reply to post by tonypazzohome
Best possibility is that the vast majority of craters that exist were likely formed billions of years ago, during the height of bombardment events.
This tapered off, over time....as more and more debris got "swept up"..both by the Moon, and by Earth. Of course, Earth has weather and erosion and
plate tectonics, etc. SO, most evidence long ago erased.
The near side of the Moon clearly has experienced a period of surface lava flow activity. The far side did not.
Gravitational stresses, from the pull of the Earth? Maybe. Theories on that constantly evolve, there needs to be more exploration to get better
picture, and answers. Perhaps some of the Apollo samples gave a few hints....still, the magma activity was a LONG time ago, too...but mostly AFTER
the greatest, heaviest bombardment period. So, in a way, it was the Moon's way to "erode" the past...just not as effective as the Earth's, lacking
any atmosphere. Just different.
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And, to add another thought, forgot to mention on this:
...the moon DOES rotate on its axis right?
Yup...however, for US, at this time, is coincidence that the Moon is gravitationally "locked". Well, not "coincidence", really....probably has been
that way for millions of years, at least. And will be for many millions more. Our little "window of existence" is but a sliver of that time
scale.
BUT..a billion? Two, three billion years ago? During the heavy meteor bombardment, the Moon's period of rotation was faster...it was
NOT "tidally" locked. It orbited closer, too....but that wouldn't have affected its impacting potential with space debris.....
BTW, following OP's link to the
Daily Mail site....the first image is looking at the
south pole, mostly. You can tell by noting
the lines of latitude, and longitude, for orientation...compare it to a globe of the Earth, if you have one....( or, a globe of the Moon! Even
better!
)
edit on 20 December 2010 by weedwhacker because: (no reason given)