WASHINGTON – The Defense Innovation Unit announced May 17 it selected Ultra Safe Nuclear Corp. and Avalanche Energy to develop small nuclear-powered spacecraft for in-space demonstrations planned for 2027.

DIU, a Silicon Valley-based Pentagon organization that works with commercial industries and startups, awarded both companies “other transaction” contracts to demonstrate nuclear propulsion and power technology for future DoD space missions. OT contracts, increasingly used in military space projects, are negotiated faster than traditional defense procurements. 

The selection of Ultra Safe Nuclear and Avalanche comes just seven months after DIU issued a solicitation for small nuclear-powered engines for space missions beyond Earth orbit.

Seattle-based Ultra Safe Nuclear will demonstrate a chargeable, encapsulated nuclear radioisotope battery called EmberCore. 

Avalanche Energy, a venture-backed fusion energy startup also based in Seattle, developed a handheld micro-fusion reactor called Orbitron. “Compared to other fusion concepts, Orbitron devices are promising for space applications as they may be scaled down in size and enable their use as both a propulsion and power source,” said DIU.

Ultra Safe Nuclear last year won a contract from the Idaho National Laboratory to develop a nuclear thermal propulsion reactor concept for a NASA space exploration mission. The company also is a subcontractor to General Atomics and Blue Origin in the first phase of the Demonstration Rocket for Agile Cislunar Operations (DRACO) program overseen by the Defense Advanced Research Projects Agency.

DARPA plans to launch the DRACO nuclear thermal propulsion demonstration in 2025. 

Air Force Maj. Ryan Weed, DIU’s program manager for nuclear advanced propulsion and power, said the two small spacecraft prototypes funded by DIU complement the work being done by DARPA and NASA on nuclear propulsion for larger spacecraft. 

“DIU’s program is targeted at highly maneuverable,  small spacecraft using fusion and radioisotopes,” Weed said. “Bottom line, chemical and solar-based systems won’t provide the power needed for future DoD missions.”

Nuclear technology has traditionally been government-developed and operated, Weed said, “but we have discovered a thriving ecosystem of commercial companies, including startups, innovating in space.”

Sandra Erwin writes about military space programs, policy, technology and the industry that supports this sector. She has covered the military, the Pentagon, Congress and the defense industry for nearly two decades as editor of NDIA’s National Defense...