US students deploy world’s first free-flying light sail in space

A student-led team at Cornell University has successfully deployed the world’s first free-flying light sail in space, named Alpha CubeSat. Deployed from the International Space Station on January 13, this light sail is also the smallest ever deployed, weighing just 0.2 pounds (100 grams) and measuring about half a meter across. Unlike previous light sails, Alpha CubeSat’s sail detaches completely from its CubeSat carrier, becoming an independent spacecraft powered solely by the momentum of sunlight photons reflecting off its retroreflective polycarbonate surface. The sail unfolds near-instantaneously via a spring-loaded latch mechanism, a significant improvement over larger sails that take minutes to hours to deploy. The mission, supported by a NASA program for student-built spacecraft, highlights the advantages of CubeSats for experimental spaceflight due to their low cost and lightweight design. Alpha CubeSat carries tiny ChipSat computers that provide solar power, computing, sensors, and communication independently of the CubeSat. After initial contact issues,