Because of librations astronomers are able to see around the limb of the Moon and are able to view 59% of its surface from Earth. What is one cause of this?
A) The Moon is not perfectly round.
B) Earth is not perfectly round.
C) The Moon does not rotate on its axis at a steady rate.
D) The Moon has an elliptical orbit.

Question

Quizplus · Accepted Answer

The Moon's elliptical orbit causes it to move at varying speeds, allowing observers on Earth to see slightly more than half of its surface over time due to the effect known as libration.

Because of Librations Astronomers Are Able to See Around the Limb