What would actually happen to a human body in space without a suit?

Astrophysicist here! Great question, and yes, movies get this completely wrong. **You would NOT:** - Explode (your skin is elastic and contains pressure fine) - Instantly freeze (space is a vacuum, so heat transfer is slow) - Have your blood boil inside your veins (skin and vessels contain pressure) **What actually happens:** **0-10 seconds:** - Air rushes out of your lungs (don't try to hold your breath - it would damage your lungs) - You're conscious and could potentially still move - Saliva on your tongue starts to bubble (only exposed liquids boil) - You'd feel cold but not freeze instantly - Significant swelling as gases in your body expand **10-15 seconds:** - Oxygen deprivation causes unconsciousness - This is your survival window **15-60 seconds:** - Still unconscious but reversible if rescued - Heart is still beating - Brain damage begins around 90 seconds **1-2 minutes:** - Death from hypoxia (lack of oxygen) - Paralysis - Fluid in lungs **After death:** - Body would slowly freeze over hours (via radiation, not convection) - In direct sunlight, parts would get hot actually - Eventually mummify due to dehydration **Real incidents:** - A NASA technician in 1966 was exposed to near-vacuum in a test chamber. He lost consciousness in 14 seconds but was rescued and fully recovered. **So the answer is:** You'd have about 10-15 seconds of consciousness, then pass out from lack of oxygen. No explosion, no instant freezing. Just suffocation. Still don't recommend trying it though!