like a just-add-water human soup packet

December 5, 2022 1:38 PM

I saw this image on Instagram earlier today (direct link if insta is being screwy) and now I'm curious what WOULD actually happen?

I can't imagine the astronaut would be totally skeletonized unless maybe there were a breach in the suit? Space piranhas???

Some potential scenarios:
CO2 filters fail, astronaut passes out and dies, there's still a bit of O2 and thermo life support in the suit - maybe enough for some bacterial action & decomp? How would things be different based on amount & temp of atmosphere? the Moon vs Mars vs an Earth like planet (where I'm just picturing a bag of soup basically if the suit stays sealed)

O2 tank ruptures/runs out - I don't remember enough biology, but I think anerobic decomp puts off a bunch of methane gas? So a bit of human soup in a giant fart? Would there be enough gasses released under any scenario for the suit to go full marshmallow man or even explode? (Neat!)

The integrity of the suit itself fails - depending on the atmosphere or lack of it (assuming no outside life) I figure you'd be a relatively intact dry popsicle? Your liquids would boil off but all your solids would freeze, so our astronaut would be a bit of a mummy maybe?

At what point and under what conditions would she actually skeletonize inside her suit? (I don't want to know how long our astronaut would live for or what ills would befall her. In every case we'll just assume she passed quite peacefully. I want to know what happens to the body after it's already dead.

I would love to read as many takes on this as you've got. It's my birthday and it would be fun for me. Thank you :)


As a fun aside, while I was searching for the source image for a direct link I found the back of the book for which this was the cover, which gives us a little more dubious insight on what was intended.

posted by phunniemee to Science & Nature (6 answers total)

With the caveat that this is nowhere near my area of expertise, my first inclination would be to look towards Earth-bound analogs for human decomposition. We (well, anthropologists I guess) know under what conditions various forms of decay or lack thereof happen, so you could map those to your various scenarios. I would also hazard a guess that the human body carries enough decomposing bacteria in/on it to do a decent job of it if the conditions are right. For example:

-CO2 poisoning but suit otherwise intact - probably a warm/wet environment. Good for decomposition, I think. If it stays sealed, there's no good way to get moisture out, so you may end up with soup and the undigestables. This produces gas which would puff up the suit (no idea if it would burst, that would depend on construction, but if it did then I'd assume decomposition would more or less stop at whatever time the suit ruptured).
-O2 starvation - the mechanics might look a little different, but I think the end result would ultimately be the same. Might get some interesting acids and alcohols in the mix from the anaerobic bacteria and yeasts.
-Rupture while alive - there is some literature about what would happen to your still-living body as you're exposed to vacuum (assuming that's what's on the other side of the suit and not, like, methane). You'll desiccate pretty quickly and probably end up similar to desert mummies.

If you want a skeleton in a spacesuit, I think your best hope for that would be a rupture of the suit that allows outside environment in; that environment should be corrosive but not too corrosive (so, like, Venus might be a bad place because I think it would just dissolve the suit and your bones along with everything else). I would probably opt for an ambient pressure similar to Earth's to avoid the suit being crushed and sticking itself to the corpse. Given that the suit is still intact, though, I'm finding it hard to imagine a scenario that doesn't leave a pool of goo at the lowest point. Bring a towel.
posted by backseatpilot at 2:08 PM on December 5, 2022 [1 favorite]

Spoiler: That illustration is from the cover of Inherit the Stars, by James. P. Hogan. I read it as a teenager but I believe it was discovered that the astronaut had been there for a very, very long time and was an alien, so that may have an effect on the answer.

And now I read the rest of the question and see you've covered that. Ah well. I will leave this answer up because tomorrow is MY birthday.
posted by bondcliff at 2:16 PM on December 5, 2022 [4 favorites]

All spacesuits leak, and once the environmental controls run out (with todays spacesuits, a few hours) there is going to be a steady loss of moisture to space.

One big question will be where the astronaut died in relation to the sun. Is this a tidally locked planet that has one half always facing the sun, and one half always facing away(like Mercury) or is it a tidally locked moon to a planet, or something else? In the bits in the shade are going to freeze solid, while the bits in the sun are going to get quite hot (the moon surface varies between -300F in the shade to 250 F or so in the sun).

My guess is that hero is going to end up freeze-drying/ dehydrating pretty quickly. Too hot or too cold to end up soup.
posted by rockindata at 3:36 PM on December 5, 2022

There’s an episode of Doctor Who called “Silence in the Library” that may be of interest—it features people in spacesuits being instantaneously skeletonized by microscopic Space Piranhas. Amd it gets worse from there.
posted by ejs at 8:14 PM on December 5, 2022

Who's to say the alien didn't commit suicide by opening his suit somewhere, allowing local stuff in to decompose him?
posted by kschang at 5:45 AM on December 6, 2022

Ya in this particular case the astronaut was not only there for a crazy long time they were also in perpetual darkness in a vacuum (IE cold and very dry). Resemblance to the naturally mummified Chinchorro mummies is probably accurate.
posted by Mitheral at 6:50 AM on December 6, 2022