OSIRIS-REx has finished stowing the bits of the carbon-rich asteroid Bennu that it snagged last Tuesday (Oct. 20), successfully locking the material into the spacecraft's return capsule, mission team members announced Thursday (Oct. 29).
And the sample appears to be substantial — far heftier than the 2.1 ounces (60 grams) the mission had set as a target, team members said. Indeed, OSIRIS-REx collected so much material on Oct. 20 that its sampling head couldn't close properly; the head's sealing mylar flap was wedged open in places by protruding Bennu pebbles.
The OSIRIS-REx team noticed that issue last week when examining photos of the head and its collected sample; flakes of escaped asteroid material drifted through the frames. To minimize the amount lost, the team decided to expedite the precise and complex stowing procedure, which was supposed to happen next week.
So, over the course of 36 hours on Tuesday and Wednesday (Oct. 27 and Oct. 28), engineers directed OSIRIS-REx to deposit the sampling head, which sat at the end of the probe's robotic arm, into the return capsule; tug on the head to make sure it was secured properly; sever connections with the robotic arm; and lock up the return capsule via the locking of two latches.