The astronauts on the ISS that are stuck and can’t parachute back to Earth… but why not?

The highest jump I could find was 39km (Stratos jump)

Is it the height from the planet? The speed of the ISS? If we wanted to design ISS escape pods, what would be required?

  • SwingingTheLamp
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    4 months ago

    It’s mostly the velocity. Orbiting a planet just means having enough kinetic energy to fall toward a planet, but continually overshoot and miss. They need some way to slow down dramatically, which is usually accomplished with rocket thrusters. If they just strapped on parachutes and jumped out, they’d orbit the Earth alongside the ISS.

  • Skunk@jlai.lu
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    4 months ago

    ISS is around 400km of altitude. There is still a little bit of atmospheric friction there so you’ll definitely end up on earth but it will take years and you’ll probably burn while passing the Kármán line at 100km.

    The good thing is that you’ll feel nothing at that moment cause you’ll be dead for a while due to no oxygen reserves.

    The only way to escape is what they do today; a re entry pod with thrusters to do an entry burn at a scheduled time (if you burn at the wrong time and place you can go “higher” towards open space instead of back to earth but you also want to aim at your landing place and not end up in the middle of manhattan or a minefield), a heat shield for passing the atmosphere and then parachutes to soften the landing.

    If you are curious about rocket science and like games, I suggest you to buy Kerbal Space Program 1, there’s tons of mods and you’ll learn while having fun.

  • usualsuspect191@lemmy.ca
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    4 months ago

    An escape pod would need some thrusters, a heat shield, and parachute at bare minimum. Thrusters to cause reentry, heat shield to bleed off most of the energy while zipping through the upper atmosphere, and parachute once sufficiently slow and low enough.

  • Thavron@lemmy.ca
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    4 months ago

    Atmospheric drag would probably light you up. Maybe someone more versed in physics could go deeper on this.