An artist's concept of a fission power system on the lunar surface. Image: NASA

A national strategy for the responsible and effective use of space nuclear power and propulsion (SNPP)—Space Policy Directive-6 (SPD-6)—was released by the White House on December 16 as a presidential memorandum.

Space nuclear systems include radioisotope power systems and nuclear reactors used for power, heating, or propulsion. Nuclear energy can produce more power at lower mass and volume compared to other energy sources and can shorten transit times for crewed and robotic spacecraft, thereby reducing radiation exposure in harsh space environments. SPD-6 establishes a road map for getting space nuclear systems into service and sets up high-level goals, principles, and federal agencies’ roles and responsibilities.

Three reactor developers got a boost on March 9 when they were each awarded a contract from the U.S. Department of Defense (DOD) to design a reactor that can fit inside a standard shipping container for military deployment. The DOD’s Strategic Capabilities Office (SCO), in partnership with the Department of Energy, proposes to build and demonstrate a 1–10 MWe reactor within four years that, if successful, could be widely deployed to support the DOD’s domestic and operational energy demands.