The trip home for the robotic prospector, Osiris-Rex, will take two years. It reached asteroid Bennu in 2018 and spent two years flying near and around it, before collecting rubble from the surface last autumn. The University of Arizona’s Dante Lauretta, the principal scientist, estimates the spacecraft holds between 8oz and 16oz of mostly bite-size chunks, easily exceeding the target of at least 2oz. It will be the biggest cosmic haul for the US since the Apollo moon rocks. Mission navigation has received confirmation of burn cutoff. #OSIRISREx is headed home with a souvenir of rocks and dusts from a 4.5-billion-year-old asteroid! #ToBennuAndBackpic.twitter.com/BmaK1dkPDB