You probably think of asteroids as inert space rocks.
But NASA just announced that one of its spacecrafts has made a surprise discovery: "particle plumes erupting" from the surface of a large asteroid called Bennu — and while details of the discovery are still hazy, it could suggest that some asteroids are far more dynamic and poorly understood than previously believed.
The discovery of the plumes comes from an uncrewed NASA spacecraft called OSIRIS-REx, which started orbiting Bennu on Dec. 31. It's not clear from what NASA has released so far what the ejections might be comprised of, but the space agency said that while some of the plumes came out fast enough to escape Bennu entirely, others appear to get recaptured by the asteroid's gravity and come to rest again on its surface.
"The discovery of plumes is one of the biggest surprises of my scientific career," said Dante Lauretta, a principal investigator on the OSIRIS-REx mission at the University of Arizona, Tucson, in a press release. "And the rugged terrain went against all of our predictions. Bennu is already surprising us, and our exciting journey there is just getting started."
In addition to expressing surprise at the plumes, several NASA scientists praised the performance of OSIRIS-REx and its team — and expressed hope that more questions will be answered when the spacecraft returns home to Earth in 2023.
"The first three months of OSIRIS-REx’s up-close investigation of Bennu have reminded us what discovery is all about — surprises, quick thinking, and flexibility," said Lori Glaze, acting director of the Planetary Science Division at NASA Headquarters in Washington. "We study asteroids like Bennu to learn about the origin of the solar system. OSIRIS-REx’s sample will help us answer some of the biggest questions about where we come from."
READ MORE: NASA Mission Reveals Asteroid Has Big Surprises [NASA]
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