“Dad, they say Earth spins like a top. So why don’t we fly off?”
“Great question! Earth actually spins really fast. Near the equator, it’s turning at about 1,670 kilometers per hour.”
“That’s so fast, why don’t I feel it?”
“You know how a merry-go-round feels fine when it spins slowly, but when it spins really fast you feel like you’re about to get flung outward? Earth has a tiny bit of that same force too.”
“Then why don’t we fly off?”
“Gravity is pulling us down toward the ground way more strongly. Compared to that outward push from spinning, gravity’s grip is so much stronger that we just stay stuck to the ground.”
“So that outward push doesn’t exist at all?”
“It’s not zero. Actually, because of it, people near the equator weigh just a tiny bit less than people near the poles. A truly tiny difference, but it’s real.”
“Cool. But why can’t I feel that fast speed at all?”
“The ground you’re standing on, the air you breathe, even your own body, all of it is spinning together at the exact same speed as Earth. Kind of like sitting still inside a car, you don’t feel the speed even while it’s driving fast.”
“Oh, is that like how you only feel wind when you open the window?”
“Exactly like that! If you ever moved at a different speed than Earth’s spin, or suddenly stopped, you’d feel it. But since Earth, us, and the air are all turning together perfectly in sync, there’s nothing to feel.”
“Gravity holds us down, and the air and ground spin right along with us, so we feel absolutely nothing, even on this enormous merry-go-round.”
Your Turn Now
Share with someone today what you remember.
- How fast is Earth spinning at the equator?
- What’s the main reason we don’t fly off Earth?
- Why can’t we feel that fast speed at all?
(Check when ready: 1. About 1,670 kilometers per hour. 2. Gravity pulls much harder than the spin pushes outward. 3. The ground, air, and our bodies all spin together with Earth at the same speed.)
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