Half a million pieces of space junk are orbiting Earth at 18,000 miles per hour and could pose serious risks if nothing is done. Now there’s a plan to clean up the abandoned satellites and other human-made debris before they harm astronauts or the 1,200 active satellites in orbit. Last month, a team from the University of Surrey in England launched RemoveDebris, a spacecraft that will try to capture two pieces of space trash as a test using a harpoon and a net. Once , the junk will be dragged out of orbit and let go so it burns up while re-entering Earth’s atmosphere. The initiative is coming just in time, space experts say. A piece of debris damaged the International Space Station last year, and accidents in space could wreak on technology we depend on. “As space gets more crowded, we run the risk of a collision that knocks out things like GPS,” says John O’Meara, a physicist at St. Michael’s College in Vermont, “so this will help keep space safe.”