Asteroid sample shows just what we might need to deflect a surprise killer impactor | 24CA News

Saving the Earth from an incoming planet-killing asteroid might in the future come all the way down to what we discovered from three tiny grains of fabric collected from the asteroid Itokawa.

The tiny grains, that are invisible to the bare eye, are among the many rarest scientific samples that exist.

“When you handle them there’s a chance you can lose them. As you can imagine, you’re really, really afraid this can happen,” mentioned Fred Jourdan, a professor of geochronology from Curtin University in Perth, Australia.

In 2003 the Japanese Space Agency launched the Hayabusa spacecraft on a mission to turn out to be the world’s first area probe to go to an asteroid and return samples to Earth.

The asteroid, found in 1998 and named after Japanese rocket engineer Hideo Itokawa, shaped within the asteroid belt between Mars and Jupiter, however then was ejected into its Earth-crossing orbit about two million kilometres away.

A malfunction that occurred with the probe’s pattern catcher meant that, a lot to the dismay of scientists on the bottom, it returned to Earth with just a few micrograms — about 1,500 particles of asteroid mud — as a substitute of the a number of grams they had been hoping to retrieve.

“So every single one of [the grains] is so priceless,” Jourdan informed Quirks & Quarks host Bob McDonald.

When the spacecraft visited the asteroid in 2005, one of many first issues scientists realized is that this asteroid Itokawa is what’s referred to as a “rubble pile” as a substitute of a stable chunk of rock.

“The name says it all. It’s just a pile of rubble, so there’s boulder, gravel, pebbles, dust and a lot of void spacing inside it,” Jourdan mentioned.

They kind when one asteroid within the asteroid belt slams into and destroys one other that is manufactured from stable rock — what Jourdan refers to as a “monolith” asteroid — and the fragments from the influence reassemble.

According to Jourdan, the million greenback query then grew to become: When did the influence happen that created Itokawa? 

Previously, researchers hypothesized from theoretical fashions that almost all rubble pile asteroids are doubtless just a few hundred million years outdated.

But Itokawa seems to be an exception to that rule. “The result we got is it’s at least 4.2 billion years old, so almost as old as the solar system itself which is 4.56 billion [years old],” mentioned Jourdan. 

His examine of the asteroid pattern appeared in December within the journal PNAS.

Shock resistant ‘void area’

The asteroid belt is a spot the place asteroids obliterate one another, then reform new asteroids out of the rubble, so the very fact Itokawa has been round so lengthy suggests these kind of asteroids could also be shatterproof.

“Because they can take a beating, as demonstrated by their age in the asteroid belt,” he mentioned, “they’re really resistant to shock.” 

Forty per cent of the asteroid Itokawa is void area, which explains the way it take up shocks so effectively. 

Pummeling a stable chunk of rock with a sledgehammer smashes it into items; slamming it right into a pile of rubble, however, does not have the identical impact.

“You look at the pile [after]; it looks exactly the same. Why is that? Because the energy has completely been absorbed by the void space in it,” Jourdan defined.

An even bigger push for shock shock resistant asteroids

The implications of this might assist us higher deflect an Earth-bound asteroid like this sooner or later, particularly if we get little or no discover that it is on the best way. 

In the autumn of 2022, NASA nudged a distinct rubble pile asteroid, named Dimorphos, from its orbit as a part of their Double Asteroid Redirection Test (DART), by slamming an unmanned spacecraft immediately into it.

The take a look at went effectively, largely, as a result of scientists had years to plan for this mission, and it was sufficiently far sufficient away. If the asteroid actually was on a collision course with the Earth, that delicate change in its path may be sufficient keep away from a disastrous influence if it is executed early sufficient.

Jourdan mentioned that is nice once we get plenty of discover however what if we solely have a month’s discover that an asteroid is on a crash course for our planet?

His findings recommend a rubble pile asteroid could be shock resistant sufficient to outlive us giving it an enormous push, maybe with a nuclear explosion detonated beside it. It would then be redirected with out shattering into smaller, however nonetheless doubtlessly harmful, chunks that would rain down on Earth.

These sorts of asteroids constituted of rubble appear to be extra widespread than we as soon as thought. 

Jourdan mentioned each asteroid people have despatched spacecraft to, like Ryugu, Bennu, Dimorphos and Didymos, are all rubble pile asteroids, so it is time to begin particularly getting ready for this type of risk. 

“We need to learn to defend ourselves against rubble piles, not monolith asteroids.”

Produced and written by Sonya Buyting