One factor that scientists were particularly concerned about is called the Yarkovsky effect, which is triggered by the constant temperature fluctuations that occur as regions of the asteroid pass in and out of daylight, gently pushing the asteroid. In addition to factors like these that affect all solar system objects, the team was also able to check the impact of two unusual characteristics of Bennu specifically: the plumes of dust that regularly shoot off the asteroid and the rock's interaction with the spacecraft itself. If the possibility of an asteroid called Bennu slamming into Earth a lifetime from now was keeping you up at night, NASA scientists think you can rest a little easier.Īs a result, scientists behind new research now say they're confident that the asteroid's total impact probability through 2300 is just 1 in 1,750. "Everyone should relax, ignore the sensationalist headlines and stories, and watch how this situation plays out," NASA's Johnson said, adding that any threat was likely to "evaporate" soon.This is the best tl dr I could make, original reduced by 81%. However such defense mechanisms look unlikely to be required for 2023 DW. The aim of SMPAG is to "have everyone on the same page and avoid what happened in the movie 'Don't Look Up'," in which "stupid stuff" happened because nations did not coordinate with each other, Moissl added. Such plans would not be considered until the probability of an impact passes one in 100, when it would get the attention of UN-endorsed bodies like the International Asteroid Warning Network and the Space Mission Planning Advisory Group (SMPAG), Moissl said. The ESA's Hera mission, scheduled to launch next year to inspect the damage DART had on Dimorphos, could even be repurposed for reconnaissance if necessary, he added. With 23 years to prepare, there is "ample time" for such a mission to be planned, Moissl said. Last year, NASA's DART spacecraft deliberately slammed into the pyramid-sized asteroid Dimorphos, significantly knocking it off course in the first such test of our planetary defenses.įarnocchia said the "DART mission gives us confidence that such a mission would be successful" against 2023 DW, if required. While the Earth is still inside that uncertainty region, the odds temporarily increase-until further observations exclude Earth and the probability drops down to zero, as is expected to happen with 2023 DW.īut what would happen in the increasingly unlikely event that the asteroid does strike Earth?ĭavide Farnocchia, a scientist at NASA's Center for Near-Earth Object Studies, said a good comparison was the Tunguska event, in which a similarly-sized asteroid is believed to have exploded in the atmosphere above a sparsely populated area in Siberia in 1908.Įven if the asteroid is heading our way, the experts emphasized that the world is no longer defenseless against such a threat. This is because new observations shrink the "uncertainty region" where the asteroid will travel to on its closest point to Earth, he said. He said it was normal for the impact odds of newly discovered asteroids to briefly rise before rapidly falling. "We tend to be a little more conservative, but it definitely appears to now have a downward trend in probability," NASA's planetary defense officer Lindley Johnson told AFP. NASA on Tuesday lowered its own odds of impact to one in 770, meaning there was a 99.87 percent chance that the asteroid will miss Earth. "No one needs to be worried about this guy." "It will go down now with every observation until it reaches zero in a couple of days at the latest," he said. However Richard Moissl, the head of the ESA's planetary defense office, told AFP on Tuesday that overnight the probability fell to one in 1,584. Late last month the asteroid was given a one in 847 chance of hitting Earth-but the odds rose to one in 432 on Sunday, according to the ESA's risk list. It swiftly shot to the top of NASA and ESA lists of asteroids that pose a danger to Earth, leading to a raft of alarming news headlines, some warning lovers to cancel their Valentine's plans on February 14, 2046. The asteroid, which is named 2023 DW and is estimated to be around the size of a 50-meter Olympic swimming pool, was first spotted by a small Chilean observatory on February 26.
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