A common premise in science fiction, the prospect of a large asteroid hitting Earth is not fiction at all, but rather guaranteed. Extinction event asteroids occur periodically, like tides and full moons.just ask dinosaur. That’s why the National Aeronautics and Space Administration (NASA) spent so much time and money testing dual asteroid redirection. (dirt) missionwhich tested our ability to successfully deflect asteroid From colliding with the earth. The mission was a success, suggesting (seemingly) that asteroids are not as dangerous as one might think.
But what if the asteroid in question is nearly indestructible?
According to a new study published in Proceedings of the National Academy of Sciences Led by planetary scientist Fred Jordan of Curtin University in Australia (PNAS), rubble-pile asteroids are more durable (and common) than previously thought, changing scientists’ thinking about potential planetary defenses. may be changing. Rubble asteroids are, as the name suggests, a specific type of asteroid that consists of small pieces the size of boulders or rocks that have coalesced under the influence of gravity. These types of asteroids are notorious for being more diffuse than solid rock.
However, if you thought that these piles of debris were weak and easily broken due to their composition, you would be wrong.
In this study, Jourdan and his colleagues investigated the origin, composition, and durability of the Rubble Mountain asteroid, thanks to the Japanese Space Agency’s (JAXA) Hayabusa 1 probe sample return mission.
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As you may recall, JAXA collected samples from an asteroid named Itokawa in 2005, and after many setbacks, succeeded in 2010 before bringing them back to Earth. We were able to determine whether the returned Itokawa particles had previously collided in space. Through this process of scanning the particle’s surface, the researchers concluded that these asteroids are nearly indestructible, thanks to their unique “cushion”-like features.
“We usually think of asteroids as large chunks of solid rock, but not all are. “There are a lot of voids between the rocks of the Earth, and the extra voids absorb the impact,” Jordan told Salon in an email. It’s like.”
Jourdan further explained that the cushions are soft because a lot of air is trapped inside them.
“So it’s good to absorb the impact, right?” Jordan said. “Like a pile of rubble, they are good at absorbing shocks.”
This new discovery may be why the researchers found Itokawa to be so ancient – estimated at 4.2 billion years old, about the same age as our own solar system.
“I was surprised,” Jordan said of the asteroid’s age. “Most models predict that asteroids ranging in size from hundreds of meters to kilometers should survive hundreds of millions of years of atmospheric bombardment in the asteroid belt, but Itokawa is doing much more than we thought. It survived much longer, over 4.2 billion years.
Jordan said the most important implication of his research is that the Rubble Mountain asteroids are “bombproof”. It may sound like we Earthlings are doomed in terms of planetary defense, but he said, “We can use it to our advantage.”
“So what we are proposing in our research is that we should explore the possibility of detonating nuclear weapons very close to the asteroid.”
when it came darts On Mission 2022, NASA sent a 1,320-pound spacecraft to crash into a small asteroid called Demorphos and knock it out of orbit. The mission was a huge success, but Jordan said, “The problem is that the push is so small that we need to detect the asteroid very early on.”
“So if an asteroid starts to be pushed out by a kinetic shock, say, three years before it hits Earth, it doesn’t matter. Devices like DART can do that,” Jourdan said. “But what if we don’t have enough time? What if we suddenly discover that an asteroid will hit Earth within three months of her? What will we do?”
This is where Jourdan’s new research comes into play.
“So what we’re suggesting in our research is that we should explore the possibility of detonating a nuclear weapon very close to an asteroid,” Jordan said. “Why? It’s much more energetic than a small dynamic impactor like a DART.”
Jordan said the fact that the piles of rubble are so durable means that the purpose of the explosion isn’t to destroy them, but to fine-tune their trajectory so they don’t hit Earth. .
“An asteroid explosion isn’t really the way to go because all the debris rains down and causes similar devastation,” he said.