The moon’s craters suggest Earth hasn’t erased lots of past impacts
Existing craters hint that asteroids increasingly pummeled both some 290 million years ago
![lunar map](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2019/01/011719_LG_earth-moon-crater_feat.jpg?fit=860%2C460&ssl=1)
SCARRED SURFACE The moon held on to almost all the craters it’s ever acquired in 4.5 billion years of impacts. This lunar map is surrounded by images of 111 craters wider than 10 kilometers and younger than a billion years.
Dr. A. Parker/SWRI