/KozCCsy9">London</a> <a href="/facts/As_the_crow_flies/kt4Frbh5">as the crow flies</a></li> <li>600 km – range of a Scud-C missile</li> <li>600 km – height above ground of the <a href="/facts/Hubble_Space_Telescope/NQeIf0vw">Hubble Space Telescope</a></li> <li>804.67 km – (500 miles) distance of the <a href="/facts/Indy_500/zNasWCrK">Indy 500</a> automobile race</li></ul> <h3>Geographical</h3> <ul><li>42 km – width of <a href="/facts/Singapore/CQDkhUvD">Singapore</a></li> <li>75 km – width of <a href="/facts/Rhode_Island/WgrYmlzj">Rhode Island</a></li> <li>111 km – distance covered by one degree of <a href="/facts/Latitude/IBYqkjhU">latitude</a> on Earth's surface</li> <li>120 km – width of <a href="/facts/Brunei/dyz9JUn8">Brunei</a></li> <li>180 km – distance between <a href="/facts/Mumbai/BdoEc10R">Mumbai</a> and <a href="/facts/Nashik/H7LqSFvJ">Nashik</a></li> <li>200 km – width of <a href="/facts/Qatar/K4EkNXJE">Qatar</a></li> <li>203 km – length of <a href="/facts/Sognefjorden/cnus0gqj">Sognefjorden</a>, the third-largest <a href="/facts/Fjord/XbH8IzVE">fjord</a> in the world</li> <li>220 km – distance between <a href="/facts/Pune/MCeWSVBF">Pune</a> and Nashik</li> <li>240 km – width of <a href="/facts/Rwanda/UKR5UdKy">Rwanda</a></li> <li>240 km – widest width of the <a href="/facts/English_Channel/UPjaSEXf">English Channel</a></li> <li>400 km – width of <a href="/facts/West_Virginia/USP8LtCq">West Virginia</a></li> <li>430 km – length of the <a href="/facts/Pyrenees/YJ38kInj">Pyrenees</a></li> <li>450 km – length of the <a href="/facts/Grand_Canyon/5jdvIay7">Grand Canyon</a></li> <li>500 km – widest width of <a href="/facts/Geography_of_Sweden/Md3UMYSa">Sweden</a> from east to west</li> <li>501 km – width of <a href="/facts/Uganda/PabdegRm">Uganda</a></li> <li>550 km – distance from <a href="/facts/San_Francisco/cb9l7hbC">San Francisco</a> to <a href="/facts/Los_Angeles/pyXpYEX9">Los Angeles</a> <a href="/facts/As_the_crow_flies/kt4Frbh5">as the crow flies</a></li> <li>560 km – distance of <a href="/facts/Bordeaux%E2%80%93Paris/md9mT1jV">Bordeaux–Paris</a>, formerly[<i>when?</i>] the longest one-day professional cycling race<a class="footnote-ref" id="fnref:192" href="#fn:192"><sup>192</sup></a></li> <li>590 km – length of land boundary between <a href="/facts/Geography_of_Finland/ndsXx3AN">Finland</a> and <a href="/facts/Geography_of_Sweden/Md3UMYSa">Sweden</a></li> <li>724 km – length of the <a href="/facts/Om_River/yMb3Qz8F">Om River</a></li> <li>800 km – width of <a href="/facts/Germany/paluuWBX">Germany</a></li> <li>871 km – distance from <a href="/facts/Sydney/8TegRcwB">Sydney</a> to <a href="/facts/Melbourne/EHY9YxI0">Melbourne</a> (along the <a href="/facts/Hume_Highway/RcT5EeCz">Hume Highway</a>)</li> <li>897 km – length of the <a href="/facts/River_Douro/rrKSfhbf">River Douro</a></li> <li>900 km – distance from <a href="/facts/Berlin/pMTIRNXK">Berlin</a> to <a href="/facts/Stockholm/sD74W4Pm">Stockholm</a></li> <li>956 km – distance from <a href="/facts/Washington,_D.C./enXPK156">Washington, D.C.</a>, to <a href="/facts/Chicago/yPMokrXH">Chicago</a>, Illinois, <a href="/facts/As_the_crow_flies/kt4Frbh5">as the crow flies</a></li> <li>970 km – distance from <a href="/facts/Land%27s_End_to_John_o%27_Groats/X13M6AuH">Land's End to John o' Groats</a> <a href="/facts/As_the_crow_flies/kt4Frbh5">as the crow flies</a></li></ul> <h3>Astronomical</h3> <ul><li>100 km – the altitude at which the <a href="/facts/F%C3%A9d%C3%A9ration_A%C3%A9ronautique_Internationale/WoJkGK09">FAI</a> defines <a href="/facts/Spaceflight/zPrnATzo">spaceflight</a> to begin</li> <li>167 km – diameter of <a href="/facts/Amalthea_(moon)/XaNHMQLD">Amalthea</a>, one of <a href="/facts/Jupiter/95m7XjMT">Jupiter</a>'s inner moons</li> <li>200 km – width of <a href="/facts/Valles_Marineris/Yn3xDfDl">Valles Marineris</a></li> <li>220 km – diameter of <a href="/facts/Phoebe_(moon)/rp3CfgLm">Phoebe</a>, the largest of <a href="/facts/Saturn/D54LcGJ9">Saturn</a>'s outer moons</li> <li>300 km – the approximate distance travelled by light in one <a href="/facts/Millisecond/xHCyv235">millisecond</a></li> <li>340 km – diameter of <a href="/facts/Nereid_(moon)/VE3NlcK2">Nereid</a>, the third-largest moon of <a href="/facts/Neptune/1eucwHIC">Neptune</a> which has a highly <a href="/facts/Elliptic_orbit/SfuXuATN">elliptical orbit</a></li> <li>350 km – lower bound of <a href="/facts/Low_Earth_orbit/rq1TwayJ">Low Earth orbit</a></li> <li>420 km – diameter of <a href="/facts/Proteus_(moon)/jxkma0k0">Proteus</a>, the second-largest moon of Neptune</li> <li>468 km – diameter of the <a href="/facts/Asteroid/g7Ulr1VB">asteroid</a> <a href="/facts/4_Vesta/xnQ8acw1">4 Vesta</a></li> <li>472 km – diameter of <a href="/facts/Miranda_(moon)/ILmQCtMM">Miranda</a>, one of <a href="/facts/Uranus/x7YwT1ar">Uranus</a>'s major moons</li> <li>974.6 km – greatest diameter of <a href="/facts/Ceres_(dwarf_planet)/yIVEMYtG">1 Ceres</a>,<a class="footnote-ref" id="fnref:193" href="#fn:193"><sup>193</sup></a> the largest Solar System <a href="/facts/Asteroid/g7Ulr1VB">asteroid</a><a class="footnote-ref" id="fnref:194" href="#fn:194"><sup>194</sup></a></li></ul> <h2 id="1-megameter">1 megameter</h2> <p>The <i>megametre</i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>Mm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 1000000 <a href="/facts/Metre/hPhzc1CV">meters</a> (106 m). To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> starting at 106 <a href="/facts/Metre/hPhzc1CV">m</a> (1 Mm or 1,000 <a href="/facts/Kilometre/hdQp79QE">km</a>). </p> <h3>Conversions</h3> <p>1 megameter is equal to: </p> <ul><li>1000 km</li> <li>1 E+6 m (one million meters)</li> <li>approximately 621.37 <a href="/facts/Mile/e22bY569">miles</a></li> <li>1 E+12 μm (one trillion micrometers)</li> <li>Side of <a href="/facts/Square_(geometry)/JHJeMvmL">square</a> with area 1,000,000 km2</li></ul> <h3>Human-defined scales and structures</h3> <ul><li>2.100 Mm – length of proposed <a href="/facts/Iran-Pakistan-India_gas_pipe/1nEQ3bry">Iran-Pakistan-India gas pipe</a></li> <li>2.100 Mm – distance from <a href="/facts/Casablanca/pKXG2Nmy">Casablanca</a> to <a href="/facts/Rome/bh1Ttx3T">Rome</a></li> <li>2.288 Mm – length of the official <a href="/facts/Alaska_Highway/lmAfy37f">Alaska Highway</a> when it was built in the 1940s<a class="footnote-ref" id="fnref:195" href="#fn:195"><sup>195</sup></a></li> <li>3.069 Mm – length of <a href="/facts/Interstate_95/bwx4AeAH">Interstate 95</a> (from <a href="/facts/Houlton,_Maine/CFn2EuEX">Houlton, Maine</a>, to <a href="/facts/Miami/L5FsgQcb">Miami</a>, Florida)</li> <li>3.846 Mm – length of <a href="/facts/U.S._Route_1/bLk8m7zK">U.S. Route 1</a> (from <a href="/facts/Fort_Kent,_Maine/41aGpgfx">Fort Kent, Maine</a>, to <a href="/facts/Key_West,_Florida/JvtQRdTn">Key West, Florida</a>)</li> <li>5.000 Mm – width of the <a href="/facts/United_States/P0sCdLe5">United States</a></li> <li>5.007 Mm – estimated length of <a href="/facts/Interstate_90/TmMhQhWc">Interstate 90</a> (Seattle, Washington, to Boston, Massachusetts)</li> <li>5.614 Mm – length of the Australian <a href="/facts/Dingo_Fence/RnESj4Ge">Dingo Fence</a><a class="footnote-ref" id="fnref:196" href="#fn:196"><sup>196</sup></a></li> <li>6.371 Mm – global-average <a href="/facts/Earth_radius/PVsf0g2I">Earth radius</a></li> <li>6.4 Mm – length of the <a href="/facts/Great_Wall_of_China/aXVq4FrH">Great Wall of China</a></li> <li>7.821 Mm – length of the <a href="/facts/Trans-Canada_Highway/gu9BR2C6">Trans-Canada Highway</a>, the world's longest national highway (from <a href="/facts/Victoria,_British_Columbia/5bKrLfN2">Victoria, British Columbia</a>, to <a href="/facts/St._John%27s,_Newfoundland/D7HoujDF">St. John's, Newfoundland</a>)</li> <li>8.836 Mm – road distance between <a href="/facts/Prudhoe_Bay/bsstdeps">Prudhoe Bay</a>, Alaska, and <a href="/facts/Key_West,_Florida/JvtQRdTn">Key West, Florida</a>, the endpoints of the U.S. road network</li> <li>8.852 Mm – aggregate length of the <a href="/facts/Great_Wall_of_China/aXVq4FrH">Great Wall of China</a>, including trenches, hills and rivers<a class="footnote-ref" id="fnref:197" href="#fn:197"><sup>197</sup></a></li> <li>9.259 Mm – length of the <a href="/facts/Trans-Siberian_railway/nKn6Md9B">Trans-Siberian railway</a><a class="footnote-ref" id="fnref:198" href="#fn:198"><sup>198</sup></a></li></ul> <h3>Sports</h3> <ul><li>The <a href="/facts/Munda_Biddi_Trail/8UCwIKR9">Munda Biddi Trail</a> in <a href="/facts/Western_Australia/1ouCbwNh">Western Australia</a>, <a href="/facts/Australia/qLHpbppq">Australia</a>, is over 1,000 km long – the world's longest off-road cycle trail</li> <li>1.200 Mm – the length of the <a href="/facts/Paris%E2%80%93Brest%E2%80%93Paris/CdjCvnma">Paris–Brest–Paris</a> bicycling event</li> <li>Several endurance auto races are, or were, run for 1,000 km: <ul><li><a href="/facts/Bathurst_1000/I0Rzw0F5">Bathurst 1000</a></li> <li><a href="/facts/1000_km_Brands_Hatch/Hcy3phdM">1000 km Brands Hatch</a></li> <li><a href="/facts/1000_km_Buenos_Aires/I1WbBqVS">1000 km Buenos Aires</a></li> <li><a href="/facts/1000_km_Donington/YS1SgG4C">1000 km Donington</a></li> <li><a href="/facts/1000_km_Monza/dm9uV9Lx">1000 km Monza</a></li> <li><a href="/facts/1000_km_N%C3%BCrburgring/N0XTb9S9">1000 km Nürburgring</a></li> <li><a href="/facts/1000_km_Silverstone/rrhQu6Wg">1000 km Silverstone</a></li> <li><a href="/facts/1000_km_Spa/vbAP27qL">1000 km Spa</a></li> <li><a href="/facts/1000_km_Suzuka/P8jE0VFl">1000 km Suzuka</a></li> <li><a href="/facts/1000_km_Zeltweg/rPklhHRY">1000 km Zeltweg</a></li></ul></li></ul> <h3>Geographical</h3> <ul><li>1.010 Mm – distance from <a href="/facts/San_Diego/YFUP7gB9">San Diego</a> to <a href="/facts/El_Paso/SanXJ0WE">El Paso</a> <a href="/facts/As_the_crow_flies/kt4Frbh5">as the crow flies</a></li> <li>1.100 Mm – length of <a href="/facts/Italy/tUf0PDYF">Italy</a></li> <li>1.200 Mm – length of <a href="/facts/California/zLW2vdQJ">California</a></li> <li>1.200 Mm – width of <a href="/facts/Texas/B987WHF0">Texas</a></li> <li>1.500 Mm – length of the <a href="/facts/Gobi_Desert/Cgrf8RPQ">Gobi Desert</a></li> <li>1.600 Mm – length of the <a href="/facts/Namib/pVjUIn1F">Namib</a>, the oldest desert on Earth</li> <li>2.000 Mm – distance from <a href="/facts/Beijing/Bg4puFBv">Beijing</a> to <a href="/facts/Hong_Kong/4nAf3mqQ">Hong Kong</a> as the crow flies</li> <li>2.300 Mm – length of the <a href="/facts/Great_Barrier_Reef/3DkV4aad">Great Barrier Reef</a></li> <li>2.800 Mm – narrowest width of <a href="/facts/Atlantic_Ocean/EI4uChIb">Atlantic Ocean</a> (Brazil-West Africa)</li> <li>2.850 Mm – length of the <a href="/facts/Danube/8lMeM9xg">Danube</a> river</li> <li>2.205 Mm – length of <a href="/facts/Geography_of_Sweden/Md3UMYSa">Sweden</a>'s total land boundaries</li> <li>2.515 Mm – length of <a href="/facts/Geography_of_Norway/awmjGAmx">Norway</a>'s total land boundaries</li> <li>3.690 Mm – length of the <a href="/facts/Volga/B96tkIJj">Volga</a> river, longest in Europe</li> <li>4.000 Mm – length of the <a href="/facts/Kalahari_Desert/fEwF3sGL">Kalahari Desert</a></li> <li>4.350 Mm – length of the <a href="/facts/Yellow_River/LajkLtUU">Yellow River</a></li> <li>4.600 Mm – width of the <a href="/facts/Mediterranean_Sea/Vr2pzVbM">Mediterranean Sea</a></li> <li>4.800 Mm – length of the <a href="/facts/Sahara/JVlJd2VC">Sahara</a></li> <li>4.800 Mm – widest width of <a href="/facts/Atlantic_Ocean/EI4uChIb">Atlantic Ocean</a> (U.S.-Northern Africa)</li> <li>5.100 Mm – distance from <a href="/facts/Dublin/Fv8ezm8a">Dublin</a> to <a href="/facts/New_York_City/YlyvFmVC">New York</a> as the crow flies</li> <li>6.270 Mm – length of the <a href="/facts/Mississippi_River/RduarPzj">Mississippi</a>-<a href="/facts/Missouri_River/NL8Sj9Wb">Missouri River</a> system</li> <li>6.380 Mm – length of the <a href="/facts/Yangtze_River/f9A2h4rQ">Yangtze River</a></li> <li>6.400 Mm – Length of the <a href="/facts/Amazon_River/Ha9AzJY5">Amazon River</a></li> <li>6.758 Mm – Length of the <a href="/facts/Nile_River/vGoXVUFH">Nile</a> system, longest on <a href="/facts/Earth/HLLmDfj0">Earth</a></li> <li>8.200 Mm – Approximate Distance from <a href="/facts/Dublin/Fv8ezm8a">Dublin</a> to <a href="/facts/San_Francisco/cb9l7hbC">San Francisco</a></li></ul> <h3>Astronomical</h3> <ul><li>1.000 Mm – estimated shortest axis of <a href="/facts/Ellipsoid/pe9vm0Sh">triaxial</a> <a href="/facts/Dwarf_planet/IkQoCdwD">dwarf planet</a> <a href="/facts/Haumea/C1xJDm3B">Haumea</a></li> <li>1.186 Mm – diameter of <a href="/facts/Charon_(moon)/elazjsMp">Charon</a>, the largest moon of <a href="/facts/Pluto/egq7MBeR">Pluto</a></li> <li>1.280 Mm – diameter of the trans-Neptunian object <a href="/facts/50000_Quaoar/Yweth54G">50000 Quaoar</a></li> <li>1.436 Mm – diameter of <a href="/facts/Iapetus_(moon)/W9PCus81">Iapetus</a>, one of <a href="/facts/Saturn/D54LcGJ9">Saturn</a>'s major moons</li> <li>1.578 Mm – diameter of <a href="/facts/Titania_(moon)/Ts4j9JLM">Titania</a>, the largest of <a href="/facts/Uranus/x7YwT1ar">Uranus</a>'s moons</li> <li>1.960 Mm – estimated longest axis of <a href="/facts/Haumea_(dwarf_planet)/C1xJDm3B">Haumea</a></li> <li>2.326 Mm – diameter of the dwarf planet <a href="/facts/Eris_(dwarf_planet)/vuaR65F7">Eris</a>, the largest <a href="/facts/Trans-Neptunian_object/oF5vsbz9">trans-Neptunian object</a> found to date</li> <li>2.376 Mm – diameter of <a href="/facts/Pluto/egq7MBeR">Pluto</a></li> <li>2.707 Mm – diameter of <a href="/facts/Triton_(moon)/mxxRUygc">Triton</a>, largest moon of <a href="/facts/Neptune/1eucwHIC">Neptune</a></li> <li>3.122 Mm – diameter of <a href="/facts/Europa_(moon)/2A9nleK3">Europa</a>, the smallest <a href="/facts/Galilean_satellite/aN6tLUFc">Galilean satellite</a> of <a href="/facts/Jupiter/95m7XjMT">Jupiter</a></li> <li>3.476 Mm – diameter of <a href="/facts/Earth/HLLmDfj0">Earth</a>'s <a href="/facts/Moon/zKHqEMPb">Moon</a></li> <li>3.643 Mm – diameter of <a href="/facts/Io_(moon)/p3Uc8FmK">Io</a>, a moon of Jupiter</li> <li>4.821 Mm – diameter of <a href="/facts/Callisto_(moon)/et0eIutu">Callisto</a>, a moon of Jupiter</li> <li>4.879 Mm – diameter of <a href="/facts/Mercury_(planet)/lVa1GIyX">Mercury</a></li> <li>5.150 Mm – diameter of <a href="/facts/Titan_(moon)/lg0l9PCH">Titan</a>, the largest moon of Saturn</li> <li>5.262 Mm – diameter of Jupiter's moon <a href="/facts/Ganymede_(moon)/AmKsF10c">Ganymede</a>, the largest moon in the <a href="/facts/Solar_System/QIcLSazQ">Solar System</a></li> <li>6.371 Mm – <a href="/facts/Earth_radius/PVsf0g2I">radius of Earth</a></li> <li>6.792 Mm – diameter of <a href="/facts/Mars/AQGtVvz0">Mars</a></li></ul> <h2 id="10-megameters">10 megameters</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> starting at 107 <a href="/facts/Metre/hPhzc1CV">meters</a> (10 megameters or 10,000 <a href="/facts/Kilometre/hdQp79QE">kilometers</a>). </p> <h3>Conversions</h3> <p>10 megameters (10 Mm) is </p> <ul><li>6,215 <a href="/facts/Mile/e22bY569">miles</a></li> <li>side of a <a href="/facts/Square_(geometry)/JHJeMvmL">square</a> of area 100,000,000 <a href="/facts/Square_kilometre/GgoBy690">square kilometers</a> (km2)</li> <li>radius of a <a href="/facts/Circle/9fy5ggKn">circle</a> of area 314,159,265 km2</li></ul> <h3>Human-defined scales and structures</h3> <ul><li>11.085 Mm – length of the <a href="/facts/Kyiv/uVAMxK8R">Kyiv</a>-<a href="/facts/Vladivostok/NQQrTaMY">Vladivostok</a> railway, a longer variant of the <a href="/facts/Trans-Siberian_railway/nKn6Md9B">Trans-Siberian railway</a><a class="footnote-ref" id="fnref:199" href="#fn:199"><sup>199</sup></a></li> <li>13.300 Mm – length of roads rehabilitated and widened under the <a href="/facts/National_Highway_Development_Project/vxmQDH02">National Highway Development Project</a> (launched in 1998) in <a href="/facts/India/1kKHcnxM">India</a></li> <li>39.000 Mm – length of the <a href="/facts/SEA-ME-WE_3/rUTeKSHW">SEA-ME-WE 3</a> optical submarine telecommunications cable, joining 39 points between <a href="/facts/Norden,_Lower_Saxony/zt9pP9uq">Norden</a>, Germany, and <a href="/facts/Okinawa_Prefecture/2PNlxv5K">Okinawa</a>, Japan</li> <li>67.000 Mm – total length of <a href="/facts/National_highways_of_India/Uv3AzXxL">National Highways in India</a></li> <li>80.000 Mm – 20,000 (metric, French) <a href="/facts/League_(unit)/0E43AAtF">leagues</a> (see <a href="/facts/Jules_Verne/lLA0B0EF">Jules Verne</a>, <i><a href="/facts/Twenty_Thousand_Leagues_Under_the_Seas/Ihs0LVxM">Twenty Thousand Leagues Under the Seas</a></i>)</li></ul> <h3>Geographical</h3> <ul><li>10 Mm – approximate altitude of the outer boundary of the <a href="/facts/Exosphere/7vTtk7qC">exosphere</a></li> <li>10.001 Mm – length of the <a href="/facts/Meridian_arc/Ic30hDn1">meridian arc</a> from the <a href="/facts/North_Pole/gjfItQJH">North Pole</a> to the <a href="/facts/Equator/CjaxbVaN">Equator</a> (the original definition of the <a href="/facts/Metre/hPhzc1CV">meter</a> was based on this length)</li> <li>40.000 Mm – length of the <a href="/facts/Ring_of_Fire/UpRWnP2P">Ring of Fire</a></li> <li>60.000 Mm – total length of the <a href="/facts/Mid-ocean_ridge/wYdgdSW3">mid-ocean ridges</a></li></ul> <h3>Astronomical</h3> <ul><li>12.000 Mm – diameter of <a href="/facts/Sirius/sHCkClse">Sirius B</a>, a <a href="/facts/White_dwarf/gIYlTtrC">white dwarf</a><a class="footnote-ref" id="fnref:200" href="#fn:200"><sup>200</sup></a></li> <li>12.104 Mm – diameter of <a href="/facts/Venus/pADnueP6">Venus</a></li> <li>12.742 Mm – diameter of <a href="/facts/Earth/HLLmDfj0">Earth</a></li> <li>12.900 Mm – minimum distance of the <a href="/facts/Meteoroid/5PexF2mR">meteoroid</a> <a href="/facts/2004_FU162/QoLwBk6q">2004 FU162</a> from the centre of Earth on 31 March 2004, closest on record</li> <li>14.000 Mm – smallest diameter of Jupiter's <a href="/facts/Great_Red_Spot/8gbPpAJB">Great Red Spot</a></li> <li>19.000 Mm – separation between <a href="/facts/Pluto/egq7MBeR">Pluto</a> and <a href="/facts/Charon_(moon)/elazjsMp">Charon</a></li> <li>30.8568 Mm – 1 nanoparsec</li> <li>34.770 Mm – minimum distance of the <a href="/facts/Asteroid/g7Ulr1VB">asteroid</a> <a href="/facts/99942_Apophis/xEEpaxYe">99942 Apophis</a> on 13 April 2029 from the centre of Earth</li> <li>35.786 Mm – altitude of <a href="/facts/Geostationary_orbit/VBq1v5Kr">geostationary orbit</a></li> <li>40.005 Mm – polar circumference of the Earth</li> <li>40.077 Mm – equatorial circumference of the Earth</li> <li>49.528 Mm – diameter of <a href="/facts/Neptune/1eucwHIC">Neptune</a></li> <li>51.118 Mm – diameter of <a href="/facts/Uranus/x7YwT1ar">Uranus</a></li></ul> <h2 id="100-megameters">100 megameters</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Length/EwFyAqGH">lengths</a> starting at 108 <a href="/facts/Metre/hPhzc1CV">meters</a> (100 megameters or 100,000 <a href="/facts/Kilometre/hdQp79QE">kilometers</a> or 62,150 <a href="/facts/Mile/e22bY569">miles</a>). </p> <ul><li>102 Mm – diameter of <a href="/facts/HD_149026_b/gwTKFMMI">HD 149026 b</a>, an unusually dense <a href="/facts/Gas_giant/pmF6KztG">Jovian planet</a></li> <li>115 Mm – width of Saturn's Rings</li> <li>120 Mm – diameter of <a href="/facts/EBLM_J0555-57/5cLVXdFb">EBLM J0555-57</a>Ab, the smallest-known star</li> <li>120 Mm – diameter of <a href="/facts/Saturn/D54LcGJ9">Saturn</a></li> <li>142 Mm – diameter of <a href="/facts/Jupiter/95m7XjMT">Jupiter</a>, the largest planet in the <a href="/facts/Solar_System/QIcLSazQ">Solar System</a></li> <li>170 Mm – diameter of <a href="/facts/TRAPPIST-1/u5XTYQIw">TRAPPIST-1</a>, a star discovered to have seven planets around it</li> <li>174 Mm – diameter of <a href="/facts/OGLE-TR-122b/dRzDVDL9">OGLE-TR-122b</a>, one of the smallest known stars</li> <li>180 Mm – average distance covered during life</li> <li>215 Mm – diameter of <a href="/facts/Proxima_Centauri/6vSeytbA">Proxima Centauri</a>, the nearest star to the Solar System</li> <li>257 Mm – diameter of <a href="/facts/TrES-4b/YQvRgQs8">TrES-4</a>, one of the largest exoplanets</li> <li>260 Mm – diameter of the <a href="/facts/Barnard%27s_Star/9xrjwFXY">Barnard's Star</a></li> <li>272 Mm – diameter of <a href="/facts/WASP-12b/AbTSGaeE">WASP-12b</a></li> <li>299.792 Mm – one <a href="/facts/Light-second/0H0qncnG">light-second</a>; the distance <a href="/facts/Light/jeofpMn4">light</a> travels in <a href="/facts/Vacuum/BTk3goyV">vacuum</a> in one <a href="/facts/Second/jtFxnJXx">second</a> (see <a href="/facts/Speed_of_light/sKSQwdNx">speed of light</a>)</li> <li>314 Mm – diameter of <a href="/facts/CT_Cha_b/Huqc7bzd">CT Cha b</a></li> <li>384.4 Mm (238,855 mi) – average <a href="/facts/Lunar_distance_(astronomy)/8gWF1bT6">Earth–Moon distance</a><a class="footnote-ref" id="fnref:201" href="#fn:201"><sup>201</sup></a></li> <li>671 Mm – separation between <a href="/facts/Jupiter/95m7XjMT">Jupiter</a> and <a href="/facts/Europa_(moon)/2A9nleK3">Europa</a></li> <li>696 Mm – <a href="/facts/Solar_radius/5t1Xavju">radius</a> of <a href="/facts/Sun/CadPCVHh">Sun</a></li> <li>989 Mm – diameter of <a href="/facts/Epsilon_Indi/4Hjwnlh0">Epsilon Indi</a>, one of the nearest stars to Earth</li></ul> <h2 id="1-gigameter">1 gigameter</h2> <p>The <i>gigametre</i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>Gm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 1000000000 <a href="/facts/Metre/hPhzc1CV">meters</a> (109 m). To help compare different distances this section lists lengths starting at 109 <a href="/facts/Metre/hPhzc1CV">meters</a> (1 gigameter (Gm) or 1 billion <a href="/facts/Metre/hPhzc1CV">meters</a>). </p> <ul><li>1.2 Gm – separation between <a href="/facts/Saturn/D54LcGJ9">Saturn</a> and <a href="/facts/Titan_(moon)/lg0l9PCH">Titan</a></li> <li>1.39 Gm – diameter of <a href="/facts/Sun/CadPCVHh">Sun</a><a class="footnote-ref" id="fnref:202" href="#fn:202"><sup>202</sup></a><a class="footnote-ref" id="fnref:203" href="#fn:203"><sup>203</sup></a></li> <li>1.5 Gm – orbit from Earth of the <a href="/facts/James_Webb_Space_Telescope/w4GAWnWX">James Webb Space Telescope</a></li> <li>1.71 Gm – diameter of <a href="/facts/Alpha_Centauri/6BlySfIj">Alpha Centauri</a> A, one of the closest stars.<a class="footnote-ref" id="fnref:204" href="#fn:204"><sup>204</sup></a></li> <li>2.19 Gm – closest approach of <a href="/facts/Comet_Lexell/SlN2816u">Comet Lexell</a> to <a href="/facts/Earth/HLLmDfj0">Earth</a>, happened on 1 July 1770; closest <a href="/facts/Comet/w34utQCd">comet</a> approach on record</li> <li>2.38 Gm – diameter of <a href="/facts/Sirius/sHCkClse">Sirius</a> A, brightest naked eye star.<a class="footnote-ref" id="fnref:205" href="#fn:205"><sup>205</sup></a></li> <li>3 Gm – total length of "wiring" in the human brain<a class="footnote-ref" id="fnref:206" href="#fn:206"><sup>206</sup></a></li> <li>3.5 Gm – diameter of <a href="/facts/Vega/G3wJwhhl">Vega</a><a class="footnote-ref" id="fnref:207" href="#fn:207"><sup>207</sup></a></li> <li>4.2 Gm – diameter of <a href="/facts/Algol_B/mw03yQdn">Algol B</a></li> <li>4.3 Gm – circumference of <a href="/facts/Sun/CadPCVHh">Sun</a></li> <li>5.0 Gm – closest approach of <a href="/facts/Comet_Halley/DQongwTQ">Comet Halley</a> to Earth, happened on 10 April 837</li> <li>5.0 Gm – <i>(proposed) Size of the arms of the giant triangle shaped Michelson interferometer of the <a href="/facts/Laser_Interferometer_Space_Antenna/DAISKwem">Laser Interferometer Space Antenna</a> (LISA) planned to start observations sometime in the 2030s.</i></li> <li>7.9 Gm – diameter of <a href="/facts/Bellatrix/j3u5lwxK">Gamma Orionis</a>, a blue dwarf or blue giant</li> <li>9.0 Gm – estimated diameter of the <a href="/facts/Event_horizon/KXH2ptnI">event horizon</a> of <a href="/facts/Sagittarius_A*/5TWIRfgm">Sagittarius A*</a>, the <a href="/facts/Supermassive_black_hole/BcuTx8Q5">supermassive black hole</a> in the center of the <a href="/facts/Milky_Way/ulF6lccN">Milky Way</a> galaxy</li></ul> <h2 id="10-gigameters">10 gigameters</h2> <p>To help compare different <a href="/facts/Distance/hbXlaEFk">distances</a> this section lists lengths starting at 1010 <a href="/facts/Metre/hPhzc1CV">meters</a> (10 <a href="/facts/1_gigametre/YzL1bHGX">gigameters</a> (Gm) or 10 million <a href="/facts/Kilometre/hdQp79QE">kilometers</a>, or 0.07 <a href="/facts/Astronomical_unit/gjsbu5xU">astronomical units</a>). </p> <ul><li>10.4 Gm – diameter of Spica, an oval-shaped blue giant star and a <a href="/facts/List_of_supernova_candidates/Cg60K4v9">nearby supernova candidate</a>.<a class="footnote-ref" id="fnref:208" href="#fn:208"><sup>208</sup></a></li> <li>12.6 Gm – diameter of <a href="/facts/Pollux_(star)/Gv5T0K3a">Pollux</a>, the closest <a href="/facts/Red_giant/lla6Bsvy">red giant</a> <a href="/facts/Star/PFbd6ICx">star</a> to the Sun.<a class="footnote-ref" id="fnref:209" href="#fn:209"><sup>209</sup></a> It is a <a href="/facts/Red_clump/yMJP6v39">red clump</a> star fusing helium into carbon at its core.<a class="footnote-ref" id="fnref:210" href="#fn:210"><sup>210</sup></a></li> <li>15 Gm – closest distance of <a href="/facts/Comet_Hyakutake/QD4msVuP">Comet Hyakutake</a> from <a href="/facts/Earth/HLLmDfj0">Earth</a></li> <li>18 Gm – one <a href="/facts/Light-minute/0H0qncnG">light-minute</a> (see yellow sphere in right-hand diagram)</li> <li>24 Gm – radius of a <a href="/facts/Heliostationary_orbit/3HonupUd">heliostationary orbit</a></li> <li>30.8568 Gm – 1 microparsec</li> <li>35 Gm – approximate diameter of <a href="/facts/Arcturus/8W0qslPJ">Arcturus</a>, a close red giant star.<a class="footnote-ref" id="fnref:211" href="#fn:211"><sup>211</sup></a> It is on the <a href="/facts/Red_giant_branch/15Pg1F1F">red giant branch</a>, fusing hydrogen into helium in a shell surrounding an inert helium core.<a class="footnote-ref" id="fnref:212" href="#fn:212"><sup>212</sup></a></li> <li>46 Gm – <a href="/facts/Apsis/VaL6ow9w">perihelion</a> distance of <a href="/facts/Mercury_(planet)/lVa1GIyX">Mercury</a> (yellow ellipse on the right)</li> <li>55 Gm – 60,000-year <a href="/facts/Perigee/VaL6ow9w">perigee</a> of <a href="/facts/Mars/AQGtVvz0">Mars</a> (last achieved on 27 August 2003)</li> <li>58 Gm – average passing distance between <a href="/facts/Earth/HLLmDfj0">Earth</a> and Mars at the moment they overtake each other in their orbits</li> <li>61 Gm – diameter of <a href="/facts/Aldebaran/PPa2xB93">Aldebaran</a>, a red giant branch star (large star on right)<a class="footnote-ref" id="fnref:213" href="#fn:213"><sup>213</sup></a></li> <li>70 Gm – <a href="/facts/Apsis/VaL6ow9w">aphelion</a> distance of Mercury</li> <li>76 Gm – <a href="/facts/Neso_(moon)/b8KA9bXK">Neso</a>'s <a href="/facts/Apsis/VaL6ow9w">apocentric</a> distance; greatest distance of a <a href="/facts/Natural_satellite/AE4KQKbq">natural satellite</a> from its parent <a href="/facts/Planet/rbPjE6Bx">planet</a> (<a href="/facts/Neptune/1eucwHIC">Neptune</a>)</li></ul> <h2 id="100-gigameters">100 gigameters</h2> <p>To help compare distances at different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a> this section lists lengths starting at 1011 <a href="/facts/Metre/hPhzc1CV">meters</a> (100 gigameter or 100 million <a href="/facts/Kilometre/hdQp79QE">kilometers</a> or 0.7 <a href="/facts/Astronomical_unit/gjsbu5xU">astronomical units</a>). </p> <ul><li>103 Gm (0.69 au) – diameter of <a href="/facts/Rigel/WeeIXAAv">Rigel</a><a class="footnote-ref" id="fnref:214" href="#fn:214"><sup>214</sup></a></li> <li>109 Gm (0.7 au) – distance between Venus and the Sun</li> <li>149.6 Gm (93.0 million mi; 1.0 au) – average distance between the <a href="/facts/Earth/HLLmDfj0">Earth</a> and the Sun – the original definition of the <a href="/facts/Astronomical_unit/gjsbu5xU">astronomical unit</a></li> <li>199 Gm (1.3 au) – diameter of <a href="/facts/Rho_Persei/h1BAYIzL">Rho Persei</a>, an <a href="/facts/Asymptotic_giant_branch/R90sd1Hl">asymptotic giant branch</a> star, fusing carbon into neon in a shell surrounding an inert core.<a class="footnote-ref" id="fnref:215" href="#fn:215"><sup>215</sup></a></li> <li>228 Gm (1.5 au) – distance between <a href="/facts/Mars/AQGtVvz0">Mars</a> and the Sun</li> <li>248 Gm (1.7 au) – diameter of <a href="/facts/Enif/jo1a3BIl">Enif</a>, a small <a href="/facts/Red_supergiant/hPBWvABE">red supergiant</a> star in the constellation <a href="/facts/Pegasus_(constellation)/DpwfGQuF">Pegasus</a><a class="footnote-ref" id="fnref:216" href="#fn:216"><sup>216</sup></a></li> <li>280 Gm (1.9 au) – diameter of <a href="/facts/Deneb/L7dTfcog">Deneb</a>, a blue supergiant and the brightest star in the <a href="/facts/Cygnus_(constellation)/L1fYe414">Cygnus constellation</a><a class="footnote-ref" id="fnref:217" href="#fn:217"><sup>217</sup></a></li> <li>511 Gm (3.4 au) – average diameter of <a href="/facts/Mira/FtJV7za8">Mira</a>, a pulsating red giant and the progenitor of the <a href="/facts/Mira_variables/MnudJxL9">Mira variables</a>. It is an <a href="/facts/Asymptotic_giant_branch/R90sd1Hl">asymptotic giant branch</a> star.<a class="footnote-ref" id="fnref:218" href="#fn:218"><sup>218</sup></a></li> <li>570 Gm (3.8 au) – length of the tail of <a href="/facts/Comet_Hyakutake/QD4msVuP">Comet Hyakutake</a> measured by <i><a href="/facts/Ulysses_(spacecraft)/0nEMdFvj">Ulysses</a></i>; the actual value could be much higher</li> <li>590 Gm (3.9 au) – diameter of the <a href="/facts/Pistol_Star/7utF8pXU">Pistol Star</a>, a blue <a href="/facts/Hypergiant/Q95EmMhT">hypergiant</a> star<a class="footnote-ref" id="fnref:219" href="#fn:219"><sup>219</sup></a></li> <li>591 Gm (4.0 au) – minimum distance between the <a href="/facts/Earth/HLLmDfj0">Earth</a> and <a href="/facts/Jupiter/95m7XjMT">Jupiter</a></li> <li>780 Gm (5.2 au) – average distance between Jupiter and the Sun</li> <li>785 Gm (5.25 au) – diameter of <a href="/facts/Rho_Cassiopeiae/BEAdYRqe">Rho Cassiopeiae</a>, a rare <a href="/facts/Yellow_hypergiant/wguuSoKH">yellow hypergiant</a> star<a class="footnote-ref" id="fnref:220" href="#fn:220"><sup>220</sup></a></li> <li>947 Gm (6.4 au) – diameter of <a href="/facts/Antares/adRhtq7X">Antares A</a></li> <li>965 Gm (6.4 au) – maximum distance between the Earth and Jupiter</li></ul> <h2 id="1-terameter">1 terameter</h2> <p>The <i>terametre</i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>Tm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 1000000000000 <a href="/facts/Metre/hPhzc1CV">meters</a> (1012 m). To help compare different <a href="/facts/Distance/hbXlaEFk">distances</a>, this section lists lengths starting at 1012 <a href="/facts/Metre/hPhzc1CV">m</a> (1 Tm or 1 billion <a href="/facts/Kilometre/hdQp79QE">km</a> or 6.7 <a href="/facts/Astronomical_unit/gjsbu5xU">astronomical units</a>). </p> <ul><li>≈1 Tm – 6.7 au – diameter of the red supergiant <a href="/facts/Betelgeuse/BsD9Ap7C">Betelgeuse</a> based on multiple angular diameter estimates<a class="footnote-ref" id="fnref:221" href="#fn:221"><sup>221</sup></a></li> <li>1.032 Tm – 6.9 au – diameter of the blue hypergiant <a href="/facts/Eta_Carinae/zsrmE2Lo">Eta Carinae</a> (at optical depth 2/3)<a class="footnote-ref" id="fnref:222" href="#fn:222"><sup>222</sup></a></li> <li>1.079 Tm – 7.2 au – one <a href="/facts/Light-hour/0H0qncnG">light-hour</a></li> <li>1.114 Tm – 7.5 au – diameter of <a href="/facts/WOH_G64/1YrLUsoc">WOH G64</a>, a star in the <a href="/facts/Large_Magellanic_Cloud/7VYAehNa">Large Magellanic Cloud</a>, which recently transformed from a red hypergiant to a yellow hypergiant<a class="footnote-ref" id="fnref:223" href="#fn:223"><sup>223</sup></a></li> <li>1.4 Tm – 9.5 au – average distance between <a href="/facts/Saturn/D54LcGJ9">Saturn</a> and the <a href="/facts/Sun/CadPCVHh">Sun</a></li> <li>1.47 Tm – 9.9 au – diameter of <a href="/facts/HR_5171_A/MTe217o3">HR 5171 A</a>, a <a href="/facts/Yellow_hypergiant/wguuSoKH">yellow hypergiant</a> star.<a class="footnote-ref" id="fnref:224" href="#fn:224"><sup>224</sup></a></li> <li>1.5 Tm – 10 au – estimated diameter of <a href="/facts/VV_Cephei_A/4sNPMw9J">VV Cephei A</a>, a red hypergiant with a blue dwarf companion.<a class="footnote-ref" id="fnref:225" href="#fn:225"><sup>225</sup></a></li> <li>1.75 Tm – 11.7 au – estimated diameter of <a href="/facts/Mu_Cephei/CaQzAXAN">Mu Cephei</a>, a red supergiant (possibly hypergiant) among the <a href="/facts/List_of_largest_stars/XNsQIqwD">largest-known stars</a>.<a class="footnote-ref" id="fnref:226" href="#fn:226"><sup>226</sup></a></li> <li>2 Tm – 13.2 au – estimated diameter of <a href="/facts/VY_Canis_Majoris/pdF78cT2">VY Canis Majoris</a>, a red hypergiant that is among the <a href="/facts/List_of_largest_stars/XNsQIqwD">largest-known stars</a><a class="footnote-ref" id="fnref:227" href="#fn:227"><sup>227</sup></a><a class="footnote-ref" id="fnref:228" href="#fn:228"><sup>228</sup></a></li> <li>2.142 Tm – 14.3 au – estimated diameter of <a href="/facts/WOH_G64/1YrLUsoc">WOH G64</a>, prior to its transformation into a yellow hypergiant.</li> <li>2.9 Tm – 19.4 au – average distance between <a href="/facts/Uranus/x7YwT1ar">Uranus</a> and the Sun</li> <li>4.4 Tm – 29.4 au – <a href="/facts/Apsis/VaL6ow9w">perihelion</a> distance of <a href="/facts/Pluto/egq7MBeR">Pluto</a></li> <li>4.5 Tm – 30.1 au – average distance between <a href="/facts/Neptune/1eucwHIC">Neptune</a> and the Sun</li> <li>4.5 Tm – 30.1 au – inner radius of the <a href="/facts/Kuiper_belt/IvLzYp5P">Kuiper belt</a></li> <li>5.7 Tm – 38.1 au – perihelion distance of <a href="/facts/136199_Eris/vuaR65F7">Eris</a></li> <li>6.0 Tm – 40.5 au – distance from <a href="/facts/Earth/HLLmDfj0">Earth</a> at which the <a href="/facts/Pale_Blue_Dot/uVp0qBgq">Pale Blue Dot</a> photograph was taken.</li> <li>7.3 Tm – 48.8 au – <a href="/facts/Apsis/VaL6ow9w">aphelion</a> distance of <a href="/facts/Pluto/egq7MBeR">Pluto</a></li> <li>7.5 Tm – 50.1 au – outer boundary of the <a href="/facts/Kuiper_Belt/IvLzYp5P">Kuiper Belt</a></li></ul> <h2 id="10-terameters">10 terameters</h2> <p>To help compare different <a href="/facts/Distance/hbXlaEFk">distances</a> this section lists lengths starting at 1013 <a href="/facts/Metre/hPhzc1CV">m</a> (10 Tm or 10 billion <a href="/facts/Kilometre/hdQp79QE">km</a> or 67 <a href="/facts/Astronomical_unit/gjsbu5xU">astronomical units</a>). </p> <ul><li>10 Tm – 67 AU – diameter of a hypothetical <a href="/facts/Quasi-star/SmTEbbYy">quasi-star</a></li> <li>11.1 Tm – 74.2 AU – distance that <i><a href="/facts/Voyager_1/39jCxR9I">Voyager 1</a></i> began detecting returning particles from <a href="/facts/Termination_shock/Yc9ToWbA">termination shock</a></li> <li>11.4 Tm – 76.2 AU – <a href="/facts/Apsis/VaL6ow9w">perihelion</a> distance of <a href="/facts/90377_Sedna/6aXuaYoM">90377 Sedna</a></li> <li>12.1 Tm – 70 to 90 AU – distance to <a href="/facts/Termination_shock/Yc9ToWbA">termination shock</a> (<i>Voyager 1</i> crossed at 94 AU)</li> <li>12.9 Tm – 86.3 AU – distance to 90377 Sedna in March 2014</li> <li>13.2 Tm – 88.6 AU – distance to <i><a href="/facts/Pioneer_11/9QgrnSWp">Pioneer 11</a></i> in March 2014</li> <li>14.1 Tm – 94.3 AU – estimated radius of the <a href="/facts/Solar_System/QIcLSazQ">Solar System</a></li> <li>14.4 Tm – 96.4 AU – distance to <a href="/facts/136199_Eris/vuaR65F7">Eris</a> in March 2014 (now near its <a href="/facts/Apsis/VaL6ow9w">aphelion</a>)</li> <li>15.1 Tm – 101 AU – distance to <a href="/facts/Heliosphere/Yc9ToWbA">heliosheath</a></li> <li>16.5 Tm – 111 AU – distance to <i><a href="/facts/Pioneer_10/om14fT0h">Pioneer 10</a></i> as of March 2014</li> <li>16.6 Tm – 111.2 AU – distance to <i><a href="/facts/Voyager_2/9FAEaHUr">Voyager 2</a></i> as of May 2016</li> <li>18 Tm – 123.5 AU – distance between the <a href="/facts/Sun/CadPCVHh">Sun</a> to the farthest dwarf planet in the Solar System, the Farout <a href="/facts/2018_VG18/5mSNe05H">2018 VG18</a></li> <li>20.0 Tm – 135 AU – distance to <i><a href="/facts/Voyager_1/39jCxR9I">Voyager 1</a></i> as of May 2016</li> <li>20.6 Tm – 138 AU – distance to <i>Voyager 1</i> as of late February 2017</li> <li>21.1 Tm – 141 AU – distance to <i>Voyager 1</i> as of November 2017</li> <li>24.8 Tm – 166 AU – distance to <i>Voyager 1</i> as of November 2024</li> <li>25.9 Tm – 173 AU – one <a href="/facts/Light-day/0H0qncnG">light-day</a></li> <li>30.8568 Tm – 206.3 AU – 1 milliparsec</li> <li>55.7 Tm – 371 AU – aphelion distance of the <a href="/facts/Comet/w34utQCd">comet</a> <a href="/facts/Hale-Bopp/4BCn6rvu">Hale-Bopp</a></li></ul> <h2 id="100-terameters">100 terameters</h2> <p>To help compare different <a href="/facts/Distance/hbXlaEFk">distances</a> this section lists lengths starting at 1014 <a href="/facts/Metre/hPhzc1CV">m</a> (100 Tm or 100 billion <a href="/facts/Kilometre/hdQp79QE">km</a> or 670 <a href="/facts/Astronomical_unit/gjsbu5xU">astronomical units</a>). </p> <ul><li>140 Tm – 937 AU – <a href="/facts/Apsis/VaL6ow9w">aphelion</a> distance of <a href="/facts/90377_Sedna/6aXuaYoM">90377 Sedna</a></li> <li>172 Tm – 1150 AU – <a href="/facts/Schwarzschild_radius/jINV5oxD">Schwarzschild diameter</a> of <a href="/facts/H1821%2B643/Qffr8Uhn">H1821+643</a>, one of the most massive <a href="/facts/Black_hole/1r2lmkcF">black holes</a> known</li> <li>181 Tm – 1210 AU – one <a href="/facts/Light-week/0H0qncnG">light-week</a></li> <li>308.568 Tm – 2063 AU – 1 centiparsec</li> <li>757 Tm – 5059 AU – radius of the <a href="/facts/Stingray_Nebula/PHXWrEfo">Stingray Nebula</a><a class="footnote-ref" id="fnref:229" href="#fn:229"><sup>229</sup></a></li> <li>777 Tm – 5180 AU – one <a href="/facts/Light-month/IGc5NdQb">light-month</a></li></ul> <h2 id="1-petameter">1 petameter</h2> <p>The <i>petametre</i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>Pm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 1015 <a href="/facts/Metre/hPhzc1CV">meters</a>. To help compare different <a href="/facts/Distance/hbXlaEFk">distances</a> this section lists lengths starting at 1015 <a href="/facts/Metre/hPhzc1CV">m</a> (1 Pm or 1 trillion <a href="/facts/Kilometre/hdQp79QE">km</a> or 6685 <a href="/facts/Astronomical_unit/gjsbu5xU">astronomical units</a> (AU) or 0.11 <a href="/facts/Light-year/IGc5NdQb">light-years</a>). </p> <ul><li>1.0 Pm = 0.105702341 light-years</li> <li>1.9 Pm ± 0.5 Pm = 12,000 AU = 0.2 light-year radius of <a href="/facts/Cat%27s_Eye_Nebula/gvVk41YP">Cat's Eye Nebula</a>'s inner core<a class="footnote-ref" id="fnref:230" href="#fn:230"><sup>230</sup></a><a class="footnote-ref" id="fnref:231" href="#fn:231"><sup>231</sup></a></li> <li>3.08568 Pm = 20,626 AU = 1 deciparsec</li> <li>4.7 Pm = 30,000 AU = half-light-year diameter of <a href="/facts/Bok_globule/qjn2eW7e">Bok globule</a> <a href="/facts/Barnard_68/h2PBNYFK">Barnard 68</a><a class="footnote-ref" id="fnref:232" href="#fn:232"><sup>232</sup></a></li> <li>7.5 Pm – 50,000 AU – possible outer boundary of <a href="/facts/Oort_cloud/wdP3VNxd">Oort cloud</a> (other estimates are 75,000 to 125,000 or even 189,000 <a href="/facts/Astronomical_unit/gjsbu5xU">AU</a> (1.18, 2, and 3 <a href="/facts/Light-year/IGc5NdQb">light-years</a>, respectively))</li> <li>9.5 Pm – 63,241.1 AU – one <a href="/facts/Light-year/IGc5NdQb">light-year</a>, the distance light travels in one year</li> <li>9.9 Pm – 66,000 AU – <a href="/facts/Apsis/VaL6ow9w">aphelion</a> distance of the <a href="/facts/C/1999_F1_(Catalina)/snIMERBg">C/1999 F1 (Catalina)</a></li></ul> <h2 id="10-petameters">10 petameters</h2> <p>To help compare different distances this section lists lengths starting at 1016 <a href="/facts/Metre/hPhzc1CV">m</a> (10 Pm or 66,800 <a href="/facts/Astronomical_unit/gjsbu5xU">AU</a>, 1.06 <a href="/facts/Light-year/IGc5NdQb">light-years</a>). </p> <ul><li>15 Pm – 1.59 light-years – possible outer radius of <a href="/facts/Oort_cloud/wdP3VNxd">Oort cloud</a></li> <li>20 Pm – 2.11 light-years – maximum extent of influence of the Sun's <a href="/facts/Gravitational_field/K1uTmJFy">gravitational field</a></li> <li>30.9 Pm – 3.26 light-years – 1 <a href="/facts/Parsec/SwSsk57J">parsec</a></li> <li>39.9 Pm – 4.22 light-years – distance to <a href="/facts/Proxima_Centauri/6vSeytbA">Proxima Centauri</a> (nearest star to <a href="/facts/Sun/CadPCVHh">Sun</a>)</li> <li>81.3 Pm – 8.59 light-years – distance to <a href="/facts/Sirius/sHCkClse">Sirius</a></li> <li>94.6 Pm – 1 light-decade</li></ul> <h2 id="100-petameters">100 petameters</h2> <p>To help compare different <a href="/facts/Distance/hbXlaEFk">distances</a> this section lists lengths between 1017 <a href="/facts/Metre/hPhzc1CV">m</a> (100 Pm or 11 <a href="/facts/Light-year/IGc5NdQb">light-years</a>) and 1018 m (106 light-years). </p> <ul><li>110 Pm – 12 light-years – Distance to <a href="/facts/Tau_Ceti/1tzg8cmQ">Tau Ceti</a></li> <li>230 Pm – 24 light-years – Diameter of the <a href="/facts/Orion_Nebula/6VWbcqzL">Orion Nebula</a><a class="footnote-ref" id="fnref:233" href="#fn:233"><sup>233</sup></a><a class="footnote-ref" id="fnref:234" href="#fn:234"><sup>234</sup></a></li> <li>240 Pm – 25 light-years – Distance to <a href="/facts/Vega/G3wJwhhl">Vega</a></li> <li>260 Pm – 27 light-years – Distance to <a href="/facts/Beta_Canum_Venaticorum/hcwEWfWM">Chara</a>, a star approximately as bright as the Sun. Its faintness gives an idea how the <a href="/facts/Sun/CadPCVHh">Sun</a> would appear when viewed from this distance.</li> <li>308.568 Tm – 32.6 light-years – 1 dekaparsec</li> <li>350 Pm – 37 light-years – distance to <a href="/facts/Arcturus/8W0qslPJ">Arcturus</a></li> <li>373.1 Pm – 39.44 light-years – distance to <a href="/facts/TRAPPIST-1/u5XTYQIw">TRAPPIST-1</a>, a star recently discovered to have 7 planets around it</li> <li>400 Pm – 42 light-years – distance to <a href="/facts/Capella_(star)/bNQTaAjQ">Capella</a></li> <li>620 Pm – 65 light-years – distance to <a href="/facts/Aldebaran/PPa2xB93">Aldebaran</a></li> <li>750 Pm – 79.36 light-years – distance to <a href="/facts/Regulus/3Dw39x28">Regulus</a></li> <li>900 Pm – 92.73 light-years – distance to <a href="/facts/Algol/mw03yQdn">Algol</a></li> <li>946 Pm – 1 light-century</li></ul> <h2 id="1-exameter">1 exameter</h2> <p>The <i>exametre</i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>Em</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 1018 <a href="/facts/Metre/hPhzc1CV">meters</a>. To help compare different <a href="/facts/Distance/hbXlaEFk">distances</a> this section lists lengths between 1018 <a href="/facts/Metre/hPhzc1CV">m</a> (1 <a href="/facts/Exametre/YzL1bHGX">Em</a> or 105.7 <a href="/facts/Light-year/IGc5NdQb">light-years</a>) and 1019 m (10 Em or 1,057 light-years). </p> <ul><li>1.2 Em – 129 light-years – diameter of <a href="/facts/Messier_13/98BuIWhp">Messier 13</a> (a typical <a href="/facts/Globular_cluster/FL0EERJU">globular cluster</a>)</li> <li>1.6 Em – 172 ± 12.5 light-years – diameter of <a href="/facts/Omega_Centauri/3RmIlFJu">Omega Centauri</a> (one of the largest-known <a href="/facts/Globular_cluster/FL0EERJU">globular clusters</a>, perhaps containing over a million <a href="/facts/Star/PFbd6ICx">stars</a>)<a class="footnote-ref" id="fnref:235" href="#fn:235"><sup>235</sup></a><a class="footnote-ref" id="fnref:236" href="#fn:236"><sup>236</sup></a></li> <li>3.08568 Em – 326.1 light-years – 1 hectoparsec</li> <li>3.1 Em – 310 light-years – distance to <a href="/facts/Canopus_(star)/zD5WcDy5">Canopus</a> according to <i><a href="/facts/Hipparcos/Th2HW7VN">Hipparcos</a></i><a class="footnote-ref" id="fnref:237" href="#fn:237"><sup>237</sup></a></li> <li>3.9 Em – 410 light-years – distance to <a href="/facts/Betelgeuse/BsD9Ap7C">Betelgeuse</a> according to <i>Hipparcos</i><a class="footnote-ref" id="fnref:238" href="#fn:238"><sup>238</sup></a></li> <li>6.2 Em – 650 light-years – distance to the <a href="/facts/Helix_Nebula/PFUtF3so">Helix Nebula</a>, located in the constellation <a href="/facts/Aquarius_(constellation)/FrYyKIUv">Aquarius</a><a class="footnote-ref" id="fnref:239" href="#fn:239"><sup>239</sup></a></li> <li>8.2 Em – 860 light-years – distance to <a href="/facts/Rigel/WeeIXAAv">Rigel</a> according to <i>Hipparcos</i><a class="footnote-ref" id="fnref:240" href="#fn:240"><sup>240</sup></a></li> <li>9.4 Em — 1 light-millennium – 1000 light-years</li></ul> <h2 id="10-exameters">10 exameters</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Distance/hbXlaEFk">distances</a> starting at 10 <a href="/facts/Exametre/YzL1bHGX">Em</a> (1019 <a href="/facts/Metre/hPhzc1CV">m</a> or 1,100 <a href="/facts/Light-year/IGc5NdQb">light-years</a>). </p> <ul><li>10.6 Em – 1,120 light-years – distance to <a href="/facts/WASP-96b/TcrK05Wf">WASP-96b</a></li> <li>13 Em – 1,300 light-years – distance to the <a href="/facts/Orion_Nebula/6VWbcqzL">Orion Nebula</a><a class="footnote-ref" id="fnref:241" href="#fn:241"><sup>241</sup></a></li> <li>14 Em – 1,500 light-years – approximate thickness of the <a href="/facts/Galactic_plane/4eaqfCIB">plane</a> of the <a href="/facts/Milky_Way/ulF6lccN">Milky Way</a> <a href="/facts/Galaxy/zCyUvEf7">galaxy</a> at the <a href="/facts/Sun/CadPCVHh">Sun</a>'s location</li> <li>14.2 Em – 1,520 light-years – diameter of the <a href="/facts/NGC_604/26E8kTK8">NGC 604</a></li> <li>30.8568 Em – 3,261.6 light-years – 1 <a href="/facts/Parsec/SwSsk57J">kiloparsec</a></li> <li>31 Em – 3,200 light-years – distance to <a href="/facts/Deneb/L7dTfcog">Deneb</a> according to <i><a href="/facts/Hipparcos/Th2HW7VN">Hipparcos</a></i></li> <li>46 Em – 4,900 light-years – distance to <a href="/facts/OGLE-TR-56/d68RkJ3S">OGLE-TR-56</a>, the first <a href="/facts/Extrasolar_planet/zjfmqfUf">extrasolar planet</a> discovered using the <a href="/facts/Extrasolar_planet/zjfmqfUf">transit method</a></li> <li>47 Em – 5,000 light-years – distance to the <a href="/facts/Boomerang_nebula/KP38PtA2">Boomerang nebula</a>, coldest place known (<a href="/facts/1_E0_K/ADXGAk8e">1 K</a>)</li> <li>53 Em – 5,600 light-years – distance to the <a href="/facts/Globular_cluster/FL0EERJU">globular cluster</a> <a href="/facts/Messier_4/alBzC4zT">M4</a> and the <a href="/facts/Extrasolar_planet/zjfmqfUf">extrasolar planet</a> <a href="/facts/PSR_B1620-26_b/8rltJ0MG">PSR B1620-26 b</a> within it</li> <li>61 Em – 6,500 light-years – distance to <a href="/facts/Perseus_Spiral_Arm/lm1TFb0z">Perseus Spiral Arm</a> (next spiral arm out in the Milky Way galaxy)</li> <li>71 Em – 7,500 light-years – distance to <a href="/facts/Eta_Carinae/zsrmE2Lo">Eta Carinae</a></li> <li>94.6073 Em – 1 light-decamillennium = 10,000 light-years</li></ul> <h2 id="100-exameters">100 exameters</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Distance/hbXlaEFk">distances</a> starting at 100 <a href="/facts/Exametre/YzL1bHGX">Em</a> (1020 <a href="/facts/Metre/hPhzc1CV">m</a> or 11,000 <a href="/facts/Light-year/IGc5NdQb">light-years</a>). </p> <ul><li>150 Em – 16,000 light-years – diameter of the <a href="/facts/Small_Magellanic_Cloud/jg9s2YCl">Small Magellanic Cloud</a>, a <a href="/facts/Dwarf_galaxy/TKS7W9tA">dwarf galaxy</a> orbiting the <a href="/facts/Milky_Way/ulF6lccN">Milky Way</a></li> <li>200 Em – 21,500 light-years – distance to <a href="/facts/OGLE-2005-BLG-390Lb/s0Wj7SaK">OGLE-2005-BLG-390Lb</a></li> <li>240 Em – 25,000 light-years – distance to the <a href="/facts/Canis_Major_Dwarf_Galaxy/uQjxtxef">Canis Major Dwarf Galaxy</a></li> <li>260 Em – 28,000 light-years – distance to the center of the <a href="/facts/Milky_Way/ulF6lccN">Galaxy</a></li> <li>400 Em – 48,000 light years – diameter of the <a href="/facts/Fireworks_Galaxy/2RWdwP4e">Fireworks Galaxy</a></li> <li>830 Em – 88,000 light-years – distance to the <a href="/facts/Sagittarius_Dwarf_Elliptical_Galaxy/9IfJCbtl">Sagittarius Dwarf Elliptical Galaxy</a></li> <li>946 Em – 1 light-centum-millennium = 100,000 light-years</li></ul> <h2 id="1-zettameter">1 zettameter</h2> <p>The <i>zettametre</i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>Zm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 1021 <a href="/facts/Metre/hPhzc1CV">meters</a>.<a class="footnote-ref" id="fnref:242" href="#fn:242"><sup>242</sup></a> To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Distance/hbXlaEFk">distances</a> starting at 1 <a href="/facts/Zettametre/YzL1bHGX">Zm</a> (1021 <a href="/facts/Metre/hPhzc1CV">m</a> or 110,000 <a href="/facts/Light-year/IGc5NdQb">light-years</a>). </p> <ul><li>1.7 Zm – 179,000 light-years – distance to the <a href="/facts/Large_Magellanic_Cloud/7VYAehNa">Large Magellanic Cloud</a>, largest <a href="/facts/Satellite_galaxy/FMSSSqrc">satellite galaxy</a> of the <a href="/facts/Milky_Way/ulF6lccN">Milky Way</a></li> <li><1.9 Zm – <200,000 light-years – revised estimated diameter of the disc of the <a href="/facts/Milky_Way/ulF6lccN">Milky Way Galaxy</a>. The size was previously thought to be half of this.</li> <li>2.0 Zm – 210,000 light-years – distance to the <a href="/facts/Small_Magellanic_Cloud/jg9s2YCl">Small Magellanic Cloud</a></li> <li>2.8 Zm – 300,000 light-years – distance to the <a href="/facts/Intergalactic_Wanderer/3p4HyY9S">Intergalactic Wanderer</a>, one of the most distant <a href="/facts/Globular_cluster/FL0EERJU">globular clusters</a> of Milky Way</li> <li>8.5 Zm – 900,000 light-years – distance to the <a href="/facts/Leo_I_Dwarf_Galaxy/DS31oPfz">Leo I Dwarf Galaxy</a>, farthest-known <a href="/facts/Milky_Way/ulF6lccN">Milky Way</a> satellite <a href="/facts/Galaxy/zCyUvEf7">galaxy</a></li></ul> <h2 id="10-zettameters">10 zettameters</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Distance/hbXlaEFk">distances</a> starting at 10 <a href="/facts/Zettametre/YzL1bHGX">Zm</a> (1022 <a href="/facts/Metre/hPhzc1CV">m</a> or 1.1 million <a href="/facts/Light-year/IGc5NdQb">light-years</a>). </p> <ul><li>24 Zm – 2.5 million light-years – distance to the <a href="/facts/Andromeda_Galaxy/MjmSLV6m">Andromeda Galaxy</a>, the nearest major <a href="/facts/Galaxy/zCyUvEf7">galaxy</a>.</li> <li>30.8568 Zm – 3.2616 million light-years – 1 <a href="/facts/Parsec/SwSsk57J">megaparsec</a></li> <li>40 Zm – 4.2 million light-years – distance to the <a href="/facts/IC_10/J7QKHLoU">IC 10</a>, a distant member of the <a href="/facts/Local_Group/kjUefCLr">Local Group</a> of <a href="/facts/Galaxy/zCyUvEf7">galaxies</a></li> <li>49.2 Zm – 5.2 million light-years – width of the <a href="/facts/Local_Group/kjUefCLr">Local Group</a> of <a href="/facts/Galaxy/zCyUvEf7">galaxies</a></li> <li>95 Zm – 10 million light-years – distance to the <a href="/facts/Sculptor_Galaxy/sJswJu6M">Sculptor Galaxy</a> in the <a href="/facts/Sculptor_Group/HyDQI5By">Sculptor Group</a> of galaxies</li> <li>95 Zm – 10 million light-years – distance to the <a href="/facts/Maffei_1/h0180DBV">Maffei 1</a>, the nearest giant <a href="/facts/Elliptical_galaxy/1PUchrj1">elliptical galaxy</a> in the <a href="/facts/Maffei_1_group_of_galaxies/NeVcxnP8">Maffei 1 Group</a></li></ul> <h2 id="100-zettameters">100 zettameters</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Distance/hbXlaEFk">distances</a> starting at 100 <a href="/facts/Zettametre/YzL1bHGX">Zm</a> (1023 <a href="/facts/Metre/hPhzc1CV">m</a> or 11 million <a href="/facts/Light-year/IGc5NdQb">light-years</a>). </p> <ul><li>140 Zm – 15 million light-years – distance to <a href="/facts/Centaurus_A/gXJfrunq">Centaurus A</a> galaxy</li> <li>250 Zm – 27 million light-years – distance to the <a href="/facts/Pinwheel_Galaxy/RS5RoE0R">Pinwheel Galaxy</a></li> <li>280 Zm – 30 million light-years – distance to the <a href="/facts/Sombrero_Galaxy/snMpBeCb">Sombrero Galaxy</a></li> <li>570 Zm – 60 million light-years – approximate distance to the <a href="/facts/Virgo_cluster/dBsDKTzT">Virgo cluster</a>, nearest <a href="/facts/Galaxy_cluster/BhIEgbx8">galaxy cluster</a></li> <li>620 Zm – 65 million light-years – approximate distance to the <a href="/facts/Fornax_cluster/K2aydKYe">Fornax cluster</a></li> <li>800 Zm – 85 million light-years – approximate distance to the <a href="/facts/Eridanus_cluster/8k1BdprE">Eridanus cluster</a></li></ul> <h2 id="1-yottameter">1 yottameter</h2> <p>The <i>yottametre</i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>Ym</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 1024 <a href="/facts/Metre/hPhzc1CV">meters</a>.<a class="footnote-ref" id="fnref:243" href="#fn:243"><sup>243</sup></a> </p><p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Distance/hbXlaEFk">distances</a> starting at 1 Ym (1024 <a href="/facts/Metre/hPhzc1CV">m</a> or 105.702 million <a href="/facts/Light-year/IGc5NdQb">light-years</a>). </p> <ul><li>1.2 Ym – 127 million light-years – distance to the closest observed <a href="/facts/Gamma_ray_burst/oRRU6Fhn">gamma ray burst</a> <a href="/facts/GRB_980425/y1bG2uQ0">GRB 980425</a></li> <li>1.3 Ym – 137 million light-years – distance to the <a href="/facts/Centaurus_Cluster/by6LgAIP">Centaurus Cluster</a> of <a href="/facts/Galaxies/zCyUvEf7">galaxies</a>, the nearest large <a href="/facts/Supercluster/DIBrfG30">supercluster</a></li> <li>1.9 Ym – 201 million light-years – diameter of the <a href="/facts/Local_Supercluster/kUNskKbo">Local Supercluster</a></li> <li>2.17 Ym – 1 light-galactic-years – 230 million light-years</li> <li>2.3 Ym – 225 to 250 million light-years – distance light travels in vacuum in one <a href="/facts/Galactic_year/em3T4hXW">galactic year</a></li> <li>2.8 Ym – 296 million light-years – distance to the <a href="/facts/Coma_Cluster/k5Fw8qUH">Coma Cluster</a></li> <li>3.15 Ym – 330 million light years – diameter of the <a href="/facts/Bo%C3%B6tes_Void/6EReq3dl">Boötes Void</a></li> <li>3.2 Ym – 338 million light-years – distance to <a href="/facts/Stephan%27s_Quintet/EvEKHXLC">Stephan's Quintet</a></li> <li>4.7 Ym – 496 million light-years – length of the <a href="/facts/Great_Wall_(astronomy)/r8XpATsh">CfA2 Great Wall</a>, one of the largest observed superstructures in the <a href="/facts/Universe/XbfpnDmM">Universe</a></li> <li>6.1 Ym – 645 million light-years – distance to the <a href="/facts/Shapley_Supercluster/WohvR584">Shapley Supercluster</a></li> <li>9.5 Ym – 996 million light-years – diameter of the <a href="/facts/Eridanus_Supervoid/L3DVyTrm">Eridanus Supervoid</a></li></ul> <h2 id="10-yottameters">10 yottameters</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Distance/hbXlaEFk">distances</a> starting at 10 <a href="/facts/Yottametre/YzL1bHGX">Ym</a> (1025 <a href="/facts/Metre/hPhzc1CV">m</a> or 1.1 billion <a href="/facts/Light-year/IGc5NdQb">light-years</a>). At this scale, expansion of the <a href="/facts/Universe/XbfpnDmM">universe</a> becomes significant. Distance of these objects are derived from their measured <a href="/facts/Redshift/Qfl4VjDF">redshifts</a>, which depends on the <a href="/facts/Physical_cosmology/ww4ChbEq">cosmological</a> models used. </p> <ul><li>13 Ym – 1.37 billion light-years – length of the <a href="/facts/South_Pole_Wall/fdezpyIb">South Pole Wall</a></li> <li>13 Ym – 1.38 billion light-years – length of the <a href="/facts/Sloan_Great_Wall/ISF27bp0">Sloan Great Wall</a></li> <li>18 Ym – redshift 0.16 – 1.9 billion light-years – distance to the <a href="/facts/Quasar/HS96328l">quasar</a> <a href="/facts/3C_273/P11TI6Ez">3C 273</a> (<a href="/facts/Distance_measures_(cosmology)/EYsRSlep">light travel distance</a>)</li> <li>30.8568 Ym – 3.2616 billion light-years – 1 gigaparsec</li> <li>31.2204106 Ym − 3.3 billion light-years − length of <a href="/facts/The_Giant_Arc/SFwo3Thb">The Giant Arc</a>, a large cosmic structure discovered in 2021</li> <li>33 Ym – 3.5 billion light-years – maximum distance of the <a href="/facts/2dF_Galaxy_Redshift_Survey/zSPHQtLc">2dF Galaxy Redshift Survey</a> (light travel distance)</li> <li>37.8 Ym – 4 billion light-years – length of the <a href="/facts/Huge-LQG/XGTJwRvR">Huge-LQG</a></li> <li>75 Ym – redshift 0.95 – 8 billion light-years – approximate distance to the <a href="/facts/Supernova/Pfo2J23l">supernova</a> SN 2002dd in the <a href="/facts/Hubble_Deep_Field_North/Auz98FQg">Hubble Deep Field North</a> (light travel distance)</li> <li>85 Ym – redshift 1.6 – 9 billion light-years – approximate distance to the <a href="/facts/Gamma-ray_burst/oRRU6Fhn">gamma-ray burst</a> <a href="/facts/GRB_990123/N8cPRaB1">GRB 990123</a> (light travel distance)</li> <li>94.6 Ym – 10 billion light-years – approximate distance to quasar OQ172</li> <li>94.6 Ym – 10 billion light-years – length of the <a href="/facts/Hercules%E2%80%93Corona_Borealis_Great_Wall/kszfcMlc">Hercules–Corona Borealis Great Wall</a>, one of the <a href="/facts/List_of_largest_cosmic_structures/amD8w2ID">largest and most massive-known cosmic structures known</a></li></ul> <h2 id="100-yottameters">100 yottameters</h2> <p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Distance/hbXlaEFk">distances</a> starting at 100 <a href="/facts/Yottametre/YzL1bHGX">Ym</a> (1026 <a href="/facts/Metre/hPhzc1CV">m</a> or 11 billion <a href="/facts/Light-year/IGc5NdQb">light-years</a>). At this scale, expansion of the <a href="/facts/Universe/XbfpnDmM">universe</a> becomes significant. Distance of these objects are derived from their measured <a href="/facts/Redshift/Qfl4VjDF">redshifts</a>, which depend on the <a href="/facts/Physical_cosmology/ww4ChbEq">cosmological</a> models used. </p> <ul><li>124 Ym – redshift 7.54 – 13.1 billion light-years – <a href="/facts/Distance_measures_(cosmology)/EYsRSlep">light travel distance</a> (LTD) to the <a href="/facts/Quasar/HS96328l">quasar</a> <a href="/facts/ULAS_J1342%2B0928/pSjNQXXe">ULAS J1342+0928</a>, the <a href="/facts/List_of_quasars/coI3R8w7">most distant-known quasar</a> as of 2017</li> <li>130 Ym – redshift 1,000 – 13.8 billion light-years – distance (LTD) to the source of the <a href="/facts/Cosmic_microwave_background/ThB2HkLS">cosmic microwave background radiation</a>; radius of the observable <a href="/facts/Universe/XbfpnDmM">universe</a> measured as a LTD</li> <li>260 Ym – 27.4 billion light-years – diameter of the observable universe (double LTD)</li> <li>440 Ym – 46 billion light-years – radius of the universe measured as a <a href="/facts/Comoving_distance/55cYbfbY">comoving distance</a></li> <li>590 Ym – 62 billion light-years – cosmological <a href="/facts/Event_horizon/KXH2ptnI">event horizon</a>: the largest comoving distance from which light will ever reach us (the observer) at any time in the future</li> <li>886.48 Ym – 93.7 billion light-years – the diameter of the <a href="/facts/Observable_universe/CdTGMdsp">observable universe</a> (twice the <a href="/facts/Particle_horizon/sxfNTy8E">particle horizon</a>); however, there might be unobserved distances that are even greater.</li></ul> <h2 id="1-ronnameter">1 ronnameter</h2> <p>The <i>ronnametre</i> (<a href="/facts/SI/NShmfzlD">SI</a> symbol: <i>Rm</i>) is a <a href="/facts/Units_of_measurement/pvTpWbmC">unit</a> of <a href="/facts/Length/EwFyAqGH">length</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> equal to 1027 <a href="/facts/Metre/hPhzc1CV">meters</a>.<a class="footnote-ref" id="fnref:244" href="#fn:244"><sup>244</sup></a> </p><p>To help compare different <a href="/facts/Orders_of_magnitude/cWzRP2dM">orders of magnitude</a>, this section lists <a href="/facts/Distance/hbXlaEFk">distances</a> starting at 1 Rm (1027 <a href="/facts/Metre/hPhzc1CV">m</a> or 105.7 billion <a href="/facts/Light-year/IGc5NdQb">light-years</a>). At this scale, expansion of the <a href="/facts/Universe/XbfpnDmM">universe</a> becomes significant. Distance of these objects are derived from their measured <a href="/facts/Redshift/Qfl4VjDF">redshifts</a>, which depend on the <a href="/facts/Physical_cosmology/ww4ChbEq">cosmological</a> models used. </p> <ul><li>>1 Rm – >105.7 billion light-years – size of universe beyond the <a href="/facts/Observable_universe/CdTGMdsp">cosmic light horizon</a>, depending on its curvature; if the curvature is zero (i.e. the universe is spatially flat), the value can be <a href="/facts/Infinity/cF506uD7">infinite</a> (see <a href="/facts/Shape_of_the_universe/EJFEm9bw">Shape of the universe</a>) as previously mentioned.</li> <li>2.764 Rm - 292.2 billion light-years – circumference of the observable universe, as it is in the shape of a sphere.</li> <li>≈101010122<a href="/facts/Light-year/IGc5NdQb">light-years</a> – the possible size of the universe after <a href="/facts/Cosmological_inflation/SujXx3aD">cosmological inflation</a>.</li> <li>≈∞ light-years – theoretical size of the <a href="/facts/Multiverse/GUCDxvPg">multiverse</a> if it exists.</li></ul> <h2 id="see-also">See also</h2> <ul><li><a href="/facts/Fermi_problem/LueugRQk">Fermi problem</a></li> <li><a href="/facts/Scale_(analytical_tool)/AWAqwh2W">Scale (analytical tool)</a></li> <li><a href="/facts/Spatial_scale/Q96HPqcY">Spatial scale</a></li> <li><a href="/facts/The_Scale_of_the_Universe/R9L7bVXK">The Scale of the Universe</a></li></ul> <h2 id="notes">Notes</h2> <h2 id="external-links">External links</h2> <ul><li><a href="http://www.vendian.org/howbig/">How Big Are Things?</a> – displays orders of magnitude in successively larger rooms.</li> <li><a href="https://web.archive.org/web/20120702055359/http://microcosm.web.cern.ch/microcosm/P10/english/welcome.html">Powers of Ten</a> – Travel across the Universe.</li> <li><a href="https://web.archive.org/web/20080412094332/http://www.shekpvar.net/~dna/Publications/Cosmos/cosmos.html">Cosmos – Journey from microcosmos to macrocosmos</a> (Digital Nature Agency).</li> <li><a href="http://htwins.net/scale2/">Scale of the universe</a> – interactive guide to length magnitudes</li> <li><a href="https://www.youtube.com/watch?v=FglEbPXxka4">Video (4:29)</a> on <a href="/facts/YouTube_video_(identifier)/db276jst">YouTube</a> – <a href="https://venturebeat.com/2020/03/16/orders-of-magnitude-vr-reveals-humanitys-tiny-scale-in-the-universe/">Orders of Magnitude</a> (March 2020).</li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>The diameter of human hair ranges from 17 to 181 μm Ley, Brian (1999). Elert, Glenn (ed.). "Diameter of a human hair". The Physics Factbook. Retrieved 8 December 2018. <a href="/wiki/Diameter" target="_blank">/wiki/Diameter</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>Burgess, Cliff; Quevedo, Fernando (November 2007). "The Great Cosmic Roller-Coaster Ride". Scientific American. 297 (5): 55. Bibcode:2007SciAm.297e..52B. doi:10.1038/scientificamerican1107-52 (inactive 2 November 2024). PMID 17990824. Retrieved 1 May 2017.{{cite journal}}: CS1 maint: DOI inactive as of November 2024 (link) <a href="/wiki/Fernando_Quevedo" target="_blank">/wiki/Fernando_Quevedo</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>Nave, Carl R. "Cowan and Reines Neutrino Experiment". HyperPhysics. Retrieved 4 December 2008. (6.3 × 10−44 cm2, which gives an effective radius of about 1.42 × 10−22 m) <a href="http://hyperphysics.phy-astr.gsu.edu/hbase/particles/cowan.html#c1" target="_blank">http://hyperphysics.phy-astr.gsu.edu/hbase/particles/cowan.html#c1</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>Nave, Carl R. "Neutron Absorption Cross-sections". HyperPhysics. Retrieved 4 December 2008. (area for 20 GeV about 10 × 10−42 m2 gives effective radius of about 2 × 10−21 m; for 250 GeV about 150 × 10−42 m2 gives effective radius of about 7 × 10−21 m) <a href="http://hyperphysics.phy-astr.gsu.edu/hbase/particles/neutrino3.html#c2" target="_blank">http://hyperphysics.phy-astr.gsu.edu/hbase/particles/neutrino3.html#c2</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>Abbott, B. P.; et al. (2016). "Observation of Gravitational Waves from a Binary Black Hole Merger". Physical Review Letters. 116 (6): 061102. arXiv:1602.03837. Bibcode:2016PhRvL.116f1102A. doi:10.1103/PhysRevLett.116.061102. PMID 26918975. S2CID 124959784. On 14 September 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0×10−21. <a href="/wiki/ArXiv_(identifier)" target="_blank">/wiki/ArXiv_(identifier)</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>Burgess, Cliff; Quevedo, Fernando (November 2007). "The Great Cosmic Roller-Coaster Ride". Scientific American. 297 (5): 55. Bibcode:2007SciAm.297e..52B. doi:10.1038/scientificamerican1107-52 (inactive 2 November 2024). PMID 17990824. Retrieved 1 May 2017.{{cite journal}}: CS1 maint: DOI inactive as of November 2024 (link) <a href="/wiki/Fernando_Quevedo" target="_blank">/wiki/Fernando_Quevedo</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> <li id="fn:7"><p>Pohl, R.; et al. (July 2010). "The size of the proton". Nature. 466 (7303): 213–6. Bibcode:2010Natur.466..213P. doi:10.1038/nature09250. PMID 20613837. S2CID 4424731. <a href="https://rdcu.be/bYa2m" target="_blank">https://rdcu.be/bYa2m</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li> <li id="fn:8"><p>Strassler, Matt (30 May 2013). "The strength of the known forces". profmattstrassler.com. <a href="/wiki/Matt_Strassler" target="_blank">/wiki/Matt_Strassler</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></p></li> <li id="fn:9"><p>Kolena. "The four forces: The strong interaction". Astrophysics Dept website. Duke University. <a href="http://webhome.phy.duke.edu/~kolena/modern/forces.html#005" target="_blank">http://webhome.phy.duke.edu/~kolena/modern/forces.html#005</a> <a href="#fnref:9" class="footnote-back-ref">↩</a></p></li> <li id="fn:10"><p>Nave, Carl R. "Scattering cross section". Retrieved 10 February 2009. (diameter of the scattering cross section of an 11 MeV proton with a target proton) <a href="http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/crosec.html" target="_blank">http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/crosec.html</a> <a href="#fnref:10" class="footnote-back-ref">↩</a></p></li> <li id="fn:11"><p>"CODATA Value: classical electron radius". The NIST Reference on Constants, Units, and Uncertainty. NIST. <a href="https://physics.nist.gov/cgi-bin/cuu/Value?re" target="_blank">https://physics.nist.gov/cgi-bin/cuu/Value?re</a> <a href="#fnref:11" class="footnote-back-ref">↩</a></p></li> <li id="fn:12"><p>Strassler, Matt (30 May 2013). 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S2CID 10340205. <a href="/wiki/ArXiv_(identifier)" target="_blank">/wiki/ArXiv_(identifier)</a> <a href="#fnref:217" class="footnote-back-ref">↩</a></p></li> <li id="fn:218"><p>Woodruff, H. C.; Eberhardt, M.; Driebe, T.; Hofmann, K.-H.; Ohnaka, K.; Richichi, A.; Schertl, D.; Schoeller, M.; Scholz, M.; Weigelt, G.; Wittkowski, M.; Wood, P. R. (July 2004). "Interferometric observations of the Mira star o Ceti with the VLTI/VINCI instrument in the near-infrared". Astronomy & Astrophysics. 421 (2): 703–714. arXiv:astro-ph/0404248. Bibcode:2004A&A...421..703W. doi:10.1051/0004-6361:20035826. ISSN 0004-6361. <a href="/wiki/ArXiv_(identifier)" target="_blank">/wiki/ArXiv_(identifier)</a> <a href="#fnref:218" class="footnote-back-ref">↩</a></p></li> <li id="fn:219"><p>Lau, R. M.; Herter, T. L.; Morris, M. R.; Adams, J. D. (2014). "Nature Versus Nurture: Luminous Blue Variable Nebulae in and Near Massive Stellar Clusters at the Galactic Center". The Astrophysical Journal. 785 (2): 120. arXiv:1403.5298. Bibcode:2014ApJ...785..120L. doi:10.1088/0004-637X/785/2/120. S2CID 118447462. <a href="/wiki/ArXiv_(identifier)" target="_blank">/wiki/ArXiv_(identifier)</a> <a href="#fnref:219" class="footnote-back-ref">↩</a></p></li> <li id="fn:220"><p>Anugu, Narsireddy; Baron, Fabien; Monnier, John D.; Gies, Douglas R.; Roettenbacher, Rachael M.; Schaefer, Gail H.; Montargès, Miguel; Kraus, Stefan; Bouquin, Jean-Baptiste Le (5 August 2024). "CHARA Near-Infrared Imaging of the Yellow Hypergiant Star $\rho$ Cassiopeiae: Convection Cells and Circumstellar Envelope". arXiv:2408.02756v2 [astro-ph.SR]. <a href="/wiki/ArXiv_(identifier)" target="_blank">/wiki/ArXiv_(identifier)</a> <a href="#fnref:220" class="footnote-back-ref">↩</a></p></li> <li id="fn:221"><p>Joyce, Meridith; Leung, Shing-Chi; Molnár, László; Ireland, Michael; Kobayashi, Chiaki; Nomoto, Ken'Ichi (2020). "Standing on the Shoulders of Giants: New Mass and Distance Estimates for Betelgeuse through Combined Evolutionary, Asteroseismic, and Hydrodynamic Simulations with MESA". The Astrophysical Journal. 902 (1): 63. arXiv:2006.09837. Bibcode:2020ApJ...902...63J. doi:10.3847/1538-4357/abb8db. <a href="https://doi.org/10.3847%2F1538-4357%2Fabb8db" target="_blank">https://doi.org/10.3847%2F1538-4357%2Fabb8db</a> <a href="#fnref:221" class="footnote-back-ref">↩</a></p></li> <li id="fn:222"><p>Gull, Theodore R.; Hillier, D. John; Hartman, Henrik; Corcoran, Michael F.; Damineli, Augusto; Espinoza-Galeas, David; Hamaguchi, Kenji; Navarete, Felipe; Nielsen, Krister; Madura, Thomas; Moffat, Anthony F. J.; Morris, Patrick; Richardson, Noel D.; Russell, Christopher M. P.; Stevens, Ian R. (July 2022). "Eta Carinae: An Evolving View of the Central Binary, Its Interacting Winds and Its Foreground Ejecta". The Astrophysical Journal. 933 (2): 175. arXiv:2205.15116. Bibcode:2022ApJ...933..175G. doi:10.3847/1538-4357/ac74c2. ISSN 0004-637X. <a href="https://doi.org/10.3847%2F1538-4357%2Fac74c2" target="_blank">https://doi.org/10.3847%2F1538-4357%2Fac74c2</a> <a href="#fnref:222" class="footnote-back-ref">↩</a></p></li> <li id="fn:223"><p>Munoz-Sanchez, G.; Kalitsounaki, M.; Wit, S. de; Antoniadis, K.; Bonanos, A. Z.; Zapartas, E.; Boutsia, K.; Christodoulou, E.; Maravelias, G. (2 December 2024), The dramatic transition of the extreme Red Supergiant WOH G64 to a Yellow Hypergiant, arXiv:2411.19329 <a href="/wiki/ArXiv_(identifier)" target="_blank">/wiki/ArXiv_(identifier)</a> <a href="#fnref:223" class="footnote-back-ref">↩</a></p></li> <li id="fn:224"><p>van Genderen, A. M.; Lobel, A.; Nieuwenhuijzen, H.; Henry, G. W.; De Jager, C.; Blown, E.; Di Scala, G.; Van Ballegoij, E. J. (2019). "Pulsations, eruptions, and evolution of four yellow hypergiants". Astronomy and Astrophysics. 631: A48. arXiv:1910.02460. Bibcode:2019A&A...631A..48V. doi:10.1051/0004-6361/201834358. S2CID 203836020. <a href="/wiki/ArXiv_(identifier)" target="_blank">/wiki/ArXiv_(identifier)</a> <a href="#fnref:224" class="footnote-back-ref">↩</a></p></li> <li id="fn:225"><p>Bauer, W. H.; Gull, T. R.; Bennett, P. D. (2008). "Spatial Extension in the Ultraviolet Spectrum of Vv Cephei". The Astronomical Journal. 136 (3): 1312. Bibcode:2008AJ....136.1312H. doi:10.1088/0004-6256/136/3/1312. S2CID 119404901. <a href="https://doi.org/10.1088%2F0004-6256%2F136%2F3%2F1312" target="_blank">https://doi.org/10.1088%2F0004-6256%2F136%2F3%2F1312</a> <a href="#fnref:225" class="footnote-back-ref">↩</a></p></li> <li id="fn:226"><p>Table 4 in Emily M. Levesque; Philip Massey; K. A. G. Olsen; Bertrand Plez; Eric Josselin; Andre Maeder & Georges Meynet (2005). "The Effective Temperature Scale of Galactic Red Supergiants: Cool, but Not As Cool As We Thought". The Astrophysical Journal. 628 (2): 973–985. arXiv:astro-ph/0504337. Bibcode:2005ApJ...628..973L. doi:10.1086/430901. S2CID 15109583. <a href="/wiki/Emily_Levesque" target="_blank">/wiki/Emily_Levesque</a> <a href="#fnref:226" class="footnote-back-ref">↩</a></p></li> <li id="fn:227"><p>Shenoy, Dinesh; Humphreys, Roberta M.; Jones, Terry J.; Marengo, Massimo; Gehrz, Robert D.; Helton, L. Andrew; Hoffmann, William F.; Skemer, Andrew J.; Hinz, Philip M. (2016). "SEARCHING FOR COOL DUST IN THE MID-TO-FAR INFRARED: THE MASS-LOSS HISTORIES OF THE HYPERGIANTS μ Cep, VY CMa, IRC+10420, AND ρ Cas". The Astronomical Journal. 151 (3): 51. arXiv:1512.01529. Bibcode:2016AJ....151...51S. doi:10.3847/0004-6256/151/3/51. <a href="https://doi.org/10.3847%2F0004-6256%2F151%2F3%2F51" target="_blank">https://doi.org/10.3847%2F0004-6256%2F151%2F3%2F51</a> <a href="#fnref:227" class="footnote-back-ref">↩</a></p></li> <li id="fn:228"><p>Wittkowski, M.; Hauschildt, P.H.; Arroyo-Torres, B.; Marcaide, J.M. (5 April 2012). "Fundamental properties and atmospheric structure of the red supergiant VY CMa based on VLTI/AMBER spectro-interferometry". Astronomy & Astrophysics. 540: L12. arXiv:1203.5194. Bibcode:2012A&A...540L..12W. doi:10.1051/0004-6361/201219126. S2CID 54044968. <a href="/wiki/ArXiv_(identifier)" target="_blank">/wiki/ArXiv_(identifier)</a> <a href="#fnref:228" class="footnote-back-ref">↩</a></p></li> <li id="fn:229"><p>Parthasarathy, M. (2000). "Birth and early evolution of planetary nebulae". Bulletin of the Astronomical Society of India. 28: 217–224. Bibcode:2000BASI...28..217P. <a href="/wiki/Bibcode_(identifier)" target="_blank">/wiki/Bibcode_(identifier)</a> <a href="#fnref:229" class="footnote-back-ref">↩</a></p></li> <li id="fn:230"><p>radius = distance times sin(angular diameter/2) = 0.2 light-year. Distance = 3.3 ± 0.9 kly; angular diameter = 20 arcseconds (Reed et al. 1999) <a href="/wiki/Light-year" target="_blank">/wiki/Light-year</a> <a href="#fnref:230" class="footnote-back-ref">↩</a></p></li> <li id="fn:231"><p>Reed, Darren S.; Balick, Bruce; Hajian, Arsen R.; Klayton, Tracy L.; Giovanardi, Stefano; Casertano, Stefano; Panagia, Nino; Terzian, Yervant (1999). "Hubble Space Telescope Measurements of the Expansion of NGC 6543: Parallax Distance and Nebular Evolution". Astronomical Journal. 118 (5): 2430–2441. arXiv:astro-ph/9907313. Bibcode:1999AJ....118.2430R. doi:10.1086/301091. S2CID 14746840. <a href="/wiki/ArXiv_(identifier)" target="_blank">/wiki/ArXiv_(identifier)</a> <a href="#fnref:231" class="footnote-back-ref">↩</a></p></li> <li id="fn:232"><p>Szpir, Michael (May–June 2001). "Bart Bok's Black Blobs". American Scientist. Archived from the original on 29 June 2003. Retrieved 19 November 2008. Bok globules such as Barnard 68 are only about half a light-year across and weigh in at about two solar masses <a href="https://web.archive.org/web/20030629033609/http://www.americanscientist.org/template/AssetDetail/assetid/14678" target="_blank">https://web.archive.org/web/20030629033609/http://www.americanscientist.org/template/AssetDetail/assetid/14678</a> <a href="#fnref:232" class="footnote-back-ref">↩</a></p></li> <li id="fn:233"><p>Sandstrom, Karin M; Peek, J. E. G.; Bower, Geoffrey C.; Bolatto, Alberto D.; Plambeck, Richard L. (1999). "A Parallactic Distance of 389+24−21 parsecs to the Orion Nebula Cluster from Very Long Baseline Array Observations". The Astrophysical Journal. 667 (2): 1161–1169. arXiv:0706.2361. Bibcode:2007ApJ...667.1161S. doi:10.1086/520922. S2CID 18192326. <a href="/wiki/ArXiv_(identifier)" target="_blank">/wiki/ArXiv_(identifier)</a> <a href="#fnref:233" class="footnote-back-ref">↩</a></p></li> <li id="fn:234"><p>diameter=sin(65 arcminutes)*1270 light-years=24; where "65.00 × 60.0 (arcmin)" sourced from Revised NGC Data for NGC 1976 <a href="https://web.archive.org/web/20120318092511/http://spider.seds.org/ngc/revngcic.cgi?NGC1976" target="_blank">https://web.archive.org/web/20120318092511/http://spider.seds.org/ngc/revngcic.cgi?NGC1976</a> <a href="#fnref:234" class="footnote-back-ref">↩</a></p></li> <li id="fn:235"><p>distance × sin( diameter_angle ), using distance of 5kpc (15.8 ± 1.1 kly) and angle 36.3', = 172 ± 12.5 ly. <a href="#fnref:235" class="footnote-back-ref">↩</a></p></li> <li id="fn:236"><p>van de Ven, G.; van den Bosch, R. C. E.; Verolme, E. K.; de Zeeuw, P. T. (2006). "The dynamical distance and intrinsic structure of the globular cluster ω Centauri". Astronomy and Astrophysics. 445 (2): 513–543. arXiv:astro-ph/0509228. Bibcode:2006A&A...445..513V. doi:10.1051/0004-6361:20053061. S2CID 15538249. best-fit dynamical distance D=4.8±0.3 kpc ... consistent with the canonical value 5.0±0.2 kpc obtained by photometric methods <a href="/wiki/Astronomy_and_Astrophysics" target="_blank">/wiki/Astronomy_and_Astrophysics</a> <a href="#fnref:236" class="footnote-back-ref">↩</a></p></li> <li id="fn:237"><p>van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600. Vizier catalog entry <a href="/wiki/ArXiv_(identifier)" target="_blank">/wiki/ArXiv_(identifier)</a> <a href="#fnref:237" class="footnote-back-ref">↩</a></p></li> <li id="fn:238"><p>Neuhäuser, R; Torres, G; Mugrauer, M; Neuhäuser, D L; Chapman, J; Luge, D; Cosci, M (29 July 2022). 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Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600. Vizier catalog entry <a href="/wiki/ArXiv_(identifier)" target="_blank">/wiki/ArXiv_(identifier)</a> <a href="#fnref:240" class="footnote-back-ref">↩</a></p></li> <li id="fn:241"><p>Reid, M. J.; et al. (2009). "Trigonometric Parallaxes of Massive Star Forming Regions: VI. Galactic Structure, Fundamental Parameters and Non-Circular Motions". Astrophysical Journal. 700 (1): 137–148. arXiv:0902.3913. Bibcode:2009ApJ...700..137R. doi:10.1088/0004-637X/700/1/137. S2CID 11347166. <a href="/wiki/Astrophysical_Journal" target="_blank">/wiki/Astrophysical_Journal</a> <a href="#fnref:241" class="footnote-back-ref">↩</a></p></li> <li id="fn:242"><p>"SI Brochure: The International System of Units (SI)". International Committee for Weights and Measures. Organisation Intergouvernementale de la Convention du Mètre. Retrieved 11 October 2014. <a href="https://www.bipm.org/en/publications/si-brochure/" target="_blank">https://www.bipm.org/en/publications/si-brochure/</a> <a href="#fnref:242" class="footnote-back-ref">↩</a></p></li> <li id="fn:243"><p>"SI Brochure: The International System of Units (SI)". International Committee for Weights and Measures. Organisation Intergouvernementale de la Convention du Mètre. Retrieved 11 October 2014. <a href="https://www.bipm.org/en/publications/si-brochure/" target="_blank">https://www.bipm.org/en/publications/si-brochure/</a> <a href="#fnref:243" class="footnote-back-ref">↩</a></p></li> <li id="fn:244"><p>"SI Brochure: The International System of Units (SI)". International Committee for Weights and Measures. Organisation Intergouvernementale de la Convention du Mètre. 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