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Tomon2 t1_j1gd73m wrote

Reply to comment by Vagabond_Grey in Russia may need to send a rescue mission to the International Space Station for 3 astronauts after a leak in their Soyuz capsule by A_Lazko

It's a good question. There's a couple of considerations and engineering challenges before you can get to a safe point of parachuting and landing.

  1. The ISS is orbiting. Just stepping out of it means you're also orbiting. What that means is that it's moving so fast in one direction, it's constantly falling and missing the earth. What you would need to do is slow down the individual's velocity in the direction of orbit - some kind of rocket or jet-pack style tech that blasts them in the opposite direction of the ISS orbit path - that way, when they're falling, they'll actually fall and "hit" earth.

  2. Reentry. Before they hit denser air, they're gonna pick up a lot of vertical speed. Considerably more than the red bull stunt guy had. As they hit the atmosphere, they're gonna make a lot of friction and heat up. So they'll need some kind of protective heat-shield until they slow and cool down to the point that a parachute is viable.

It's not impossible - but once you put together a small rocket motor and a heat shield for a couple of people, you start looking like a conventional re-entry vehicle real quick.

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ProjectDv2 t1_j1ik7tj wrote

It's not friction that creates the massive heat, it's compression. Entering the atmosphere at the speeds that stellar objects and orbiting vehicles do turns the object into essentially a large diesel piston. The air in front of the object can't move around it fast enough and instead stacks up and compresses, which causes the molecules to gain heat. By the time the object slows enough, the heat is immense.

That being said, I want people to think about what effect compression intense enough to burn up meteorites would have on a squishy human body. The cosmonauts' bodies would be utterly destroyed long before they could burn up, like stepping on a tomato.

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Vagabond_Grey t1_j1gewza wrote

What about using the damaged capsule to get the astronauts to the appropriate "bail-out zone" and jump off from that point?

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Tomon2 t1_j1gfdun wrote

Once you've made it to the "bail-out zone" - you're basically in the clear anyway. You're moving slow and cool, and you can let the capsule's parachutes do the work.

Getting them to that point is the dangerous and difficult but that we're currently worried about.

If you want to learn and play around with orbital mechanics and structures, I'd recommend playing Kerbal Space Program - or waiting til Feb and catching it's long anticipated sequel.

Lots of YouTube tutorials to help you with the mechanics, but a great way to see and feel and solve the various challenges there are with space travel.

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