Lunar orbit Lunar orbit In astronomy, lunar orbit (also known as a selenocentric orbit) is the orbit of an object around the Moon. As used in the space program, this refers not to the orbit of the Moon about the Earth, but to orbits by various manned or unmanned spacecraft around the Moon. The altitude at apoapsis (point farthest from the surface) for a lunar orbit is known as apolune, apocynthion, or aposelene, while the periapsis (point closest to the surface) is known as perilune, pericynthion, or periselene, from names or epithets of the moon goddess. Low lunar orbit (LLO)—orbits below altitude—are
Orbit of the Moon rotational axis of the Moon seems to rotate towards and away from Earth during one complete orbit. This is referred to as "latitudinal libration", which allows one to see almost 7° of latitude beyond the pole on the far side. Finally, because the Moon is only about 60 Earth radii away from Earth's centre of mass, an observer at the equator who observes the Moon throughout the night moves laterally by one Earth diameter. This gives rise to a "diurnal libration", which allows one to view an additional one degree's worth of lunar longitude. For the same reason, observers at