Lockheed Martin has been designing a nuclear thermal propulsion (NTP) engine for cislunar operations for DARPA’s DRACO program:
But fission can do much more than simple propulsion, and that’s why the U.S. military is forking over $33.7 million for Lockheed Martin—along with Space Nuclear Power Corp (SpaceNukes) and BWX Technologies, Inc. (BWXT)—to start designing a nuclear spacecraft as part of the Joint Emergent Technology Supplying On-Orbit Nuclear (JETSON) project.
This technology demonstrator will use nuclear fission to power Stirling engines that produce between 6 kWe and 20 kWe of electricity—Lockheed Martin claims that this provides four times the power of conventional solar arrays without the need for constant sunlight. This technique comes directly from lessons learned with NASA’s Kilopower Reactor Using Stirling Technology (KRUSTY) experiment, which investigated how to provide electricity via nuclear power for future outposts on the Moon and, eventually, Mars.
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The fission engine is inert at launch and won’t turn on until the JETSON spacecraft is in a safe, non-decaying Earth orbit. Once the fission reactor creates this energy, the electricity will power Hall-effect thrusters (a kind of ion thruster that is electrified to create acceleration) that are already used on the company’s LM2100 satellites.
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This will be the first time that the U.S. military has launched a nuclear reactor into space since 1965, when the U.S. launched the SNAP-10A experimental nuclear-powered satellite (which was also the first ion thruster ever in space).
It’s about time we got some real-life atomic rockets.
Atomic rockets: The Voyagers operated just fine for over 40 years with a kind of mini plutonium reactor. Solar arrays work sort of okay until you start heading out to Mars distances from the sun.