NASA: OSIRIS-REx to depart Asteroid Bennuâs vicinity in May This simulations shows what the sampling likely looked like on asteroid Bennu. Source: UArizona (Source: UArizona) By KOLD News 13 Staff | January 26, 2021 at 9:05 PM MST - Updated January 26 at 9:05 PM TUCSON, Ariz. (KOLD News 13) - After collecting the sample off the surface of Asteroid Bennu, OSIRIS-REx stayed in its vicinity, but NASA says the spacecraft is just months away from beginning its journey back home. OSIRIS-REx begins that expedition on May 10, 2021, and is scheduled to deliver the collected sample to Earth in September 2023. NASA says the departure in May will allow the OSIRIS-REx team the opportunity to plan a final spacecraft flyby of Bennu. Officials say this was not part of the original mission, but that itâs a perfect opportunity to make final oberservations.