On August 19, 2026, Firefly Aerospace announced an agreement with radioisotope power developer Zeno Power to integrate a radioisotope heating unit (RHU) aboard an upcoming Blue Ghost lunar lander mission.
The flight payload will demonstrate heat-generation capabilities required to keep critical spacecraft electronics operational through the extreme cold of the 14-day lunar night.
Technical Architecture and Thermal Payload Specifications
The integration will deploy Zeno Power’s novel radioisotope architecture, which utilizes Americium-241 (Am-241) as its heat-generating fuel source rather than conventional Plutonium-238 (Pu-238). The heat management payload features several operational parameters:
- Thermal Energy Output: The unit converts the decay heat of Am-241 directly into thermal energy, providing continuous passive warming to thermal control loops and battery bays during shadow periods.
- Fuel Half-Life and Operational Longevity: Am-241 possesses a 432-year half-life, enabling long-duration thermal management across multi-month or multi-year lunar surface deployments.
- SWaP-C Optimization: The compact heating unit is engineered for low Size, Weight, and Power (SWaP) consumption, eliminating the electrical draw required by conventional resistive solar heaters.
- Shielding and Containment: The payload incorporates a high-density, thermally resistant containment shell to safely encapsulate the radioisotope fuel during launch, transit, and landing loads.
Context and Commercial Cislunar Development
The selection expands upon Zeno Power’s development work under a $15 million NASA Tipping Point contract awarded to mature universal radioisotope power supplies for the Artemis program.
The payload integration builds upon Firefly’s lunar exploration architecture, following the flight operations of Blue Ghost Mission 1 and ongoing preparation for Blue Ghost Mission 2 to the lunar far side. Surviving the lunar night, where surface temperatures plunge to -208 degrees Fahrenheit (-133 degrees Celsius), represents a primary engineering hurdle for sustained commercial infrastructure on the Moon.
“Integrating Zeno Power’s radioisotope heating technology provides a critical capability for extended surface operations,” said Jason Kim, CEO of Firefly Aerospace. “Demonstrating passive thermal survival during the lunar night allows our Blue Ghost lander platform to support long-term scientific research and infrastructure operations across the cislunar environment.”
Flight Manifest Timeline
Engineering teams from Firefly Aerospace and Zeno Power are initiating structural and thermal interface testing at Firefly’s Cedar Park, Texas manufacturing facility. System qualification and payload integration will proceed ahead of launch, with the thermal demonstration unit manifest targeted for an upcoming commercial Blue Ghost mission.
