As a field expert in astrophysics, I can provide you with a detailed explanation of what would happen if a human body were exposed to the vacuum of space. Firstly, it's important to clarify that while the human body would undergo severe and rapid physiological changes due to the lack of pressure in space, it would not simply "explode" as one might imagine from science fiction. The human body is composed mostly of water and has a certain amount of internal pressure that helps to keep it intact. When exposed to the vacuum of space, the body would indeed face a rapid loss of pressure. However, contrary to the common myth, the body would not explode. The skin is quite elastic and strong, and while the body would swell due to the expansion of gases within (such as oxygen and nitrogen coming out of solution in the blood and tissues), it would not rupture. The most immediate danger would actually be the lack of oxygen to breathe, which would lead to unconsciousness within a matter of seconds. Additionally, the eyes and the mucous membranes would be at risk due to the lack of moisture in space, but the body's fluids would not boil as is sometimes suggested. The temperature of space is extremely cold, but the lack of heat conduction means that without direct exposure to a heat source, the body would not heat up or cool down rapidly. In summary, while the human body would not explode in space, the exposure would be fatal due to the lack of oxygen and the rapid decompression effects. read more >>

Whatever you do, don't hold your breath!The vacuum of space will pull the air from your body. So if there's air left in your lungs, they will rupture. Oxygen in the rest of your body will also expand. You'll balloon up to twice your normal size, but you won't explode.read more >>