Rahulparker
The eight planets in our solar system differ in lots of ways. They are different sizes. They are different distances from the sun. Some are small and rocky, and others are big and gassy. But they're all nice and round. Why is that? Why aren't they shaped like cubes, pyramids, or discs?
Planets form when material in space starts to bump and clump together. After a while it has enough stuff to have a good amount of gravity. That's the force that holds stuff together in space. When a forming planet is big enough, it starts to clear its path around the star it orbits. It uses its gravity to snag bits of space stuff.
A planet's gravity pulls equally from all sides. Gravity pulls from the center to the edges like the spokes of a bicycle wheel. This makes the overall shape of a planet a sphere, which is a three-dimensional circle.
Answers & Comments
Planets form when material in space starts to bump and clump together. After a while it has enough stuff to have a good amount of gravity. That's the force that holds stuff together in space. When a forming planet is big enough, it starts to clear its path around the star it orbits. It uses its gravity to snag bits of space stuff.
A planet's gravity pulls equally from all sides. Gravity pulls from the center to the edges like the spokes of a bicycle wheel. This makes the overall shape of a planet a sphere, which is a three-dimensional circle.