NASA's OSIRIS-REx spacecraft had a mission in 2020: fly to Bennu, an asteroid about 200 million miles from earth, land briefly, collect a small sample, and return home. But its mission was thwarted, not by any Space Force situation or black hole anomaly, but by Bennu's surface, which is closer to a "plastic ball pit" than it is to a solid surface, NASA wrote in a new update.
"The spacecraft would have sunk into Bennu had it not fired its thrusters to back away immediately after it grabbed dust and rock from the asteroid’s surface," NASA wrote. "It turns out that the particles making up Bennu’s exterior are so loosely packed and lightly bound to each other that if a person were to step onto Bennu they would feel very little resistance, as if stepping into a pit of plastic balls that are popular play areas for kids."
The OSIRIS-REx tried to touch down two years ago when it sank into Bennu's surface. And now, they know why, according to two new papers published this week by the mission's researchers.
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"We expected the surface to be pretty rigid, kind of like if you touch down on a gravel pile: a little bit of dust flying away and a few particles jumping up," Dante Lauretta, a planetary scientist at the University of Arizona and principal investigator of the OSIRIS-REx, mission told Space.com. "But as we were bringing back the images after the event, we were stunned."
She said the surface was "soft and flowed away like a fluid."
I have never wanted to jump into anything more in my entire life, but that probably isn't a great idea considering that it is in space and I am not an astronaut.
We also don't know a ton about these kinds of asteroids. Patrick Michel, an OSIRIS-REx scientist and director of research at the Centre National de la Recherche Scientifique at Côte d’Azur Observatory in Nice, France told NASA that "we’re still at the beginning of understanding what these bodies are, because they behave in very counterintuitive ways." Moreover, looking back at images from the 2020 crash that left a 65-foot-wide impact crater was pretty wild, according to Lauretta.
"We saw a giant wall of debris flying away from the sample side," Lauretta said, dashing my hopes of sinking into an entire asteroid-size Chuck E. Cheese attraction. "For spacecraft operators, it was really frightening."
Despite Bennu's soft and fluffy nature, Space.com writes that it is "one of the most dangerous asteroids currently known" because if it collides with earth, it would cause a "continent-wide disruption on our planet." Thankfully, NASA estimates that the collision is pretty unlikely — 1 in 2,700 between the years 2175 and 2199, to be exact.
