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OSIRIS-REx candidate pattern assortment websites recognized – Astronomy Now

August 13, 2019 - Comment

4 candidate pattern assortment websites have been recognized on the asteroid Bennu. Two of these, a main and a backup, shall be chosen in December for NASA’s OSIRIS-REx spacecraft. If all goes effectively, the probe will try to gather samples later subsequent 12 months that shall be returned to Earth in 2023. As closeup photographs



4 candidate pattern assortment websites have been recognized on the asteroid Bennu. Two of these, a main and a backup, shall be chosen in December for NASA’s OSIRIS-REx spacecraft. If all goes effectively, the probe will try to gather samples later subsequent 12 months that shall be returned to Earth in 2023. As closeup photographs of the candidate websites point out, Bennu is a particularly rocky physique, making pattern assortment extra of a problem than anticipated. Picture: NASA/College of Arizona

After mapping the complete floor of the surprisingly rocky, rubble-strewn asteroid Bennu, researchers have recognized 4 potential pattern assortment websites for NASA’s OSIRIS-REx spacecraft. The group plans to spend one other 4 months evaluating the candidates earlier than deciding on a main and a backup primarily based on particle grain sizes and close by options that may function navigation landmarks throughout the spacecraft’s descent to the floor subsequent 12 months.

“We knew that Bennu would shock us, so we got here ready for no matter we’d discover,” mentioned Dante Lauretta, OSIRIS-REx principal investigator on the College of Arizona. “As with every mission of exploration, coping with the unknown requires flexibility, assets and ingenuity.”

OSIRIS-REx arrived at Bennu final December. Based mostly on Earth-based observations, scientists anticipated to search out giant “ponds” of fine-grained materials appropriate for the spacecraft’s touch-and-go pattern acquisition mechanism. For the mechanism to work correctly, collectable samples should be 2.5 centimetres (1 inch) or smaller and engineers hoped to search out boulder-free websites 50 metres (164 toes throughout to permit loads of margin for error.

Because it turned out, Bennu is way rougher than anticipated, its floor made up of numerous boulders and rock fragments in what resembles a pile of rubble. Based mostly on preliminary surveys, engineers revised their seek for acceptable pattern assortment websites, specializing in areas starting from 5 to 10 metres (16 to 33 toes) in radius.

On the identical time, they carried out an in depth reassessment of OSIRIS-REx’s capacity to exactly observe an outlined trajectory to ensure the spacecraft may, in actual fact, navigate to extra stringent concentrating on necessities.

“Though OSIRIS-REx was designed to gather a pattern from an asteroid with a beach-like space, the extraordinary in-flight efficiency thus far demonstrates that we can meet the problem that the rugged floor of Bennu presents,” mentioned Wealthy Burns, OSIRIS-REx challenge supervisor. “That extraordinary efficiency encompasses not solely the spacecraft and devices, but in addition the group who continues to satisfy each problem that Bennu throws at us.”

The 4 candidate pattern assortment websites are designated Nightingale, Kingfisher, Osprey and Sandpiper, birds native to Egypt in step with two different naming conventions: Egyptian deities and mythological birds.

OSIRIS-REx will perform detailed, high-resolution inspections of every potential pattern web site this fall, flying inside 1.29 kilometres (zero.eight miles) of Bennu’s floor to ensure they characteristic grain sizes that may be collected. Engineers additionally plan to determine floor options that can be utilized by the spacecraft’s autonomous navigation system for concentrating on.

A main and a backup web site shall be chosen in December. Passes over each of these websites shall be carried out early subsequent 12 months at even decrease altitudes. If all goes effectively, the spacecraft will try to gather samples within the second half of 2020 and return them to Earth for laboratory evaluation in September 2023.



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