Asteroid Bennu – October 21, 2020


It’s an exciting time in the realm of space exploration! Yesterday, NASA made history as its spacecraft, the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer) performed a touch-and-go (TAG) technique to collect dust and pebbles from the surface of an ancient asteroid called Bennu. The asteroid and the OSIRIS-REx spacecraft are currently more than 200 million miles from Earth! It took the spacecraft a little over four years to reach its destination.

Sampling an asteroid can provide more insight to the early solar system – the chemical fingerprints that could help us understand how life started on Earth. NASA is still waiting to confirm that enough sample has been collected (60 grams, which is equivalent to a full-size candy bar in weight) before the spacecraft makes its 2-year-long journey back to Earth, sample safely in tow. They should know these results by next week. If there’s no sample or not enough was collected, they’ll make another attempt in January.

How was the sample collected? From the NASA press release: “OSIRIS-REx fired its thrusters to nudge itself out of orbit around Bennu. It extended the shoulder, then elbow, then wrist of its 11-foot (3.35-meter) sampling arm, known as the Touch-And-Go Sample Acquisition Mechanism (TAGSAM), and transited across Bennu while descending about a half-mile (805 meters) toward the surface. After a four-hour descent, at an altitude of approximately 410 feet (125 meters), the spacecraft executed the “Checkpoint” burn, the first of two maneuvers to allow it to precisely target the sample collection site, known as “Nightingale.” ”

Check out this animation for the sampling procedure:

Congratulations to NASA and the incredible team of scientists from around the world who have patiently and diligently worked on this project for over a decade!

photo: U. Horodyskyj of a 3D printed model of Bennu