After launching on a United Launch Alliance Atlas V rocket on 8 September 2016, NASA’s OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer) spacecraft arrived on 3 December 2018 at its destination — the asteroid Bennu. Classified as a near-Earth asteroid, Bennu is small, about 0.3 miles in diameter but its makeup dates back to the beginnings of the solar system. OSIRIS-REx will study the asteroid for about two years before landing on its surface to retrieve a sample to return to Earth in 2021. Click to learn more about the mission and the launch.