May 14, 2018
On May 7 and 9, the spacecraft conducted its second Sample Mass Measurement (SMM) pirouette activity. The SMM pirouette allows the mission team to measure the mass of the collected sample once it is in the TAGSAM head. Before sample collection, the spacecraft will do a number of spin maneuvers while the sample head is still empty. After sample collection, OSIRIS-REx will back away from the asteroid surface and pirouette again. The ground team will then compare the spacecraft’s mass properties for the “empty” and “full” spins to yield a basic estimate of the collected sample’s mass. The SMM maneuver this week provided the team with calibration information for the activity.