What creates an explosion? I used to think it had to do with large amounts of heat energy being released very quickly. The heat would then cause air to expand very rapidly and thus you get your explosion and shock wave. This explanation would mean that explosions couldnt really exist in space (no air or any gas). However I read an article on nuclear explosion propelled space craft, and now I'm not so sure I have explosions correct. The article said the space craft could simply harness the explosions with the use of a large parathute type thing. If this is true, whats really involved in an explosion?