Yes, possible. I’m going to give a long answer with an amazing video to watch!
- Cold – not actually as much of an issue as you’d think as there is no air to conduct or convect heat away from you. So it’s just radiation which is a very slow way to lose heat.
- Vacuum – if you try to breathe, nothing will happen. Your diaphragm will move down but there will be no gas exchange obviously. You’ll die of hypoxia fairly soon (minutes). But momentary exposure is probably OK. However, don’t try to hold your breath. Like coming up from a deep dive underwater, any air you keep in your lungs will expand rapidly & shred your insides. So breathe out! Your ears would pop like you’ve never felt.
- Gases in your blood in superficial vessels might form bubbles and cause emphysema (ie gas in your tissues). Water in your blood will also vaporise. This might expand your subcutaneous tissues significantly and cause serious damage, although this is thought to be reversible on re-pressurisation. I don’t know how fast this would occur tbh, but again a brief exposure is probably OK. Again it is analogous to a diver ascending as gas bubbles (nitrogen) can form in the bloodstream.
- Moisture on your tongue will also boil off. Jim LeBlanc was testing spacesuits in a vacuum chamber in the 1960s. His gas line disconnected and his suit depressurised. Before he passed out only 14 seconds later, he described his tongue bubbling as his saliva boiled off. Here is the dramatic video. He was OK.
Finally, here is a wiki excerpt from the tragic Soyuz 11 mission, where all 3 astronauts died of depressurisation in space (the capsule was not big enough for them to be wearing spacesuits on re-entry):
The autopsies took place at Burdenko Military Hospital and found that the cause of death proper for the cosmonauts was hemorrhaging of the blood vessels in the brain, with lesser amounts of bleeding under their skin, in the inner ear, and in the nasal cavity, all of which occurred as exposure to a vacuum environment caused the oxygen and nitrogen in their bloodstreams to bubble and rupture vessels. Their blood was also found to contain heavy concentrations of lactic acid, a sign of extreme physiologic stress. Although they could have remained conscious for almost a minute after decompression began, less than 20 seconds would have passed before the effects of oxygen starvation made it impossible for them to function.
I watched Total Recall as a kid and for years thought that was the way you’d go. If anything on Mars it’d be even less dramatic than in space. But either way, still a horrendous way to die…though not quite as instantly lethal as most people think.
Source: MedlifeCrisis comments on A Doctor Talks About the Biology of The Expanse
