NASA’s OSIRIS-REx Asteroid Sampler Will Head Back to Earth on May 10
NASA’s OSIRIS-REx mission has been a smashing success so far. After reaching the asteroid Bennu at the very end of 2018, the spacecraft surveyed the surface and collected a sample. Now, NASA is making plans for OSIRIS-REx to head back to Earth with its precious cargo. According to the team, OSIRIS-REx will begin that journey on May 10th, but there are good reasons for the delay.
OSIRIS-REx collected its sample from the “Nightingale” site on Bennu several months ago. Using its collection arm, OSIRIS-REx dropped down to the carefully chosen location and blasted the asteroid with a stream of compressed nitrogen gas. The surface material ejected by the puff of air fell neatly in the probe’s sample container. Initially, NASA planned to conduct tests to make sure it had successfully scooped up some of the asteroid’s soil, but the container was visibly overflowing. Rather than tempt fate, NASA locked everything down and began planning for the return trip.
NASA says that OSIRIS-REx will leave the vicinity of Bennu on May 10th. There are a few reasons for this. First, it gives NASA the opportunity to plan one last flyby of Bennu. The team hopes to skim the surface over Nightingale to see how the spacecraft’s excavation changed the terrain. It will also give scientists a chance to assess the functionality of the probe’s onboard instruments after several years of use. The other reason for the wait is that OSIRIS-REx can use less fuel leaving Bennu’s orbit if it waits until May.
The trip back to Earth will be a long one. NASA projects OSIRIS-REx will be able to drop off the sample container on September 24, 2023. The capsule with a bit of Bennu will parachute down over the Air Force’s Utah Test and Training Range, where NASA will be waiting to retrieve it. Once on Earth, the canister will head to Johnson Space Center in Houston for analysis and processing. NASA believes it may have several kilograms of material in OSIRIS-REx, far more than the 60g design minimum. That would be enough to distribute samples of Bennu’s regolith to laboratories around the world.
So, why go to all the trouble? Collecting samples from asteroids like Bennu can help scientists piece together the history of our solar system. Unlike space rocks that have fallen into Earth’s atmosphere, a C-type asteroid like Bennu is like a time capsule of unaltered molecules from billions of years ago. That’s why missions like OSIRIS-REx and Japan’s Hayabusa2 are so important.