OSIRIS-REx Collects Sufficient Sample of Asteroid Bennu’s Regolith

OSIRIS-REx Collects Sufficient Sample of Asteroid Bennu’s Regolith

During the ‘Touch-And-Go’ sample collection event on October 20, 2020, NASA’s OSIRIS-REx spacecraft collected more than enough surface material (at least 60 grams) of the near-Earth asteroid Bennu to meet one of its main mission requirements, according to the mission scientists.

This series of images from OSIRIS-REx’s SamCam camera shows that the spacecraft’s sampler head is full of rocks and dust collected from the surface of Bennu. Image credit: NASA.

“Bennu continues to surprise us with great science and also throwing a few curveballs,” said Dr. Thomas Zurbuchen, NASA’s associate administrator for science at the agency’s headquarters.

“And although we may have to move more quickly to stow the sample, it’s not a bad problem to have.”

“We are so excited to see what appears to be an abundant sample that will inspire science for decades beyond this historic moment.”

Captured by the SamCam camera onboard OSIRIS-REx, new images show that the Touch-And-Go Sample Acquisition Mechanism (TAGSAM) sampler head on the spacecraft is full of regolith (rocks and dust) collected from the surface of Bennu.

The researchers also noticed that some of regolith particles appeared to be escaping slowly from the sample collector.

They suspect bits of material are passing through small gaps where a mylar flap — the collector’s ‘lid’ — is slightly wedged open by larger rocks.

The images also show that any movement to both OSIRIS-REx and the TAGSAM instrument may lead to further sample loss.

To preserve the remaining material, the mission team decided to forego the Sample Mass Measurement activity originally scheduled for October 24, and canceled a braking burn scheduled for October 23 to minimize any acceleration to the spacecraft.

The team will now focus on stowing the sample in the Sample Return Capsule (SRC), where any loose material will be kept safe during the spacecraft’s journey back to Earth.

“We are working to keep up with our own success here, and my job is to safely return as large a sample of Bennu as possible,” said OSIRIS-REx principal investigator Dr. Dante Lauretta, a researcher at the University of Arizona.

“The loss of mass is of concern to me, so I’m strongly encouraging the team to stow this precious sample as quickly as possible.”


This article is based on a press-release provided by the National Aeronautics and Space Administration.

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