Dec 10, 2018 - Science

NASA spacecraft discovers evidence of water on the asteroid Bennu

Views of the asteroid Bennu from the spacecraft OSIRIS-REx, as the craft approached the asteroid.

Views of the asteroid Bennu from the spacecraft OSIRIS-REx. Credit: NASA/Goddard via the University of Arizona

NASA's OSIRIS-REx spacecraft, which has intercepted the near-Earth asteroid Bennu, has recently found molecular evidence of water locked deep inside the asteroid, NASA said Monday.

Why it matters: This is NASA’s first asteroid sample return mission, and analyzing Bennu could provide scientists with a trove of new information about the asteroid's composition and ultimately lead to new discoveries about how life evolved in the universe. Asteroids are time capsules of the early solar system and are believed to contain information about the origins of planets and the natural resources that enabled life to develop.

Details: Data obtained from the spacecraft’s two spectrometers show that molecules containing oxygen and hydrogen bonded together, known as hydroxyls, are present on the asteroid. Researchers involved in the project think that hydroxyls are located across the asteroid in water-containing clay minerals.

  • This revelation means that water was present at some time on Bennu’s parent body, which was a much larger asteroid, according to NASA. This confirms scientists' suspicions about this asteroid, which made it a prime target for a mission in the first place. Bennu is considered to be too small to currently host liquid water.

What's next: OSIRIS-REx will attempt to land on the asteroid to retrieve samples and return them to Earth in 2023. Such analysis could greatly improve our understanding of asteroid composition as well as prove concepts that could be used in new industries, such as space mining.

Go deeper: NASA spacecraft arrives at near-Earth asteroid Bennu

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