Researchers at the U.S. Defense Advanced Research Projects Agency (DARPA) suggest that military satellites powered by nuclear propulsion — propulsion methods that use some form of nuclear reaction as their primary power source — could make U.S. military satellites more maneuverable and less vulnerable to attack.

On January 14, Michael Leahy, director of DARPA’s Tactical Technology Office, discussed a new report highlighting the benefits of using nuclear thermal propulsion for U.S. military satellites at a virtual event hosted by the Air Force Association’s Mitchell Institute.

Leahy suggested that DARPA’s upcoming Demonstration Rocket for Agile Cislunar Operations (DRACO) project, featuring a spacecraft powered by a nuclear thermal propulsion system, could potentially be the first steps toward the development of nuclear propulsion systems for military satellites.

Nuclear experts suggest in the report that nuclear propulsion could prove critical for national security space systems like Global Positioning Systems (GPS) or missile-warning satellites, enabling the satellites to maneuver away from adversaries’ anti-satellite weapons.

According to the report, current U.S. satellites, which are powered by chemical propellants, are limited in terms of maneuverability, making them vulnerable to anti-satellite weapons.

Leahy explained that previous concerns over using nuclear propulsion for Earth orbiting satellites, wherein hazardous radioactive materials could potentially reenter the atmosphere, are being investigated with nuclear experts from the U.S. Department of Energy ahead of the 2025 DRACO project launch.

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