Phase curve (astronomy)

<p>In <a href="/facts/Astronomy/0ArJVM1p">astronomy</a>, a phase curve describes the <a href="/facts/Brightness/e93R5I4b">brightness</a> of a reflecting <a href="/facts/Astronomical_object/BCHLa0Q2">body</a> as a function of its <a href="/facts/Phase_angle_(astronomy)/rPhG45gN">phase angle</a> (the arc <a href="/facts/Subtended/GQxln7lP">subtended</a> by the observer and the Sun as measured at the body). The brightness usually refers the object's <a href="/facts/Absolute_magnitude/R8RVxkLx">absolute magnitude</a>, which, in turn, is its <a href="/facts/Apparent_magnitude/7pCTF1Me">apparent magnitude</a> at a distance of one <a href="/facts/Astronomical_unit/gjsbu5xU">astronomical unit</a> from the Earth and Sun.
</p><p>The phase curve is useful for characterizing an object's <a href="/facts/Regolith/EdXuHK56">regolith</a> (soil) and <a href="/facts/Atmosphere/oUpLaGRF">atmosphere</a>. It is also the basis for computing the <a href="/facts/Geometrical_albedo/2cR1jsXm">geometrical albedo</a> and the <a href="/facts/Bond_albedo/Yn5kFpWh">Bond albedo</a> of the body. In <a href="/facts/Ephemeris/vjQCBG29">ephemeris</a> generation, the phase curve is used in conjunction with the distances from the object to the Sun and the Earth to calculate the apparent magnitude.
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Phase curve (astronomy) open-in-new

Phase curve (astronomy)