Lifeforms surviving in the vacuum of space

The answer is unknown at this time. It's a big universe, so who knows...

All I know is that it would have to survive intense cold and (some?) radiation as well. Actually, I read that during the first visit on the moon the astronauts had bacteria from the moon, sneak on the shuttle. I read that on yahoo.com, i think. However I believe they were quoting space or nasa.com.

The shuttle never went to the moon...

I seem to recall reading a NASA report about a tiny bug-like thing that didn't seem to mind vacuum or cold. But it is far from sentient.

Then what went to the moon with them? A capsule?

Apollo capsules...

The Shuttle has never left low earth orbit.

Oh ok. My mistake.

The Apollo capsules never landed, they were the mother ship pushing a lunar lander called the Eagle 1, 2, etc. With the return trip to earth, the lander was jettisoned in orbit and only the Apollo capsules returned to earth...

Arcadia Divine said:

Actually, I read that during the first visit on the moon the astronauts had bacteria from the moon, sneak on the shuttle. I read that on yahoo.com, i think. However I believe they were quoting space or nasa.com.

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Wrong. The bacteria they brought back were bacteria they took with them. NASA quarantined these astronauts upon return as a precautionary measure, out of worry about alien microbes.

The answer is yes. Not every lifeform needs to be constructed as those on Earth are. While it is highly unlikely that natural evolution would produce it by accident, it is always possible that on a planet that slowly lost its atmosphere, a suitable evolutionary track and fortunate planetary chemistry and geology could allow resistance to vacuum to come about. And of course, molecular engineering on purpose could be used to create such a being or change another into one. It would be highly unlikely short of molecular engineering, that a naturally evolved life form would be able to function for very long before dying of oxygen deprivation or going inert until exposed to oxygen again. Certainly, they would be different from anything on Earth

I could certainly believe that some kind of creatures of human level or above could live in space, though they'd require some pretty unique physiology (e.g. skin tough enough to protect against radiation and micrometeorites, energy generation from solar power, some means of motive force). However, I don't really see how they could evolve there.

Otherwise you're basically stuck with minute spores which I believe have been proven capable of living in space. From what I remember Apollo 12 recovered some hardware from the surface of the Moon which had some kind of microbes on it, though there's some question as to whether that survived the time it spent on the Moon or was accidentally spread there after the sample was returned to Earth.

Aha, here's Wikipedia on that one:

http://en.wikipedia.org/wiki/Reports_of_Streptococcus_mitis_on_the_moon

blacbird said:

Wrong. The bacteria they brought back were bacteria they took with them. NASA quarantined these astronauts upon return as a precautionary measure, out of worry about alien microbes.

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Oh, I misread it then.

I would not worry about radiation damage. Radiation isn't some magic that kills. We're constantly bathed in radiation. We're constantly suffering cellular and genetic damage from radiation. Most of it simply kills a few cells here and there, or prevents them from properly reproducing. Sometimes they do reproduce anyhow, but then you get cancer.

It's the amount of it relative to the regenerative capabilities of the lifeform. Too much and we are damaged too much for the body to handle it and the whole thing breaks down. Radiation hardening to a very limited degree has been worked on by the military (involving dietary change no less). A lifeform that had sufficient regenerative capabilities could sustain itself at much higher radiation levels than we can.

Wojciehowicz said:

I would not worry about radiation damage. Radiation isn't some magic that kills.

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A big solar flare can kill unprotected humans in minutes. It's a huge problem in spaceflight, and while Apollo got lucky (and, as far as I remember, was flown at a time when flares were considered unlikely) any long-duration spacecraft for interplanetary flights is going to have to incorporate a shielded room where the crew can sit out any such flare. Even with the Van Allen belts to protect them, astronauts on ISS sometimes have to move to the most shielded parts of the space station when radiation levels get high.

As you say, a more robust lifeform could withstand much higher radiation levels, but don't underestimate the risk.

Perfectly possible.

Oh yeah. Specifically: the water bear. It's a micro organism that can survive naked in the vacuum of space for about ten days.

Undoubtedly some life can survive in space.

Would it be sentient? Probably not. I can't say for sure (as the universe is awfully big), but sentience is probably not a "goal" of evolution and is likely quite rare and associated with some strange evolutionary events. Simply put, there's no reason for things to get smarter. Bacteria probably have us beat.

Let's assume a minimum size needed for sentience (to house a brain, or something approximate - it may not be needed, but let's pretend that something as simple as a bacteria isn't sentient and can't be.). Let's also assume a minimum complexity.

Then let's take this big, complex thing and send it out into a freezing (nearly absolute zero), radiation filled vacuum. It seems...odd to me that it could survive unless, of course, there was some kind of protection (maybe a lead exoskeleton that could self pressurize?) and it was a creature that could hybernate in a way where it didn't need air/energy/could be chilled to absolute zero and be fine).

How long it will be out also matters. Like, if we're talking about "Ken was blown out the airlock and survived for 2 seconds"...well, humans may be able to manage that. If it's "Xylon was released into space, walled himself in a protective shell, and survived for a year", OK, I might buy that. But if it's "Argos was pushed out of the space ship and just hung out there for millenia floating", I'd have a harder time seeing this as accurate...(if nothing else, bits of Argos would start evaporating off, etc.)

Then again, if you don't go into the details and handwave, it could work. I've definitely seen the concept of "sentient gigantic species roaming space for eternities, eating the dust between the planets to survive, with mini-fusion reactors within them" whatever used in published works. The science is never gone into (and I think would be rather hard to find a way in which it could work), but hey! I can suspend disbelief!

You could make a case for something being genetically engineered to survive in the vacuum.

That said, if you're looking for something that evolved to work in space, that's tricky, as has been demonstrated by several others in this thread.