TECH: SF Writers, Take Note. What does "spacing" do?

[mbarker.livejournal.com]

Original posting: Fri, 15 Apr 1994 18:35:01 JST

extracted from the "Space FAQ"

- HOW LONG CAN A HUMAN LIVE UNPROTECTED IN SPACE

- If you *don't* try to hold your breath, exposure to space for half a
- minute or so is unlikely to produce permanent injury. Holding your
- breath is likely to damage your lungs, something scuba divers have to
- watch out for when ascending, and you'll have eardrum trouble if your
- Eustachian tubes are badly plugged up, but theory predicts -- and animal
- experiments confirm -- that otherwise, exposure to vacuum causes no
- immediate injury. You do not explode. Your blood does not boil. You do
- not freeze. You do not instantly lose consciousness.

- Various minor problems (sunburn, possibly "the bends", certainly some
- [mild, reversible, painless] swelling of skin and underlying tissue)
- start after ten seconds or so. At some point you lose consciousness from
- lack of oxygen. Injuries accumulate. After perhaps one or two minutes,
- you're dying. The limits are not really known.

So your hero(ine), if they relax, exhale, and keep their wits about them, should have 30 seconds or so, at least, to handle the situation. Plenty of time for any red-blooded author to have them whip up an emergency spaceship (capable of faster-than-light travel, natchurly - and supplied with a useful variety of odds and ends for facing later crises) just using some leftover cans and other junk drifing in the vicinity! If MacGyver could do it, you can too!

(this TECH note brought to you by the truth in fiction committee in hopes of reviving the fading art of space opera - it ain't over until the last evil overlord is squelched, you know)

Re: TECH: SF Writers, Take Note. What does "spacing" do?

[mbarker.livejournal.com]

Original posting: Tue, 19 Apr 1994 18:35:02 JST

Hi, Phil

- But I th-th-thought it was s-so c-c-cold . . .

lots of people do, but - what's one of the best insulators? (hint - used for years in containers for hot and cold drinks)

[that's socratic inquest, if you're keeping score]

look at it another way. there are three ways for something to cool down - radiation, conduction, convection (actually, to acquire or lose heat energy).

Space (the BIG nothing) doesn't conduct, and without gases or liquids, there isn't loss to convection (which I always thought was really just conduction in a different phase, but we won't continue that argument right now). I suppose there is some loss to sublimation (as sweat converts to gas at low pressures) but it is tiny.

The only one that's left is radiation - which also is pretty slow (very few people glow, and even fewer shine:-)

And to answer my own question, that's why they use "space" (a vacuum) as insulation in the better grade of drink container. Nothing keeps what's inside hot or cold better than something!

If you happen to be in contact with .. oh, say the backside of Mercury or some other cold material, then you could have a problem. Of course, if you insist on sticking your hand in liquid nitrogen or some such here on earth, you could have a problem too.

From: Stan

- This is a very interesting point since I've always found
- fault with 2001 for having the astronaut without his helmet
- shoot through space to disable HAL. I thought the cold or
- something like that of deep space would kill (freeze) him
- instantly. I guess this isn't the case and I can go back
- to liking the movie.

yep. 2001 was pretty good about accuracy - Clarke insisted on it.

this has been today's science lesson (mr. wizard? no, there's a new one, and I don't remember the name...)

tomorrow we'll look at training common houseplants to eat parents! Won't that be fun!