If you had to jump off of the space station with with your friends, and all you could bring with you were your spacesuits, parachutes for each of you, and you had a magic device that had enough oxygen
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Orbits are all about speed, not height. To deorbit, you need to reduce your speed at the highest part of your orbit. This will lower the lowest part. You jump off the back. You would need to jump FAR harder than your legs are capable of though.
Unfortunately, the sheer speed will kill you, without shielding. As you hit the air, you are going so fast, the air can't get out of your way. You compress it ahead of you, that heats it up. It gets hot enough to melt most metals. The air will cook you, long before you get slow enough to use your parachute.
For comparison, terminal velocity (max speed you reach falling) is around 200km/h. Orbital velocity is 7km/s or around 25200km/h.
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20 bananas
Americans will truly use anything but the metric system
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You're going much too fast to hit the earth, you'll miss it and continue in orbit. To deorbit, you'll need a lot of things to throw in the other direction, like the oxygen from your magic tank. You'd need about a full rocket full of oxygen (~170 tons) to slow down, probably more because the exit velocity would be slower than a rocket.
The other issue with this scheme is you'd slow down too slowly. You'll start getting slower and lower, but you'd start to get into the atmosphere, which because you're still going so fast would cause you to not have a great time. So your magic oxygen bottle will also need a massive tube off the end of it, maybe a couple meters in diameter.
But if you had your magic infinite air tank with a huge tube off it, theoretically you could get back down to earth safely with just it, a space suit, and a parachute.
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By the time they're going fast enough, they're high enough they don't have much air to worry about. (And they do have an angle over too, not just straight up)
Missiles do go more or less go straight though the atmosphere horizontally. Most are slower than what we're taking about, but hypersonic missiles get close to rocket speeds. And they do need big heat shields to keep from melting immediately.
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If you just stepped outside of ISS you'll still be in an orbit around earth ( something something first law of motion) it would take you decades to loose enough energy to deorbit and if you survived that long without eating drinking shitting then good luck surviving the reentry.
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Minor nitpick, it's not friction, its compression. The air can't move out of your way fast enough, so you push it ahead of you, and as more air gets smooshed together, it gets hotter.
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Is that correct? I know there's still a trace of atmosphere at the altitude the ISS orbits, and they need to occasionally make a burn to regain speed lost to friction.
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Fair enough.
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At ISS altitude, it's probably not decades to decay, but a few years instead.
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Orbiting is falling to earth, but going so fast sideways that you miss, forever.
