That is why the Earth has continued to spin for a very long time.Ĭurious Kids: will the universe expand forever, or contract in a big crunch? There’s no air outside our own atmosphere to slow it down either. It’s not spinning on the ground, so the ground won’t slow it down. It would take a LOT of energy to slow down the spinning Earth because it is so big. It will keep spinning unless something slows it down. That’s why they can spin for so long.īut eventually, even the air around you can cause friction and slow down a spinning top or a fidget spinner.

There’s not much friction in a fidget spinner toy. Have you ever slowed yourself down while you’re riding downhill by dragging your foot on the ground? That’s friction. Eventually it stops because the ground it is spinning on is taking energy away from the toy top through something called friction.įriction is where something rubs on or drags on an object and takes energy away. You added energy to it by starting the spin off with your hand. In theory, a spinning object will just keep spinning forever unless you add energy or take it away. But why does it keep spinning? Why the spin continues We’ve covered what made the Earth start spinning, and what made it pick up speed. So when all of the rocks in the clump of dust and gas started coming together, that made the Earth’s spin speed up. It’s just like how an ice skater or a ballerina brings in his or her arms when they want to spin faster. We end up with a planet with an iron core surrounded by rock, and maybe water and ice on the outer edges.When you make a spinning object more compact, it spins faster. Denser materials sink toward the core, and lighter materials float to the planet's surface. Rising pressure in the core then causes the core to melt. Because of the force of gravity, the planet spins faster, like an ice skater drawing in her arms to spin. When the baby planet gets massive enough, the force of gravity begins crushing it, making it denser. As a baby planet starts to grow, it gets heavier, and its gravity attracts more and more little pieces. We think that inside the disk, the gas and dust can stick together in a process called accretion. All of it - the star, the gas, the dust - spins in the same direction.Īstronomers think that our solar system looked a lot like Beta Pictoris in its early years. The star forms, spinning at the center of a flat pancake of rotating gas and dust called a protoplanetary disk.

The force of gravity causes these clouds to tug on one another as they pass, which makes them slowly rotate.Įven when one of these clouds collapses to form a star, it continues to rotate. Every star is born from a cloud of gas and dust that moves through space surrounded by other similar clouds.

Why does earth spin animation