‘X’ marks the spot as NASA prepares for a historic asteroid mission.

NASA has selected the site on asteroid Bennu where its OSIRIS-REx spacecraft will retrieve a sample of space rock.

Scientists identified four potential sites before picking a spot dubbed “Nightingale” that is located in Bennu’s northern hemisphere.

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“After thoroughly evaluating all four candidate sites, we made our final decision based on which site has the greatest amount of fine-grained material and how easily the spacecraft can access that material while keeping the spacecraft safe,” said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona in Tucson, in a statement. “Of the four candidates, site Nightingale best meets these criteria and, ultimately, best ensures mission success.”

A second site, dubbed Osprey, has been picked as a backup for sample collection.

OSIRIS-REx, which stands for Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer, launched in September 2016 from Cape Canaveral Air Force Station. The spacecraft reached Bennu in December 2018.

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The spacecraft will use a robotic arm to grab the sample from Bennu.

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OSIRIS-Rex will make its first “touch-and-go” sample collection attempt in August 2020. The probe will depart Bennu in 2021 and is scheduled to return to Earth in September 2023, according to NASA.

The Associated Press contributed to this article. Fox News’ Jennifer Earl and Chris Ciaccia contributed to this article.

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