What happens to an unprotected human body in space?

Answer 1

The answer is very complex, since it depends a lot on the conditions of exposure to space. Generally speaking, however, it comes down to being able to breath. A human exposed to the vacuum of space (but not in direct sunlight) will suffocate long before any other negative effects become apparent. In fact, if you read up on the deaths of the cosmonauts of Soyuz 11, you'll find that the first people to find them were not aware they were dead.

After suffocation, the next most likely problem is hypothermia or hyperthermia. If the body isn't in direct sunlight, it will slowly cool down, but the predictions say this could take a bit. In direct sunlight, the opposite is true, although it's believed the heating would be much faster. So far, however, nobody has volunteered to test either of these situations.

Simply put, if you've got to go out into space, bring a space suit. If you can't bring a whole suit, at least bring a way to breath and stay out of the sun. Do that, and you've probably got a few minutes.