An American spacecraft this week successfully reached its target, the asteroid Bennu. The spacecraft OSIRIS-REx is now operating around the asteroid, about 122 million kilometers from Earth. Its goal? To bring back a sample of the ancient space rock for scientists to study. It is a process that will take years. “Relieved, proud, and anxious to start exploring!” That is what lead scientist Dante Lauretta of the University of Arizona wrote this week on Twitter. “To Bennu and back!” It is the first time the United States has tried to gather asteroid samples for return to Earth. Only Japan has successfully done so. The first step in the process has begun. OSIRIS-REx is now moving 19 kilometers above Bennu’s surface to map the asteroid. It will fly over, around and across the ancient space rock, getting as close as 7 kilometers above the surface with each flyover.