‘Rubble pile’ asteroids nearly impossible to destroy, study suggests

Curtin College-led analysis into the sturdiness and age of an historic asteroid manufactured from rocky rubble and dust, revealed vital findings that would contribute to doubtlessly saving the planet if one ever hurtled towards Earth.

The worldwide group studied three tiny dust particles collected from the floor of historic 500-meter-long rubble pile asteroid, Itokawa, returned to Earth by the Japanese Area Company’s Hayabusa 1 probe.

The research’s outcomes confirmed asteroid Itokawa, which is 2 million kilometers from Earth and across the measurement of Sydney Harbor Bridge, was arduous to destroy and proof against collision.

Lead creator Professor Fred Jourdan, Director of the Western Australian Argon Isotope Facility, a part of the John de Laeter Centre and the Faculty of Earth and Planetary Sciences at Curtin, mentioned the group additionally discovered Itokawa is nearly as previous because the solar system itself.

“In contrast to monolithic asteroids, Itokawa shouldn’t be a single lump of rock, however belongs to the rubble pile household which suggests it is fully manufactured from free boulders and rocks, with nearly half of it being empty space,” Professor Jourdan mentioned.

“The survival time of monolithic asteroids the dimensions of Itokawa is predicted to be solely a number of a whole lot of 1000’s of years within the asteroid belt.

“The large influence that destroyed Itokawa’s monolithic father or mother asteroid and fashioned Itokawa occurred at the least 4.2 billion years in the past. Such an astonishingly lengthy survival time for an asteroid the dimensions of Itokawa is attributed to the shock-absorbent nature of rubble pile materials.

“Briefly, we discovered that Itokawa is sort of a large space cushion, and really arduous to destroy.”

The Curtin-led group used two complementary strategies to investigate the three dust particles. The primary one known as Electron Backscattered Diffraction and may measure if a rock has been shocked by any meteor influence. The second methodology—argon-argon courting—is used to this point asteroid impacts.

Co-author Affiliate Professor Nick Timms, additionally from Curtin’s Faculty of Earth and Planetary Sciences, mentioned the sturdiness of rubble pile asteroids was beforehand unknown, jeopardizing the power to design protection methods in case one was hurtling towards Earth.

“We got down to reply whether or not rubble pile asteroids are proof against being shocked or whether or not they fragment on the slightest knock,” Affiliate Professor Timms mentioned.

“Now that we have now discovered they will survive within the solar system for nearly its whole historical past, they should be extra considerable within the asteroid belt than beforehand thought, so there may be extra likelihood that if an enormous asteroid is hurtling towards Earth, it will likely be a rubble pile.

“The excellent news is that we are able to additionally use this data to our benefit—if an asteroid is detected too late for a kinetic push, we are able to then doubtlessly use a extra aggressive method like utilizing the shockwave of a close-by nuclear blast to push a rubble-pile asteroid off target with out destroying it.”

Curtin College co-authors embody Affiliate Professor William Rickard, Celia Mayers, Professor Steven Reddy, Dr. David Saxey and John Curtin Distinguished Professor Phil Bland, all from the Faculty of Earth and Planetary Sciences.

Printed within the Proceedings of the Nationwide Academy of Sciences, the research is titled “Rubble pile asteroids are eternally.”