WARNING: THIS POST IS A BIT GORY!
What would actually happen to you if you were exposed to space without a spacesuit? A common belief is that you would explode, but, in fact, this is not what would happen. Many people also think that – due to the fact that liquids boil at lower temperatures as pressure decreases – your blood would boil but this is also not the case. So, what would ensue after finding yourself in space without a suit?
The obvious problem is the lack of oxygen – you would lose consciousness after fifteen seconds due to lack of oxygen. You couldn’t even hold your breath as, because of the lack of pressure, the air would be forced out of your lungs. Also, if you tried to hold your breath, then any remaining air would quickly expand, rupturing the lungs.
As well as these dangers, the absence of pressure, meaning that the boiling point of blood would be reduced to below body temperature, would cause bubbles to form in your blood (this is also known as “the bends”, and divers can get it if they surface too quickly). This would mean that you would swell up, possibly even to twice your normal size, but you won’t explode, as your skin is extremely stretchy. Your blood would not boil, but its circulation would be impeded.
You’d probably last a few minutes after losing consciousness before you die – maximum. Of course, there’s also loads of ultraviolet radiation from the sun, which would give you horrendous sunburn, as well as other high-energy photons like X-rays and gamma rays, which would damage your DNA. This could lead to mutations that cause cancer, provided that you survive. It’s also incredibly cold, however, you wouldn’t freeze immediately, because the nonexistence of any oxygen means that heat would transmit away from the body unbelievably slowly.
So, you’d pass out, get the bends, swell up, get sunburnt, mutate, and your lungs may explode. Sounds like great fun!
I hope you learnt something from this post, even if it is slightly gruesome!