Gram-Scale ChipSat Spacecraft for Light Sailing in LEO

Cornell University’s Alpha mission is a 1U CubeSat that deploys a retroreflective free-flying light sail in LEO. Mounted to the sail, and serving as its flight computers, are four ChipSats –gram-scale spacecraft assembled onto a single palm-sized PCB. These satellites collect and downlink data on the sail’s orbital position and attitude kinematics, communicating directly with low-cost ground stations around the globe. This paper introduces the ChipSat developed specifically for the Alpha mission launching in 2025. The new femto-satellite builds on previous-generation designs with a significant revamp of the RF communications. This paper provides an overview of the as-flown ChipSat design and outlines significant test milestones that validated it for flight. Light sail integration, flight software architecture, and the ground segment are also discussed.