NASA’s OSIRIS-REx spacecraft successfully touched down briefly on asteroid Bennu to retrieve samples to return to Earth. The spacecraft captured so much in its collector head that it was overflowing with the material, allowing some material to escape. NASA says that it collected well over the two-ounce mission requirement, meaning that even though some material is escaping, it still has plenty for a successful mission.
To keep any additional material from escaping from the spacecraft, NASA has announced it is moving to store the collected material currently in the Touch-And-Goal Sample Acquisition Mechanism early. The Science Mission Directorate has given the mission team the go-ahead to expedite sample storage, initially set for November 2, to begin today. The material will be removed from the collection head to the spacecraft Sample Return Capsule to minimize sample loss.
Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona, Tucson, says that the abundant material the spacecraft collected from the asteroid has made it possible to expedite the decision to store the material. His team is currently working around the clock to accelerate the stowage time to protect as much material as possible. OSIRIS-REx is different from many spacecraft in that it runs autonomously through an entire sequence with stowing of the sample material done in stages.
The team is sending preliminary commands to the spacecraft to kick off the stow sequence. The spacecraft sends telemetry data and images back to mission controllers during each step of the sequence and waits for confirmation from the team to proceed to the next step. The spacecraft is currently far enough away from Earth that it takes 18.5 minutes for signals to travel between the spacecraft and our planet. That means each step of the process has a 37-minute delay.
NASA did add a new imaging sequence to the stowage process to monitor the amount of material leaking out of the collection head. The entire stowage process will take multiple days and result in the sample being sealed in the Sample Return Capsule.