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Why is the Earth Less Cratered than the Moon?

-- Douglas | May 21, 2020

Question:

The moon is peppered with craters from impacts. Literally thousands of them.
The earth is of course very much larger and rather close to our only moon, so we have been exposed to as many as our moon. Why does earth shows very little evidence of impacts?

The geophysical actions of Earths tectonic plate movements would certainly destroy a large percentage of impact evidence, but nearly all of it?

The thought that much of the incoming bombardment would be destroyed in our atmosphere, doesn’t hold up under scrutiny. The moon has significant impact evidence of very large impacts and the vast majority of those would certainly make it through our atmosphere, even if in smaller pieces due to ballistic break-up.

Just wondering.

Thanks!

Douglas

-- Douglas

Answer:

Even though the Earth and the Moon have been bombarded by the same flux of impacting objects, the evidence of those impacts gets scrubbed-away over time by processes on the Earth which don’t exist on the Moon. On the Earth, erosion due to wind, water, and plants wear-down the impact craters. Also, plate tectonics and the processes associated with volcanism wear-away impact craters. As none of these processes exist on the Moon, the relative numbers of impact craters that we see on Earth today is much lower than those on the Moon.

-- Jeff Mangum

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