This guy is very entertaining in the video, and what they're doing is very practical. Rocket engines sometimes get described as extreme plumbing. Big rockets t

This guy is very entertaining in the video, and what they're doing is very practical. Rocket engines sometimes get described as extreme plumbing. Big rockets that are more powerful than the simple solid rockets the video describes tend to use cryogenics like liquid oxygen (-185C/-300F) in one part of the rocket, and then at the other extreme have a combustion chamber over 1500C/2750F that will melt most metals. Rocket science is hard. For some more good reading, there's a great usenet archive of sci.space at http://yarchive.net/space/index.html http://yarchive.net/space/index.html