Outer Space
Humans can survive for several minutes in outer space without protection. They don't explode, not even a little bit. I'm so disappointed.
At first the gas in the lungs and digestive tract expands rapidly due to the pressure reduction. This can lead to ruptures, so exhale before you decide to go on a little space walk without a suit.
At the same time all water starts to vaporise. This means the moisture in eyes, mouth and nose simply boils away. This process lowers the temperature of the affected areas to near freezing due to evaporative cooling. But you won’t freeze to death (a thing almost every movie gets wrong) because even though space is very cold, it is also a near perfect vacuum and thus a very good insulator. In fact, the exposure to unfiltered UV radiation could lead to severe burns.
The water in muscles and soft tissue expands, prompting some body parts to swell to twice their size. However, this won’t be enough to break the skin and splatter someone all over. It will merely lead to a few bruises.
After a few seconds, the nitrogen dissolved in our blood starts to form bubbles, an extremely painful and potentially deadly condition known to divers as “the bends”. The same effect can be observed in a bottle of campagne that has just been opened.
A human being is conscious and aware of his or her surroundings for about 10 seconds. After that the effects of oxygen deprivation (loss of vision, impaired judgment) set in, because the reduced pressure causes the lungs to start working in reverse.
A few seconds after that a person looses consciousness, turns blue and starts convulsing. At this point a complete recovery with only minor injuries is still possible for about 90 seconds.
After these 90 seconds the blood pressure falls so low that the blood itself starts to boil and the heart stops beating.
Source: 1, 2
At first the gas in the lungs and digestive tract expands rapidly due to the pressure reduction. This can lead to ruptures, so exhale before you decide to go on a little space walk without a suit.
At the same time all water starts to vaporise. This means the moisture in eyes, mouth and nose simply boils away. This process lowers the temperature of the affected areas to near freezing due to evaporative cooling. But you won’t freeze to death (a thing almost every movie gets wrong) because even though space is very cold, it is also a near perfect vacuum and thus a very good insulator. In fact, the exposure to unfiltered UV radiation could lead to severe burns.
The water in muscles and soft tissue expands, prompting some body parts to swell to twice their size. However, this won’t be enough to break the skin and splatter someone all over. It will merely lead to a few bruises.
After a few seconds, the nitrogen dissolved in our blood starts to form bubbles, an extremely painful and potentially deadly condition known to divers as “the bends”. The same effect can be observed in a bottle of campagne that has just been opened.
A human being is conscious and aware of his or her surroundings for about 10 seconds. After that the effects of oxygen deprivation (loss of vision, impaired judgment) set in, because the reduced pressure causes the lungs to start working in reverse.
A few seconds after that a person looses consciousness, turns blue and starts convulsing. At this point a complete recovery with only minor injuries is still possible for about 90 seconds.
After these 90 seconds the blood pressure falls so low that the blood itself starts to boil and the heart stops beating.
Source: 1, 2