Let's Climb a Ladder to Space – Will We Float or Fall? #shorts
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Imagine you have a ladder that is so tall it reaches all the way to space, high above Earth's atmosphere. What would happen if you climbed it and then just let go? Would you float right next to the ladder, like the astronauts on the space station? Would you immediately begin plummeting to the ground and fall to your death? The answer, whether you float or fall, actually depends on where you put your ladder. This is because the Earth is spinning. For example, picture a wheel.

Every part on the wheel takes the same amount of time to go around, but the further parts of the wheel have to move in a bigger circle, which means they're actually going faster. Not only can two points on the same wheel move at different speeds, they have to move at different speeds or the wheel isn't doing its job. Think about that the next time you're in your car.

The same is true for the Earth. The Earth's circumference at the equator is 40,000 kilometers. And since our planet rotates once every day, someone standing at the equator must be moving over 1,600 kilometers an hour. This is actually faster than the speed of sound, only no one at the equator notices or minds, because all the air and ground and buildings are moving at the same speed too. If you put your ladder at the equator and start climbing, it's like going farther out on the wheel, which makes you go faster.

While your feet push you up the ladder, the ladder pushes you sideways to speed you up. The higher you climb, the faster you go, until eventually you'll be high enough and fast enough that you're zipping around the Earth as fast as a satellite. If you let go here, you can simply float right alongside your ladder or push off from it and orbit on your own. But be warned: if you climb much higher than this point, you'll be going too fast to stay in orbit and you'll be slung off into space, never to return.

In fact, this is the entire principle of a space elevator which humans might one day use to transport people and cargo between the Earth's surface and space. Imagine a future with a massive tower extending tens of thousands of kilometers into the sky topped with a port for launching humans off to explore the solar system and catching voyagers when they return.

But that's also only half the answer. If you were at the North Pole, it's like being at the center of the wheel, so the Earth's rotation doesn't make you move at all, and you can't change that, no matter how high you climb. Let go of your ladder here, and you'll begin plummeting straight back down to the Earth's surface, burning up as you plunge into the atmosphere. Hopefully, you thought to pick up a magic invulnerable spacesuit from wherever you bought your ladder to space.