Planetary coordinate system
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A planetary coordinate system is a generalization of the geographic, geodetic, and the geocentric coordinate systems for planets other than Earth. Similar coordinate systems are defined for other soli
Chart of lunar maria with lines of longitude and latitude. The prime meridian is the centre of the near side of the Moon.
Natural satellite
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A natural satellite is, in the most common usage, an astronomical body that orbits a planet, dwarf planet, or small Solar System body. Natural satellites are colloquially referred to as moons, by anal
Size comparison of Earth and the Moon
Artist impression of Rhea's proposed rings
Jupiter family
243 ida crop