NASA delivered the NavCube3-mini payload on July 13 to Intuitive Machines for integration into Altus-1, the company’s first lunar relay satellite, marking an important milestone in the development of future lunar communications and navigation services. The lunar relays are designed to enable communications and navigation for astronauts and rovers operating at the agency’s future Moon Base.
About half the size of a shoebox and weighing just 3.5 pounds, NavCube3-mini is a compact but powerful navigation receiver designed to use signals from Earth-based GPS and Galileo Global Navigation Satellite Systems (GNSS) at lunar distances. Operating on less than 20 watts of power, roughly the same as a laptop computer, it can determine a spacecraft’s precise position far beyond Earth orbit. The compact payload builds on a series of navigation technology advancements developed at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, each extending GPS navigation to new record-breaking distances from Earth.
The payload will fly aboard Intuitive Machines’ Altus-1 lunar relay satellite, the first of a planned network of lunar relay satellites being developed under the company’s Near Space Network Services contract with NASA. The relays will provide communications and navigation support for missions operating at the Moon, including the challenging lunar South Pole region, where Artemis astronauts will land in 2028, and where direct communications with Earth can be difficult. By extending communications coverage and improving navigation services, the relay network will help realize NASA’s vision for a sustained human presence on the lunar surface.
Before being shipped to Intuitive Machines, NavCube3-mini underwent an extensive environmental and performance test campaign at NASA Goddard to verify it is ready for spaceflight. The environmental testing included vibration testing to simulate launch conditions, thermal vacuum testing in the extreme temperatures and vacuum of space, and electromagnetic compatibility testing to ensure the payload can operate reliably alongside other spacecraft systems without causing or experiencing electromagnetic interference. Performance testing was conducted before and after each environmental test using high-fidelity simulations of the GPS and Galileo signals the NavCube will encounter in lunar orbit, verifying functionality and performance throughout the testing campaign.
NavCube3-mini will serve as a key technology demonstration aboard Altus-1, validating the use of GNSS-based navigation in the lunar region and providing valuable performance data to support the development of future lunar navigation infrastructure. This technology is part of NASA’s broader strategy to develop communications and navigation services that work across both commercial providers and NASA’s networks. These capabilities are designed to support a growing lunar ecosystem that includes orbiters, landers, rovers, and, eventually, astronauts living and working on the Moon.
The delivery of NavCube3-mini marks another step toward building the communications and navigation infrastructure needed for long-term lunar exploration. Through partnerships with commercial providers like Intuitive Machines, NASA is building a more connected and capable lunar environment. As activity around the Moon continues to grow, these capabilities will enable lunar spacecraft and explorers to operate more safely, efficiently, and autonomously.
