Data collected from a NASA spacecraft’s visit to thereveals future generations will want to keep a close eye on the big space rock as it makes close passes by Earth in the 22nd century.
Researchers used information from thethat spent over two years orbiting, studying and even sampling Bennu to get a better idea of its future path through the inner solar system. They found the minuscule chance the 1,700-foot-wide (518 meter) boulder will impact our planet in the future is actually slightly higher than previously thought, but still nothing to lose sleep over.
“I’m not any more concerned about Bennu than I was before,” Davide Farnocchia of NASA’s Center for Near Earth Object Studies (Cneos) told reporters on a call Wednesday. “The impact probability remains small.”
That probability is about 1 in 1,750, or 0.06%, between now and the year 2300, and we can rule out any chance of impact between today and 2135. That’s the year Bennu will come closer to Earth than the moon in September.
Farnocchia explained there’s no threat of a collision during that close pass, but before Osiris-Rex, there had been some significant uncertainty about how some effects, like our planet’s gravity, could alter Bennu’s path, perhaps making a later impact more likely.
The research team used the Osiris-Rex data to look at everything from the possible influence of the spacecraft itself — the models say it didn’t alter the asteroid’s path — to the tiny force that the sun’s heat can exert on a small body, which is called the Yarkovsky effect.
“The effect on Bennu is equivalent to the weight of three grapes constantly acting on the asteroid,” explains Steve Chesley, a senior research scientist at NASA’s Jet Propulsion Laboratory. “Tiny, yes, but significant when determining Bennu’s future impact chances over the decades and centuries to come.”
Farnocchia, Chesley and several other colleagues authored a study on Bennu’s future travels that’s published in the latest edition of the journal Icarus.
Basically, the new research allows humanity to keep kicking the can of Bennu anxiety further down the road. We can now say confidently that there’s nothing to worry about through 2135, and probably nothing to worry about until at least 2300, but you can bet that researchers in coming years will be looking closely at the asteroid’s travel plans for September of 2182.
Specifically, Sept. 24, 2182, is the most significant single date on Bennu’s itinerary because it has a .04% chance of impacting Earth that day. Another way to look at that, of course, is that there is a 99.96 chance it won’t hit us.
“We shouldn’t be worried about it very much,” Farnocchia reiterates. “We have time to keep tracking the asteroid.”
Indeed, but let’s just please make sure that a copy of the study makes it into all apocalypse-proof bunkers worldwide, in case of the unlikely event CNET and the internet don’t exist in 2182.
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