OSIRIS-REx has been in Bennu orbit since late 2018, giving NASA ample time to unexpectedly find the right landing zone on the rocky surface. It looks like she picked well. After the recent successful touch-and-launch operation, NASA reports that a large sample of the asteroid has now been sealed in the probe sample return container.
Earlier this month, OSIRIS-REx descended and clicked on the roof, or rather, it was supposed to be a faucet. NASA now says the sampling arm may have penetrated 19 inches (48 cm) of loose soil before the nitrogen exploded. That puff of air was supposed to blow about 60 grams of material into the sampling container. Instead, I reaped a lot.
There was a brief but frightening period earlier this week when NASA confirmed that large pebbles had hit the cover of the sample container. As a result, the asteroid particles were falling as the spacecraft moved. NASA chose to forgo the planned sample measurement over the weekend because that would have caused more material samples to be swept away. It also canceled any plans to conduct a second sampling at the Bennu reserve site. Instead, NASA has secured its impressive distances.
The most recent images from OSIRIS-REx show the sample safely sealed inside the sample capsule. This unit will eventually fall into Earth’s atmosphere, and the heat shield will protect it from returning to the atmosphere. We don’t know exactly how much Osiris Rex was taken from Benno, but we do know that it’s much more than a minimum of 60 grams. NASA estimates that Osiris Rex could contain up to a kilogram (1,000 grams or 2.2 pounds) of virgin asteroid soil in its return case. That’s huge – pre-sample return mission payloads can best be measured in milligrams. Hayabusa2’s latest mission hopes to capture 100 milligrams (tenth of a gram) of asteroid regolith when it lands in the coming months.
Bringing so much Bennu back to Earth could be a watershed moment for science. Most of the asteroid samples on Earth were burned by the atmosphere and shattered into small pieces on impact. Bennu has mostly remained unchanged since the formation of the universe, and we will have enough many teams to run a lot of tests that will undoubtedly teach us a lot about the early Solar System.
Bennu and OSIRIS-REx are currently millions of miles away, so it will take time for the probe to get home. NASA plans to break the orbit in March 2021 when Bennu and Earth are in close proximity. The sample return capsule should return to Earth in September 2023.
Now read:
