Orbital pole

An orbital pole is either point at the ends of the orbital normal, an imaginary <a href="/facts/Line_segment/V8E0M4qk">line segment</a> that runs through a <a href="/facts/Focus_(geometry)/WFtFnqoa">focus</a> of an <a href="/facts/Orbit/nD2TPySG">orbit</a> (of a revolving body like a <a href="/facts/Planet/rbPjE6Bx">planet</a>, <a href="/facts/Natural_satellite/AE4KQKbq">moon</a> or <a href="/facts/Satellite/PTX8c68t">satellite</a>) and is <a href="/facts/Perpendicular/u0k8xqx4">perpendicular</a> (or <a href="/facts/Normal_(geometry)/jhtLIhcu">normal</a>) to the <a href="/facts/Orbital_plane/xPdMmVKP">orbital plane</a>. Projected onto the <a href="/facts/Celestial_sphere/TYAtXgor">celestial sphere</a>, orbital poles are similar in concept to <a href="/facts/Celestial_pole/5Gj9JJbK">celestial poles</a>, but are based on the body's orbit instead of its <a href="/facts/Celestial_equator/P9Lyq2DE">equator</a>.
The <a href="/facts/North/Hty6w98C">north</a> orbital pole of a revolving body is defined by the <a href="/facts/Right-hand_rule/LJe0Qqh4">right-hand rule</a>. If the fingers of the right hand are curved along the <a href="/facts/Retrograde_and_prograde_motion/1HCbwQqy">direction of orbital motion</a>, with the thumb extended and oriented to be parallel to the orbital <a href="/facts/Axis_of_rotation/PGcg3IY5">axis</a>, then the direction the thumb points is defined to be the orbital north.
The poles of <a href="/facts/Earth%2527s_orbit/BGGCdFag">Earth's orbit</a> are referred to as the <a href="/facts/Ecliptic/cJxXDDDW">ecliptic</a> poles. For the remaining planets, the orbital pole in <a href="/facts/Ecliptic_coordinates/28zkWwVa">ecliptic coordinates</a> is given by the <a href="/facts/Longitude_of_the_ascending_node/926pTlve">longitude of the ascending node</a> (☊) and <a href="/facts/Inclination/TQCFWyfd">inclination</a> (i): ℓ = ☊ − 90° , b = 90° − i . In the following table, the planetary orbit poles are given in both celestial coordinates and the ecliptic coordinates for the Earth.

<table><tbody><tr><th>Object</th><th><a href="/facts/Longitude_of_the_ascending_node/926pTlve">☊</a></th><th><a href="/facts/Inclination/TQCFWyfd">i</a></th><th><a href="/facts/Ecliptic_longitude/28zkWwVa">Ecl.Lon.</a></th><th><a href="/facts/Ecliptic_latitude/28zkWwVa">Ecl.Lat.</a></th><th><a href="/facts/Right_ascension/z4CEsTFu">RA (α)</a></th><th><a href="/facts/Declination/5X4S4k9u">Dec (δ)</a></th></tr><tr><td><a href="/facts/Mercury_(planet)/lVa1GIyX">Mercury</a></td><td>48.331°</td><td>7.005°</td><td>318.331°</td><td>82.995°</td><td>18h 43m 57.1s </td><td>+61° 26′ 52″</td></tr><tr><td><a href="/facts/Venus/pADnueP6">Venus</a></td><td>76.678°</td><td>3.395°</td><td>346.678°</td><td>86.605°</td><td>18h 32m 01.8s </td><td>+65° 34′ 01″</td></tr><tr><td><a href="/facts/Earth/HLLmDfj0">Earth</a></td><td>140°</td><td>0.0001°</td><td>50°</td><td>89.9999°</td><td>18h 00m 00.0s </td><td>+66° 33′ 38.84″</td></tr><tr><td><a href="/facts/Mars/AQGtVvz0">Mars</a></td><td>49.562°</td><td>1.850°</td><td>319.562°</td><td>88.150°</td><td>18h 13m 29.7s </td><td>+65° 19′ 22″</td></tr><tr><td><a href="/facts/Ceres_(dwarf_planet)/yIVEMYtG">Ceres</a></td><td>80.494°</td><td>10.583°</td><td>350.494°</td><td>79.417°</td><td>19h 33m 33.1s </td><td>+62° 50′ 57″</td></tr><tr><td><a href="/facts/Jupiter/95m7XjMT">Jupiter</a></td><td>100.492°</td><td>1.305°</td><td>10.492°</td><td>88.695°</td><td>18h 13m 00.8s </td><td>+66° 45′ 53″</td></tr><tr><td><a href="/facts/Saturn/D54LcGJ9">Saturn</a></td><td>113.643°</td><td>2.485°</td><td>23.643°</td><td>87.515°</td><td>18h 23m 46.8s </td><td>+67° 26′ 55″</td></tr><tr><td><a href="/facts/Uranus/x7YwT1ar">Uranus</a></td><td>73.989°</td><td>0.773°</td><td>343.989°</td><td>89.227°</td><td>18h 07m 24.1s </td><td>+66° 20′ 12″</td></tr><tr><td><a href="/facts/Neptune/1eucwHIC">Neptune</a></td><td>131.794°</td><td>1.768°</td><td>41.794°</td><td>88.232°</td><td>18h 13m 54.1s </td><td>+67° 42′ 08″</td></tr><tr><td><a href="/facts/Pluto/egq7MBeR">Pluto</a></td><td>110.287°</td><td>17.151°</td><td>20.287°</td><td>72.849°</td><td>20h 56m 3.7s </td><td>+66° 32′ 31″</td></tr></tbody></table>
When an <a href="/facts/Artificial_satellite/PTX8c68t">artificial satellite</a> orbits close to another large body, it can only maintain continuous observations in areas near its orbital poles. The continuous viewing zone (CVZ) of the <a href="/facts/Hubble_Space_Telescope/NQeIf0vw">Hubble Space Telescope</a> lies inside roughly 24° of Hubble's orbital poles, which <a href="/facts/Precession/44Sk1PMD">precess</a> around the Earth's axis every 56 days.

Orbital pole open-in-new

Orbital pole