The US military is getting serious about nuclear thermal propulsion

“Activity in cislunar space is expected to increase considerably in the coming years.”

There are many ways to get around space, but most of them are pretty slow. This is why, even when launching at an optimal time, a spacecraft leaving Earth requires about six months to reach orbit around Mars.

For decades, many rocket scientists have looked to a propulsion system powered by a nuclear reactor as the fastest practical means of getting to Mars and other places in the Solar System more quickly...