THE NEW SPACE RACE: Space nuclear power poised for breakthroughs — if NASA and DoD stay committed.

Space nuclear applications often fall into two primary categories: power generation and propulsion.

For power generation, radioisotope thermoelectric generators convert heat from radioactive decay into electricity. These systems are crucial for missions traveling to deep space where solar power becomes impractical.

On the propulsion side, two primary technologies are advancing:

Nuclear Thermal Propulsion (NTP): This uses a nuclear reactor to heat a propellant (typically liquid hydrogen) which is expelled through a nozzle to generate thrust. These systems offer high thrust levels similar to chemical rockets but with improved efficiency.

Nuclear Electric Propulsion (NEP): This process converts thermal energy from a nuclear reactor into electricity as a way to power electric thrusters. This approach provides lower thrust but exceptional efficiency, making it ideal for sustained acceleration on long-duration missions.

Not quite as good as a constant acceleration drive — but those are even further off than NTP or NEP.