Lunar Libration
Optical libration is the wagging of the Moon perceived by Earth -bound observers caused by changes in their perspective. Moon Libration 2019 Sep 17 20:00 UTC, Lat 6.2N, Long 4.7W Moon Phase, Libration and Position Angle 2019 Sep 17 20:00 UTC Moon Libration in September 2019 "Over the course of a lunar cycle we can see more than 50% of the Moon's surface from Earth. This is because of a combination of effects which are known as "librations" of the Moon. If we view the face of the Moon over the course of its orbit in fast motion, it is as if the Moon is both nodding its head "yes" and shaking its head"no" at the same time. The lunar libration in latitude is due to the Moon's axis being slightly inclined relative to the Earth's axis. From our angle we can at one time peek over the north pole of the Moon, and then later in the lunar month we peek under the south pole. Over the entire fo