2007-01-07 09:36:01 · 7 answers · asked by Troy D 2 in Science & Mathematics ➔ Astronomy & Space
27.322 days (or 655.728 hours)
Since the Moon's orbit centers on the Earth, rather than the Sun, it would be a little confusing to think of the Moon's orbit as a "year". Instead, this cycle of the Moon orbiting the Earth is much closer to our calendar system of "months". It takes 27.322 days (or 655.728 hours) for the Moon to orbit the Earth. If that number looks familiar, it's because the orbital period of the Moon is exactly the same as its rotational period. This is the reason we can never see the far side of the Moon from Earth--it's always facing away from us.
2007-01-07 09:41:52 · answer #1 · answered by Mark E 3 · 1⤊ 0⤋
Gebobs is wrong. The moon isn't locked to the earth's rotation due to uneven mass distributions. It is locked because the center of gravity and the center of mass of the moon isn't in the same location. The precensce of the earths gravitational field on the moon causes the center of gravity of the moon to be away from the center of mass and towards earth. This causes a torque on the moon the synchronizes its rotation to the earth. Most satellites have their rotations synchronously locked to their planet for this reason. Given a long enough time. All orbiting systems will be tidally locked to each other.
2007-01-07 19:12:30 · answer #2 · answered by rokiko 1 · 0⤊ 0⤋
Agree with the above...just an explanation for why this happens: The moon's synchronous rotation is caused by an unsymmetrical distribution of mass in the Moon, which has allowed Earth's gravity to keep one lunar hemisphere permanently turned toward Earth.
Just in case someone tells you it's another thing unexplained by science and thus some kind of miracle.
2007-01-07 18:12:00 · answer #3 · answered by gebobs 6 · 0⤊ 0⤋
In respect to the background stars, the moon rotates every 27.3 days.
In respect to the sun, moon rotates in 29.5 days (so lunar day is 29.5 days). This is different from above because the moon is going around the sun at the same time.
In respect to the earth, it does not appear to rotate at all because it is rotating at the same rate as it goes around the earth (27.3 days). This is why we always see the same side of the moon.
2007-01-07 17:49:28 · answer #4 · answered by Ms. K. 3 · 0⤊ 0⤋
appr 27 and 3/4 earth days for moon to rotate on its axis.
2007-01-07 18:34:58 · answer #5 · answered by pbmaze 3 · 0⤊ 0⤋
28 days approx. The same time as it takes to orbit the earth
2007-01-07 18:28:56 · answer #6 · answered by rosie recipe 7 · 0⤊ 0⤋
28 Days, same as it's orbit around the Earth.
That's why the same side always faces us.
2007-01-07 17:38:35 · answer #7 · answered by socialdeevolution 4 · 2⤊ 1⤋