Bennu

asteroid

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Last updated

July 21, 2026

Quick Summary

Bennu is a carbon-rich asteroid approximately 490 meters (1,608 feet) in diameter. Its composition has remained largely unchanged since the early solar system, making it valuable for understanding the origins of organic compounds on Earth.1

The OSIRIS-REx mission orbited Bennu and successfully collected a sample of its surface material. This sample, returned to Earth in 2023, is the largest extraterrestrial sample collected by an American spacecraft since the Apollo Moon missions. Scientists chose Bennu due to its slow rotation, which facilitates spacecraft landings, and its rich carbon content, which may offer insights into the early solar system and the delivery of organic materials to Earth. The mission encountered challenges due to Bennu's unexpectedly rocky surface.1

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asteroid
Spacecraft exploration
…entered orbit around the asteroid Bennu on December 31, 2018. The surface of Bennu was so rocky that mission scientists had difficulty selecting a site for the spacecraft to collect a sample. The spacecraft finally touched down on the surface on October 20, 2020, and collected at least 60 grams…
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…entered orbit around the asteroid Bennu on December 31, 2018. The surface of Bennu was so rocky that mission scientists had difficulty selecting a site for the spacecraft to collect a sample. The spacecraft finally touched down on the surface on October 20, 2020, and collected at least 60 grams…
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OSIRIS-REx
spacecraft that orbited the asteroid Bennu and returned a sample of it to Earth. The roughly 250-gram (9-ounce) sample was the largest extraterrestrial sample returned to Earth since the Apollo missions to the Moon and the first asteroid sample collected by an American spacecraft.
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spacecraft that orbited the asteroid Bennu and returned a sample of it to Earth. The roughly 250-gram (9-ounce) sample was the largest extraterrestrial sample returned to Earth since the Apollo missions to the Moon and the first asteroid sample collected by an American spacecraft.
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