Jun 04, 2021
NASA’s OSIRIS-REx spacecraft is 328,000 miles, or 528,000 kilometers, away from the asteroid Bennu, having fired its engines on May 10 to initiate a return trip to Earth. The spacecraft is on track to deliver an asteroid sample to Earth on September 24, 2023. Mission engineers had planned to do a small thruster firing last week to ensure the spacecraft stays on the correct path back to Earth. But, the May 10 departure maneuver was calculated and executed so precisely, the mission team decided not to do a clean-up maneuver last week. The next possible maneuver adjustment could occur in 2022.
Mar 29, 2021
The OSIRIS-REx spacecraft continues to slowly approach asteroid Bennu – traveling approximately 6 cm/s – and is currently about 30 km from the asteroid. On Mar. 20, the spacecraft performed a third navigation maneuver to continue its journey back to Bennu for the final flyover on Apr. 7. OSIRIS-REx executed a fourth navigation maneuver on Mar. 27, which adjusted the spacecraft’s trajectory to target the location of the fifth and final maneuver. This fifth maneuver is scheduled for Apr. 4, and will place the spacecraft on the precise trajectory for the final flyby.
Mar 15, 2021
OSIRIS-REx continues operating in the Post-TAG Observation phase, as the spacecraft journeys back to Bennu for the Apr. 7 final flyover. On Mar. 6, the spacecraft successfully executed the second propulsive maneuver of 34 cm/s to adjust course as OSIRIS-REx approaches the asteroid. The next maneuver is scheduled for Mar. 20. Subsequently, OSIRIS-REx will execute two final maneuvers, which will place the spacecraft on the precise trajectory for the final flyby at about 12:30pm Local Solar Time. During this flyby, the OSIRIS-REx instrument suite will make observations of Bennu spanning the entire global surface. The science team will use these observations to assess the amount and nature of surface disruption from the sample collection event. As of Mar. 12, the spacecraft was about 155 km from Bennu and approaching the asteroid at about 24.6 cm/s. It is notable that this flyby trajectory was designed such that the failure of any maneuver would leave the spacecraft on a safe path clear of Bennu.
Feb 16, 2021
OSIRIS-REx has entered the Post-TAG Observation (PTO) phase. Currently, the spacecraft is approximately 936 km from asteroid Bennu and approaching the at about 47 cm/s. Since October’s sample collection event, the spacecraft had been slowly drifting away and ended up approximately 2,200 km from Bennu.
OSIRIS-REx executed the first of five separate navigation maneuvers on Jan. 14, which are designed to return the spacecraft to Bennu. This first maneuver acted as a braking burn and put the spacecraft on a trajectory to rendezvous with the asteroid one last time on Apr. 7.
The spacecraft will perform a second approach maneuver on Mar. 6, when it is approximately 250 km from Bennu.
After the second maneuver on Mar. 6, OSIRIS-REx will execute three subsequent maneuvers, which are required to place the spacecraft on a precise trajectory for the final flyby.
OSIRIS-REx is scheduled to depart Bennu on May 10 by firing the main engine thrusters to begin its two-year journey back to Earth. The spacecraft will deliver the samples of Bennu to the Utah Test and Training Range on Sep. 24, 2023.