!CubeSats deployed into Earth orbit from the International Space Station. Credit: NASA/Tracy Dyson
A Miami company just switched on the first commercial nuclear power source in orbit, opening a new frontier for space energy that has long been the exclusive domain of governments.
City Labs launched its BOHR satellite (short for Betavoltaic Orbital High-Reliability) on a SpaceX Falcon 9 rideshare mission on July 7, 2026, riding alongside 80 other payloads into low-Earth orbit at an altitude of approximately 560 to 640 kilometers (350 to 400 miles). The softball-sized 1U CubeSat carries a nuclear betavoltaic battery that generates electricity from the radioactive decay of tritium, a hydrogen isotope, marking what the company calls “the world’s first commercial nuclear-powered satellite.”
“This is a historic step for commercial nuclear power in space,” said Peter Cabauy, CEO of City Labs, in a statement dated July 9, 2026. “BOHR demonstrates that safe, compact, and regulatory-approved nuclear power systems are ready for routine commercial deployment. This capability enables persistent, always-on payload operations that are not constrained by sunlight or battery life.”
The BOHR satellite uses City Labs’ experimental NanoTritium power generator in demonstration mode to supply electricity to an onboard payload, while the spacecraft itself relies on conventional solar panels for regular operations. Betavoltaic batteries like the NanoTritium are best suited for low-power applications, ranging from nanowatts to microwatts, that require a reliable, long-duration electricity source. That is far less power than a smartphone needs, let alone a large spacecraft or Moon base, but the technology fills a critical niche.
Potential use cases extend well beyond orbit. NASA has worked with City Labs to evaluate nuclear tritium power sources for a network of small sensors that could be deployed into permanently shadowed craters on the Moon to scout for resources like water ice. The U.S. Air Force and Space Force have awarded City Labs several research contracts, funding an experimental tritium AA battery for cryptographic devices and a self-powered wireless autonomous imaging sensor. City Labs says its betavoltaic systems could also power heaters for microelectronics in harsh environments, and the company is studying applications for implantable medical devices on Earth.
The BOHR mission also broke regulatory ground. It was the first commercial nuclear space mission to clear the Federal Aviation Administration’s new nuclear launch approval process, which the FAA authorized last September. That mattered because, until now, every nuclear-powered spacecraft ever launched was owned and operated by a government agency such as NASA or the U.S. military.
Tritium’s relatively benign safety profile helped clear the path. The isotope decays faster than plutonium or uranium and is far less toxic. “Tritium emits a weak form of radiation, a low-energy beta particle similar to an electron,” the Nuclear Regulatory Commission explains. “The tritium radiation does not travel very far in air and cannot penetrate the skin.” The BOHR satellite carries only a tiny amount of radioactive material, but future missions will need to launch with far more nuclear material aboard. This week’s flight served as a necessary first step.
“The BOHR mission serves as a pathfinder for future nuclear-powered spacecraft supporting both civil and national security missions,” City Labs said.
It is a long way from a 1U CubeSat to a bona fide nuclear reactor that could power a permanent Moon base or efficiently drive rockets throughout the Solar System. City Labs has demonstrated that the starting point is now commercial.