What Would Happen To Your Body In Space Without A Suit?
If you found yourself floating in space without a suit, your prognosis would be grim. Thankfully, you'd probably pass out after about 15 seconds due to lack of oxygen. Your bodily fluids would experience ebullism—gas bubbles forming and causing the fluids to "boil"—because there would be no air pressure present to keep them in their liquid state. The ebullism would also result in tissue swelling. These are the guaranteed effects of exposing your body to the vacuum of space, but there are many possibilities, such as getting hit by solar wind or debris, that could also impact your "flight."
from Brain Stuff
Key Facts In This Video
In 1965, researchers exposed several dogs to a near-vacuum to study the effects on their bodies. (0:48)
Without the presence of air pressure, your bodily fluids would lose heat energy and boil. (1:30)
Holding your breath before being launched into space without a suit could rupture your lungs. (3:01)