NASA has successfully flight-tested a GPS-free autonomous navigation system that lets small spacecraft determine their position in orbit without satellite signals. Along the way, the same technology autonomously improved tracking data for more than 200 objects in low Earth orbit, the agency said Aug. 17.
The demonstration, called FALCON (Fast Autonomous Lost-in-space Catalog-based Optical Navigation), flew aboard NASA’s Starling CubeSat swarm. The swarm consists of four 6U spacecraft that have operated in low Earth orbit since launching in 2023. NASA’s Ames Research Center in California leads the Starling mission.
How It Works
FALCON doesn’t rely on GPS satellites or ground-based tracking. Instead, it uses Starling’s existing star-tracker cameras — instruments normally used to determine a spacecraft’s orientation by observing background stars.
The system, developed jointly with commercial software firm EraDrive, matched objects the cameras observed against an onboard catalog of roughly 20,000 known space objects. Those observed objects included other spacecraft and orbital debris. The catalog itself is maintained by the U.S. Department of War and made publicly available.
FALCON then compared what the cameras saw to where those catalogued objects were predicted to be, and calculated Starling’s own orbital position from the difference. NASA described the technique as a first for optical-camera navigation based on relative positioning to other objects in space.
A Byproduct With Safety Implications
In a separate set of experiments, FALCON flipped the process. Instead of using the catalog to find Starling’s position, it used Starling’s observations to improve the catalog itself.
Over a three-day period, the system autonomously refined the predicted orbits of more than 200 space objects. NASA said the resulting position estimates were more precise than the existing catalog data — and the refinement happened without any input from ground operators.
That refinement capability is what connects the navigation demonstration directly to space-traffic safety. Object-cataloging accuracy is a limiting factor in collision-avoidance planning, because operators can only maneuver around debris and other satellites as precisely as the underlying orbital data allows.
“FALCON is yet another success for the Starling demonstration mission,” said Roger Hunter, program manager for NASA’s Small Spacecraft and Distributed Systems program at Ames, in the agency’s announcement. “The results from FALCON can have far-reaching implications for on-orbit space-traffic monitoring, collision avoidance, and alternative navigation.”
Why GPS Independence Matters
GPS and other satellite-navigation signals become unreliable or unavailable outside the immediate vicinity of Earth. That limitation has become a growing constraint as NASA and commercial partners plan lunar and cislunar missions.
NASA said it plans to apply data from the FALCON flight tests toward autonomous navigation software for future lunar satellite constellations and cislunar logistics and science swarms. In those environments, ground tracking and GPS coverage cannot be assumed.
Closer to Earth, the agency noted that reducing dependence on ground networks — for both navigation and object tracking — could ease the burden on existing space-traffic-management infrastructure. That infrastructure already struggles to keep pace with a rapidly growing satellite population and the debris it generates.
Later this year, NASA plans to extend the FALCON experiment so Starling’s four spacecraft can share tracking data across the swarm. The goal is to refine their positions collectively, rather than relying on a single spacecraft’s observations.
Part of a Broader Pattern
FALCON’s debris-tracking function arrives as low Earth orbit’s traffic-management challenges continue to intensify. FODNews has previously reported on research quantifying how tight collision-avoidance margins in LEO have become, and on new federal requirements for continuous orbital data-sharing among satellite operators.
Autonomous, onboard systems like FALCON could help close gaps in that broader monitoring picture, since they refine object-tracking data without waiting on ground infrastructure. Still, NASA characterized the Aug. 17 results as an early technology demonstration rather than an operational system.
Sources
- NASA — “NASA’s Starling Mission Opens New Frontiers in Space Navigation,” Aug. 17, 2026
- SatNews — “NASA Demonstrates GPS-Free Autonomous Spacecraft Navigation System on Starling Swarm,” Aug. 17, 2026
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