A historic test flight has put Cal Poly at the center of a potential revolution in space propulsion technology. Engineering students at Cal Poly have been testing the viability of transforming a CubeSat, a tiny satellite developed on campus, into a spacecraft that uses solar energy as a source of continuous propulsion. In May, United Launch Alliance’s Atlas V rocket carried the craft, known as LightSail-1, as well as several other CubeSat vehicles, into orbit.
John Bellardo, an associate professor of computer science, and Justin Foley, a CubeSat systems engineer at Cal Poly, have been heavily involved in the university’s contributions to both LightSail and the launch.
“The deployers carrying all the CubeSats were built and integrated by Cal Poly,” Bellardo said. “In addition to the deployer, the Cal Poly team designed and built the main avionics board — the onboard computer — for LightSail.” Bellardo also developed the software responsible for listening to LightSail’s communications during the mission.
The technology centers around a thin solar sail array that fits into a breadbox-sized CubeSat, yet expands to the size of one side of a tennis court. The energy from proton radiation can be transferred to the mirror-like sails. The sails use the energy from the protons to propel the craft forward, much like a gust of wind propels a sailboat. This technology allows the craft to behave differently and more sustainably than those relying on chemical rockets, which can only give short, violent bursts of thrust.
The Planetary Society, a private nonprofit space advocacy group headed by world-famous science advocate Bill Nye, is overseeing the project. Cal Poly, along with Georgia Tech, served as a university-run ground station that monitored the craft’s progress. Communication with the craft was briefly obstructed during the mission, but LightSail ultimately sent a brief “chirp” back to the ground team at Cal Poly.
At the American Institute of Aeronautics and Astronautics/Utah State University Conference on Small Satellites this summer, LightSail was named Mission of the Year by the AIAA Small Satellite Technical Committee. Due to the success of this first test, the LightSail project is scheduled to take its next step with a flight beyond our atmosphere next year.