There's not much difference between now and 3.5-3.8 billion years ago, but before that there were a lot more: https://en.wikipedia.org/wiki/Late_Heavy_Bombardme

There's not much difference between now and 3.5-3.8 billion years ago, but before that there were a lot more: https://en.wikipedia.org/wiki/Late_Heavy_Bombardment https://en.wikipedia.org/wiki/Late_Heavy_Bombardment