Michael Moreau, OSIRIS-REx deputy project manager, explained that leaving for Earth in May puts the mission “in the ‘sweet spot,’ when the departure maneuver will consume the least amount of the spacecraft’s onboard fuel.” Before the spacecraft completely leaves the rock it’s been studying for the past few years, though, it may do one more flyby in early April.
The OSIRIS-REx team is currently studying whether it’s feasible to do another flyby, which will give it a way to gather data on how the touch-and-go sample collection affected Bennu’s surface. It would also give the team the chance to assess the state of the spacecraft’s instruments, including its cameras and spectrometers. OSIRIS-REx is expected to deliver the samples it collected in September 2023. As it approaches Earth, the spacecraft will jettison the sample container, which will land with the help of parachutes in Utah.