Jun 03, 2019
Several key events took place on the ground and in space this week for OSIRIS-REx.
On the ground, the mission’s Site Selection Board (SSB) met at the University of Arizona on May 30 to review candidate sample collection sites and to down-select contending sites from ~50 locations. As designed, the down-select process was based on whether each Region of Interest (ROI) met specific safety criteria. The down-select resulted in 23 candidate sites remaining viable, with several others potentially remaining viable under stricter system performance limits. The next step will be to utilize data from the Detailed Survey phase to assess the sampleability (likelihood that an ingestible sample of regolith will be collected) of each viable region, leading to the next round of site down-selection.
Team members also participated in a Technical Interchange Meeting (TIM) on May 29 to work through open items for the mission’s upcoming Reconnaissance phase, scheduled to begin in Fall 2019. Reconnaissance is the critical mission phase that will confirm that candidate sites are both safe and contain sampleable material, as well as provide the closeup imaging required to produce the features and landmarks required for autonomous navigation to the asteroid surface.
Up in space, the team successfully flew the spacecraft at the 6:00 a.m. Local Solar Time station for Detailed Survey: Equatorial Stations phase on May 30. For the Station 5 observations, MapCam, OTES and OVIRS collected data in continuous linear scans for a full rotation of Bennu. After these initial observations, the spacecraft performed two east-west zig-zag scans with OTES and OVIRS. In tandem, these observations help create a more complete global safety map, as well as a global science value map and global sampleability map. Data gathered at this station may also help determine which candidate sample sites have sufficient deliverability.
Next week marks the last week of the Detailed Survey mission phase, and OSIRIS-REx will enter its final station before beginning Orbital B.