As I’ve said I like all things space so when someone asked me what it really would be like to be sucked out into space, I was curious as well. I think everyone has seen a science fiction film where this happens. But how realistic are those movies?
Hollywood wants to make things look good. Something like being sucked out into space scares people because space is the ultimate unknown. There’s no air, it’s cold and is probably the most harsh environment a human being would have to face. You might be surprised to know that it actually isn’t as bad as our imaginations make it out to be. And it certainly isn’t as dramatic.
Alright, so imagine that you are on a space ship, or shuttle or some other vehicle in space and the hull is breached or the airlock is released and you happen to be in the same room. Since you are some poor no-named crew member you get sucked out into space. What is the first thing you do?
Probably scream. Which might not be a bad idea. Logic might say that you should hold your breath but that would actually be a bad idea. Holding your breath may just damage your lungs. This effect is similar to what can happen if a scuba diver holds his/her breath during ascend. You risk an air embolism. This is a fancy way of saying air bubbles are released into the blood stream. If a large enough air bubble can block the blood flow to the lungs causes respiratory distress. Another possible outcome is that your lungs could tear or collapse. The fancy word for this is atelectasis.
If your lungs aren’t damaged, you still have quite a few other things to worry about and very little time to worry about them. With such low pressure on the outside of the body, hypoxia will occur. This means that the blood looses oxygen. Because when exposed to space this will happen very rapidly, you’ll only have 10 to 15 seconds of consciousness. Part of me thinks that is a blessing in disguise. Would you really want more than that amount of time to think about the fact that you are floating through space without a space suit? But it’s not just the oxygen levels in your blood that drop. Carbon dioxide levels will decrease as well. This condition is known as hypocapnia and can cause various nervous system malfunctions.
Once ambient pressure is eliminated (that’s the pressure of the air on your body), your bodily fluids will start to turn to water vapor. In other words, your blood boils. Of course put that way, it sounds a lot worse than it is. This may cause some frost to appear in the mouth or around the eyes which is probably where the idea of the body freezing came from.
There are some other minor problems as well. If you happen to be in the direct line of some UV-rays from a star… well you may get a really bad sunburn. Your eardrums may burst due to the pressure build up in the body. It will leave you deaf but won’t kill you. There may be some swelling of the skin and other tissues but if you are luckily enough to get rescued, it will likely be reversed.
It varies, but generally you have about 90 to 120 seconds to be saved. If you are lucky and get back inside within that time frame, you may live without any permanent damage. After that, your official cause of death will either be heart failure or asphyxia (medical term for suffocate). Of the two, heart failure is the most likely because you’ll probably die before asphyxia kicks in. Heart failure is caused by the pressure build up in the veins when the blood evaporated. Eventually the heart will give out, unable to function.
So as much as it pains me to say science fiction has failed us, it has. You won’t explode, or burn and you won’t instantly freeze if you find yourself out in space without a space suit. It’s not even a death sentence as there are people who have survived being exposed to a vacuum. Just hope that you have some friends near by to get you back inside…