ELI5: Explain Like I'm 5

Secondary crater

Imagine you have a sandbox outside, and you decide to throw a big rock into it to make a hole. When the rock hits the ground, the sand flies everywhere and makes a big mess. Now, if you look closely, you'll notice that besides the big hole, there are also smaller holes around it, scattered all over the sand. These smaller holes are called secondary craters.

Secondary craters are created when the big rock hits the ground and sends out debris flying in all directions. Some of this debris lands back on the ground, creating new impact craters where they hit. Think of it like a game of "hot potato" – the rock is the "hot potato," and as it lands, it passes on the "hot" debris to the sand, creating new craters that didn't exist before.

Secondary craters can be found on many planets and moons in our solar system, including Earth, the Moon, Mars, and Mercury. They are important to scientists because they can provide information about the history of the planet or moon. By studying the size, shape, and distribution of these craters, scientists can learn about the impact history of the celestial body and the materials that make up its surface.