Satellite Surveillance
2025 marked the first official year of our newest citizen science effort, Satellite Surveillance, which delivered major milestones right out of the gate.
Observers tracked 840 different objects, including the Network’s first-ever observations of geostationary satellites, some of the most distant satellites from Earth. Two such targets, Shijian-25 and Shijian-21, were observed shortly after what appeared to be the first successful satellite refueling mission.
Closer to Earth, the Network pushed the limits by detecting its faintest low-Earth-orbit object yet: Saturnin-1, a tiny CubeSat just about a foot long — the smallest object ever observed by any of our citizen science programs. Observers also followed NASA’s solar sail mission ACS-3, tracking its deployment and rotation through changes in reflected light. Although NASA ultimately lost control of the spacecraft, this campaign marked a major first for the Satellites program.
To sum up a fantastic first year, the Satellites Surveillance program reeled in over 2,070 datasets from 90 observers! A special shout-out goes to Bryan Tobias, who made the most contributions of any campaign participant with an incredible 970 satellite observations in 2025.