Planet formation

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to curiouskidsus@theconversation.com. Why does the Earth spin? Sara H., age 5, New Paltz, New York A globe was the first thing I ever bought with my own money. I was maybe 5 years old, and I was really excited to take it home. As I quickly discovered, you can spin it in the direction that the earth actually spins. There’s an imaginary line between the North Pole and the South Pole. We call it the rotation axis. For the Earth, the rotation axis points toward a bright star, Polaris, which is visible on clear nights in the Northern Hemisphere. Satellite images over one day show Earth rotating on its axis. NASA/EPIC, edit by Tdadamemd If you want to know which way to spin your globe, make the...