Question

Which explanation best describes why Earth observers always see the same face of the moon?

A.) The Moon’s rate of spin matches the rate at which the Moon revolves around Earth.
B.) The Moon does not rotate as it circles Earth.
C.) We tend only to observes the Moon at night, not during the day.
D.) Earth and Moon are partially gravity locked

Answer 1

I think it might be D

Step-by-step explanation:

B) would be ruled out, because if the Moon didn't rotate at all, then we would see the whole of the near side of the Moon during a full moon, half-near-half-far-side side during a half moon, and the whole of the far side of the Moon during a new moon.

C) is just foolish because sometimes we see the Moon during the day, and do we see the far side then? Short answer, no.

A) could be one of the answers, but D) sounds like the more reasonable answer for this question.

Answer 2

A

Step-by-step explanation:

Earth orbits the Sun once every 365 days and spins on its axis once every 24 hours. The Moon orbits Earth once every 27.3 days and spins on its axis once every 27.3 days. This means that although the Moon is rotating, it always keeps one face toward us. Known as “synchronous rotation,” this is why we only ever see the Moon’s nearside from Earth.