Far out cosmology: we can stop asteroids from hitting Earth (Introduction)

by David Turell , Friday, October 14, 2022, 02:14 (553 days ago) @ David Turell

The danger of incoming asteroids was noted before; problem solved:

https://www.scientificamerican.com/article/darts-smashing-success-shows-humanity-can-di...

"Humans have for the first time proven that they can change the path of a massive rock hurtling through space. NASA has announced that the spacecraft it slammed into an asteroid on 26 September succeeded in altering the space rock’s orbit around another asteroid — with better-than-expected results.

"Agency officials had estimated that the Double Asteroid Redirection Test (DART) spacecraft would ‘nudge’ the asteroid Dimorphos closer to its partner, Didymos, and cut its orbit time around that rock by 10–15 minutes. At an 11 October press conference, researchers confirmed that DART in fact cut the orbit time by around 32 minutes.

"Neither asteroid was a threat to Earth, but the agency tested the manoeuvre on them to prove that humanity could, in principle, deflect a worrisome space rock heading for the planet.

“'This is a watershed moment for planetary defence, and a watershed moment for humanity,” said NASA administrator Bill Nelson.

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"Although the orbit reduction is larger than expected, it still falls within the range of possibilities that scientists modelled. Researchers think the manouevre succeeded to the extent that it did because Dimorphos is more a loose collection of rocks than a solid chunk that would be harder to deflect. Another reason for the dramatic orbit change is that when DART hit, a lot of debris shot out from the asteroid into tails, each one thousands of kilometres long, and their recoil probably accentuated DART’s impact, researchers said at the press conference.

"For now, the results indicate that the US$330-million DART mission was a success. But defending Earth from future impacts requires a few things, researchers say: knowing the locations and properties of any dangerous space rocks, and having enough time to act. DART launched in November last year and took about 10 months to hit its target.

"If a threatening asteroid really were headed towards Earth, said Nancy Chabot, a planetary scientist and the DART coordination lead at Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, a mission would need to launch years in advance to deflect it safely. “Warning is really key here,” she said, adding that even space rocks larger than the 160-metre-wide Dimorphos might be dealt with given enough planning and time."

Comment: The methodology is proven but lots more preparation needs be done