A tiny CubeSat just put commercial nuclear power into orbit.
BOHR, a satellite from City Labs, launched aboard SpaceX’s Transporter-17 mission from Vandenberg Space Force Base in California. Its tritium-based NanoTritium battery will test whether a privately developed nuclear micropower source can safely operate in orbit and support future missions where solar panels and conventional batteries may not be enough.
The test is small, but the stakes are not. If the technology proves reliable, it could give commercial space companies another way to power spacecraft through darkness, extreme cold, and long-duration missions far from easy sunlight.
A CubeSat puts nuclear micropower in orbit
SpaceX’s Transporter-17 Falcon 9 rocket carried 81 payloads, including CubeSats, microsats, and orbital transfer vehicles. Space.com said the rocket began deploying payloads about 50 minutes after launch.
“This is a historic step for commercial nuclear power in space,” City Labs CEO Peter Cabauy said in a statement, according to Space.com.
BOHR, short for Betavoltaic Orbital High-Reliability, carries City Labs’ proprietary NanoTritium betavoltaic micropower source. The system uses beta particles emitted by tritium decay and converts part of their energy into electricity via a semiconductor.
It is not a nuclear reactor. It is also much smaller and weaker than the plutonium-based radioisotope thermoelectric generators NASA has used on missions such as Voyager, Curiosity, and Perseverance.
BOHR still relies on solar power for general spacecraft operations, while the nuclear payload runs as an independent proof of concept.
Commercial space gets a regulatory test case
The launch is as much a regulatory milestone as a technical one.
ZME Science reported that BOHR received FAA authorization under the US framework for launching spacecraft with nuclear systems, created by National Security Presidential Memorandum-20 in 2019.
Interesting Engineering reported that the FAA issued definitive payload authorization on September 30, 2025, after safety analysis led by City Labs and independently validated by Sandia National Laboratories.
“BOHR demonstrates that safe, compact, and regulatory-approved nuclear power systems are ready for routine commercial deployment,” Cabauy said, according to Interesting Engineering.
For commercial space companies, that approval could matter because it creates a path for more regulated nuclear micropower tests in orbit.
Potential use cases include deep-space probes, autonomous sensor networks, permanently shadowed lunar craters, and long-duration lunar surface operations.
Darkness, cold, and low-power limits
City Labs said its tritium-based systems operate at low radiation levels and are designed for safe handling, transport, and integration in commercial launch environments. The company also said tritium naturally decays into helium-3, a stable and non-radioactive isotope.
The first use cases will still be limited.
ZME Science noted that Cabauy described the technology as “very low power,” with early results expected within weeks or months.
That means tritium batteries are more likely to support sensors, heaters, and low-power electronics before they power larger spacecraft systems.
The mission adds another sign that resilient space infrastructure is becoming a commercial race, not just a government project. Lunar missions, remote sensing, defense payloads, and deep-space research all require power systems that can withstand darkness, cold, and long operating timelines.
The bigger takeaway is not that nuclear batteries will soon replace solar panels. Instead, commercial operators may now have a clearer path to test regulated nuclear power systems in orbit.
Also read: Rocket Lab’s $8 billion Iridium deal could put it in closer competition with SpaceX.