I'm thinking about fusion engines that might be another option for space flight. Here's a great definition of nuclear fusion to get us started.
A nuclear reaction in which two small atomic nuclei fuse to form a larger one. The process releases large amounts of energy because the mass of the product is less than the mass of the fusing particles. The mass deficit corresponds to an energy release (according to Einstein's famous E=mc2 equation). Stars generate their energy by nuclear fusion. In the Sun hydrogen fuses to helium with the release of energy.
And because I'm addicted to watching science youtube videos, here's another one.
Here's one more just a little bit more nerdy. :)
While watching the videos again, I wondered why we couldn't place a small scale reactor inside cars. then we'd have fusion drive everyday!
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