38
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
this post was submitted on 10 Sep 2024
38 points (93.2% liked)
Space
8476 readers
425 users here now
Share & discuss informative content on: Astrophysics, Cosmology, Space Exploration, Planetary Science and Astrobiology.
Rules
- Be respectful and inclusive.
- No harassment, hate speech, or trolling.
- Engage in constructive discussions.
- Share relevant content.
- Follow guidelines and moderators' instructions.
- Use appropriate language and tone.
- Report violations.
- Foster a continuous learning environment.
Picture of the Day
The Busy Center of the Lagoon Nebula
Related Communities
🔭 Science
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
🚀 Engineering
🌌 Art and Photography
Other Cool Links
founded 1 year ago
MODERATORS
Cooling? Just open a door.
Getting rid of heat in space is actually a serious challenge. You can only radiate it away, since there is no gas to allow convection.
This always makes me wonder: When they say space is a frozen vacuum, it wouldn't actually feel nearly as cold as it is, right? Because there's no matter to actually take that heat away from you.
The big issue is the pressure, and you'd balloon up like a blob fish out of its depth. But would it feel cold for the few instants you'd have?
no one says space is a “frozen” vacuum except movies.
Sorry, that embellishment (?) was probably mine; I guess I meant to say "really cold". And it is really cold, but it's also a very good insulator.
Actually, thinking about it, it really is freezing, isn't it? If you took some liquid water and just let it out into space, wouldn't it eventually freeze? It'd just take a really long time.
Matter not sunlit in space really is cold (and sunlit matter is baking hot, btw). It's just there is so little matter in space (vacuum and all) that getting rid of heat via conduction is virtually impossible, meaning it's insulated. So technically space is cold, also hot, and also damn well insulated.
Water not exposed to sunlight could get as low as - 260C (close to absolute zero) by radiating away all it's heat... eventually. Meanwhile water exposed to our sun in Earth orbit would be at around boiling temps, like 100-140C. Just check the Moon surface temperature readings.
The first thing to happen is that any liquids (saliva, tears, blood) will start to boil in the very low pressure, but your body won't explode like in some films. This boiling will pull heat from your body causing your nose and mouth to nearly freeze.
Another film trope is that you freeze over, but you'll often overheat first since you can't radiate your heat away quickly enough (depending on if you're in sunlight or not).
The first physiological effect will be your body parts swelling up due to lack of atmosphere.
Joseph Kittinger made a jump from over 100,000 feet, and near the peak, one of his gloves malfunctioned. His hand swelled up and became useless. But it returned to normal a while later when he was back on the ground.
That guy had one hell of an interesting life: world-record altitude, world-record jump, flying in combat and being shot down over Vietnam, being a POW, being the first person to cross the Atlantic on a balloon, and making it onto a game show.
I think Mr Musk lost a good opportunity to find out by sending a dummy instead.
Yeah but he didn’t want to be gone from spewing bullshit on twitter that long.
Anything within a sealed loop such as blood or brain fluid shouldn't be boiling. Your body is pretty good at keeping that stuff inside as long as you don't have any major cuts or something. That said, I don't think even a minor cut suffered in the vacuum could clot or scab without oxygen.
All of the air in any of your orifices would rapidly get sucked out (including from one's butt), and pretty much any liquids exposed to the resulting vacuum would boil. Negative pressure within the body means more room-temp boiling liquids, which then creates more air to get sucked out! It's a feedback loop!
A space-exposed corpse would likely end up quite dehydrated for the above reason.
TIL