The NASA Advanced Composite Solar Sail System, launched on April 23, has experienced a minor malfunction in Earth orbit. Its mission is to test some of the most important parts of solar sailing, a new propulsion technique that NASA believes could transform the future of space travel. Solar sails work by catching photons and using their gentle but steady push, like a sailboat in the ocean — but without propellant.
The objective of ACS3 was to successfully deploy all of its four composite booms. The four booms, which carried a huge 860-square-foot sail, were successfully deployed in August. However, there is a slight bend in one of the booms, as per the information given by NASA, which was provided on October 22. The sail could stretch to its full square shape, nearly half of the size of a tennis court, and the team conducting the mission did report a deviation, however.
The space agency’s officials said it probably happens with the bends when booms and the sail have a stretched posture during its unfolding. Further analysis later also indicated the boom can recover a bit while weeks elapse, aligned in time when spacecraft tumbled slowly on-orbit as well. Its tumbling motion happened sometime after its team of ground operators would intentionally halt or deactivate attitude control for its ACS3 to stabilize based on dynamics during its unfolding sail. The system remains inert, and the spacecraft continues to rotate, but according to NASA, this poses no problem.
The team is confident that the curved boom will not have an impact on ACS3’s maneuvering in its intended exercises during the upcoming technology demonstrations. They are hopeful for solar sailing, although the concept is still at an early stage.
Japan’s Ikaros spacecraft was the first to use a solar sail as its main propellant for the Venus-bound journey, launched in May 2010. NASA tested the feasibility of using solar sails through some of its past missions. The NanoSail-D deployed its sails into Earth orbit late in 2010. The Planetary Society’s LightSail-2 also successfully deployed its sails into orbit in July 2019.
The Near-Earth Asteroid Scout cubesat (NEA Scout), launched as a rideshare mission on NASA’s Artemis 1 moon mission in November 2022, was meant to sail to an asteroid. Unfortunately, members of the mission could not establish contact with the craft post-launch.
