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OlympusMons94 t1_j96r48u wrote

Atmospheric composition doesn't matter. Density does some for small objects, but any rock big enough to make the large craters visible in images like this won't be stopped by an atmosphere.

The Moon provides negligible shielding. It covers only a tiny portion of the sky. Hold out your little finger at arm's length. The Moon is half as wide (that's wide, not long) in the sky as that little finger. Imagine how good a shield that tip of your little finger would be. Well, the Moon is smaller and it's not at arm's length. It's almost 400,000 km away. Ther eis a lot of room in between.

Earth is also a much bigger target with much stronger gravity compared to the Moon.

Jupiter is about as likely to send objects toward Earth as divert them away.

Weathering, erosion, and covering with water and sediment (as well as vegetation) because of our thick atmosphere and water are important.

Besides that, Earth has a lot of volcanism to resurface face cratered areas. That is also why the dark lunar maria we can see on the Moon are so lightly cratered compared to the lighter surrounding highlands. The maria are giant plains of frozen lava. (Much of the maria surfaces are still really old, though. A relate dlld point is that there were a lot more eimpacts very early in the solar system's history.)

Lastly, Earth also has active plate tectonics, which deforms craters on land, completely subducts craters on the ocean floor within a couple hundred million years, and is related to Earth's volcanic activity.

Because of geologic activity, Venus, Europa, Enceladus, Io, and Pluto all have surfaces with few large or obvious craters. Their surfaces have all been resurfaced by lava or ice within the past few hundred million years.

u/Itis_TheStranger

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Itis_TheStranger t1_j97jdbx wrote

Thank you for that reply. This is a great conversation and it's interesting to read the different information.

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