Earth and Moon as seen by OSIRIS-REx. October 2, 2017. The purpose of OSIRIS-REx spacecraft (acronym for Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer) is to study, map and return samples for detailed analysis from asteroid 101955 Bennu, a carbon-rich hunk of rock that might contain organic materials or molecular precursors to life. It was launched on September 8, 2016, and expected return date is September 24, 2023. If successful, OSIRIS-REx will be the first NASA spacecraft to return samples from an asteroid.