Antares lands $160M Space Force award for orbital nuclear reactor
What's the deal? Antares, a nuclear microreactor startup, has won a $161 million Strategic Breakthrough award from the US Space ForceDealroom has a profile for this one. Try Dealroom → to advance reactors for future space missions. The grant funds a path from ground testing toward a potential flight system.
By the numbers: The award ranks in the top 1% of grant rounds for US space startups over the trailing 48 months, based on a sample of 111 deals. It follows the $470 million Series C round Antares raised in July.
What's the endgame? Antares will first demonstrate its R1-S reactor design on the ground, then integrate it with a spacecraft for flight certification. The R1-S uses heat pipes to move heat away from its nuclear core, avoiding many mechanical parts found in conventional cooling systems.
The company also plans an operational ground-to-space test of its Mark-1 reactor in 2027, running for more than six months and generating electricity through a closed Brayton cycle. Antares sees a reactor as a way to give spacecraft persistent power and greater freedom to maneuver.
Why now? The US has not operated a nuclear reactor in space since NASADealroom has a profile for this one. Try Dealroom →'s experimental SNAP-10A in 1965. Executive Order 14369 calls for reactors in space as early as 2028, with a separate initiative targeting nuclear power on the lunar surface by 2030.
Antares reached a milestone earlier this year when its Mark-0 microreactor achieved initial criticality at Idaho National LaboratoryDealroom has a profile for this one. Try Dealroom → on June 4 — a self-sustaining fission chain reaction. That made it the first private company to achieve advanced-reactor criticality under the Department of EnergyDealroom has a profile for this one. Try Dealroom →'s Reactor Pilot Program.
Chief executive officer and co-founder Jordan Bramble said the company has pursued space applications since its founding, describing the award as the point where that ambition became an official mission.
What could go wrong? The next challenge is proving a compact terrestrial reactor can survive launch and operate far from conventional power infrastructure. Flight certification remains ahead, and the technology has no modern orbital track record to build on.
The signal: Continuous electrical output could support heavier computing workloads and directed-energy systems as military operations move into more contested orbits. With demand for satellite power rising, the award signals renewed government appetite to close a six-decade gap in orbital nuclear power.
Read more: interestingengineering.com
Image credit: Antares
