Rockets VI: Very nuclear rockets
See also parts I , II , III , IV , and V . Chemical rockets would be really nice if they were just a bit more energetic. The energy that goes into pushing the propellant out comes from the propellant itself, so there's stuff you can do to minimize the transmission of heat from the propellant to the rest of your engine. That helps you get around some of the problems of rockets where you heat up the propellant from outside. And the fact that you're still basically using heat means you don't have to suffer the efficiency losses that happen turning heat to electricity when you use an electric rocket . But what sort of reactions are there that we might cause in our propellant that are higher energy than chemical reactions? I think you've all seen the post title and know that I'm about to say "nuclear." Now I should make sure to say that unlike the other categories I've mentioned nobody is actively working...