What happens when an astronaut takes off his helmet in space?

Answer

According to NASA, an astronaut could survive for half a minute without permanent damage. At least if he/she doesn’t try to hold his/her breath, as eardrum problems can occur, similar to those experienced by diving divers. In any case, the blood would not boil, man would not explode, freeze and immediately lose consciousness.

However, after about ten seconds “minor” problems such as sunburn, swelling of the skin and underlying tissue, decompression sickness,… and at some point the astronaut loses consciousness due to a lack of oxygen. The lesions pile up and after maybe one or two minutes he/she will die. When exactly is unknown.

NASA scientists believe that the astronaut will not explode and the blood will not boil due to the encompassing effect of the skin and vascular system. Despite the extremely cold space, humans will not immediately freeze, as the heat does not quickly move away from the body. Loss of consciousness only occurs once the body has used up the supply of oxygen in the blood. If the skin is exposed to direct sunlight without any protection from the harmful UV rays, severe sunburn can occur.