Can we survive in the vacuum?

We may have asked ourselves more than once what would happended to Humans if they are exposed to vacuum. Do we explode? Do we freeze? Is there any chance to get out alive?

We are not made to live in low pressure states. There is no air, which means no oxygen, no thermal regulation, no external force to resist your internal one... Dangerous. However Humans didn't though twice on and started testing with animals.

They focused on dogs and chimpanzees, and they discovered that, in general, it is possible to survive in vacuum following some rules: not being exposed for long periods of time (from some seconds to few minutes) and being slowly decompressed. You would survive for sure, but temporary or permanent drawbacks are also assured.

What are the effects on low pressure conditions?

  • Body expansion: 

Our body is constantly pushing forward the outside, trying to overcome the atmosphere weight. If you simply remove that weight away, your body will be pushing nothing, and you will get a swell shape in return.

  • Gas release: 

Our body is in average 75% water, and water properties vary with pressure. We may know water boils at 100ºC (212ºF)... In standard conditions (760 mmHg). Nevertheless vapour pressure of water in low pressure conditions drop until no threshold in absolute vacuum. This means sporadic boiling of fluids causing moisture lost, internal gas bubbles...

  • Thermal chaos: 

We control our temperature taking into account the air outside will hold part of that heat. In vacuum, heat is just lost in infrared radiation form. But this is just a long-term problem.

These are some of the visible effects. According to the lacking researches, symptoms can vary from heart failure to behaviour change, only registered on animals.

There was a Human accidental case in the early 60's, in Houston's NASA installations. A spacesuit technician had trouble with a escape from his oxigen supply. He had a loss of consciousness few seconds after the accident. Fortunatelly he had no serious harm.

Up to that day none has been exposed to that conditions (as far as we know). Human space exploration is about to begin, lets hope new suits are made for this situations never happen again.

Image Credit : Hubble Space Telescope/NASA/ESA