Space Nuclear Power

NASA recently ended the mission of the Opportunity Mars rover after it lost power because of a massive dust storm. That wouldn't have happened if the rover had been powered by a nuclear reactor, or even a radioisotope thermoelectric generator (RTG).

Although NASA abandoned plans for nuclear rockets in the 1960s, they have launched planetary probes powered by an RTG. Now they're looking at launching real reactors that could power a rocket or be used in a lunar or Martian base.

This is long overdue. Fission reactors can be built large enough to not only generate electricity, which is Kilopower’s role, but also to drive an efficient rocket engine. For propulsion, the nuclear reaction can supply heat to generate electricity for ion engines or, at higher power levels, blast tons of high-speed propellant out a rocket nozzle. A high-thrust nuclear thermal rocket can haul bigger payloads for the same propellant load or lower the trip times for missions to the moon or Mars. The U.S. flew an electricity-generating, 600-watt fission reactor, SNAP-10A, in 1965. The Soviet Union launched at least 30 small reactors into low Earth orbit to provide electricity for military radar reconnaissance satellites. But these low Earth orbit satellites suffered from failures that dumped a pair of their reactor cores in the ocean and in 1978 scattered another’s radioactive debris across Canada. NASA will have to design future reactors to survive launch accidents intact and begin operations only once they are well away from Earth.