What happens if someone takes off his space helmet in space?
Take your pick... Suffocation (there's no air in space) Severe heamorraging as the cavities and blood vessels expand and rupture. (Space is a vacumn) Freezing. (It's very cold in space) Assuming you could survive all of that, the radiation from the sun would eventually kill you. Quite quickly if there happen's to be a star (like our sun) nearby that's going through a period instability; coronal mass ejections, solar flares etc..
What would happen if someone were to take a deep breath and try to use a blowgun on the moon Would they explode?
No, but he would become dizzy. However, you could hear the sound of a blowgun because of the sompressed air that follows the expulsion of the blowgun projectile. He will also be pushed back by the air of the blowgun exiting the barrel. As soon as someone takes off the space helmet the skin will immediately boil and freeze; longer exposure will result in unconsciousness and fatal death. So yes it is possible to shoot…
What does master chief from halo look like unmasked?
Actually what happens in game when the camera pans up on the view of the pelican (when he takes off his helmet) is he actually was wearing another helmet underneath, don't ask me how to do this I've only seen it on youtube. so i know that leaves the question sorta unanswered but my guess is he looks something like Chuck Norris.