Eli5, why does earth have way less craters then almost any other planet in our solar system?
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We have an atmosphere and an active geology, erosion and a biosphere.
The atmosphere prevents some craters from forming in the first place. You remember that big meteor/bolide caught on dash cams in Russia a while back? that never hit the ground. If it had landed on the moon it would have left an impact crater.
The active geology means that the ground is relatively young. Crust gets formed and destroyed all the time, mountains rise and get destroyed. Volcanoes cover the ground in a fresh layer of lava in many places.
Many of the craters on the moon are older than most of the rocks on earths. Many of the impact carters you see on the moon are from the so called late heavy bombardment 4 billion years ago.
The average age of the earth’s crust is about 2 to 2.5 billion years. some parts are much younger.
You will be hard pressed to find an impact crater that is a 4 billion years old in a piece of the earth surface that is only a few hundred million years old.
Even if an impact happened relatively recently enough for the earth’s tectonics to not yet have recycled the resulting crater, erosion happens.
Wind and water slowly erode craters away over millions of years.
Finally our planet is relatively unique in it having living things on it plants and animals can do a number on geological features given enough time.
There are plenty of craters around our planet that we don’t really recognize as such, because wind and rain and rivers and stuff growing all over them have covered them up and distorted them to such a degree that it take satellites and special sensors to even recognize them for what they are.
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