I have been following the solar sail mission with some enthusiasm. It provides a way for a 'space tug' to help deorbit space junk that does nobody any good. Whether it can be a reusable tug or we need a fleet of solar sail tugs is a design issue. But it would be a clever way to use solar energy in earth orbit to get rid of the junk. Source: LightSail 2 Mission Poised to Burn Up in Earth's Atmosphere The Planetary Society’s LightSail 2 launched in June 2019 and unfurled its 344-square-foot (32-square-meter) solar sail a month later. Just two weeks after spreading its wings, LightSail 2 gained 2 miles (3.2 kilometers) of altitude, making this experiment a success. But for the past few months, LightSail 2 has been losing altitude at an increasing rate. It is now sailing at an average altitude of about 390 miles (627 km), down from about 446 miles (718 km) at the beginning of the mission, according to the Planetary Society. Bob Wilson
