What happens to the Earth as the moon gets farther away and will it ever go away entirely?

Since the moon is moving away from the earth farther and farther every year what effects will eventually start happening to the earth? Will it eventually be gone?

There is a physical principle called the conservation of momentum, which says that the Earth will have to slow down as the moon gets farther away. This means that the length of the day increases slightly - more hours in a day is probably all you wanted! However, the increased day length is a tiny tiny fraction of a second in our lifetimes.

The moon will never go away though. After billions of years (the precise number is hard to estimate), the moon will get to its final end state where it orbits more slowly and the Earth spins exactly as fast as the moon orbits. One side of the Earth will see the moon fully up in the sky while the other side of the Earth will never see the moon. This state is called tidally locked. By this time, the sun may have already become a red giant and disrupted or destroyed the Earth and moon entirely, though.

December 2011, Everett Schlawin (more by Everett Schlawin) (Like this Answer)

Still Curious?

Get More 'Curious?' with Our New PODCAST:

Related questions:

Is the Moon moving away from the Earth? When was this discovered?

More questions about The Moon: Previous | Next

How to ask a question:

If you have a follow-up question concerning the above subject, submit it here. If you have a question about another area of astronomy, find the topic you're interested in from the archive on our site menu, or go here for help.

URL: http://curious.astro.cornell.edu/question.php?number=773
This page has been accessed 4995 times since December 1, 2011.
Last modified: December 1, 2011 10:26:54 PM

Legal questions? See our copyright, disclaimer and privacy policy.
Ask an Astronomer is hosted by the Astronomy Department at Cornell University and is produced with PHP and MySQL.