Image: OSIRIS-REx Rollout for Launch. The United Launch Alliance Atlas V rocket arrives at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The launch vehicle will boost NASA’s Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer, or OSIRIS-REx spacecraft. This will be the first U.S. mission to sample an asteroid, retrieve at least two ounces of surface material and return it to Earth for study. The asteroid, Bennu, may hold clues to the origin of the solar system and the source of water and organic molecules found on Earth.