. | . |
Samples brought back from asteroid reveal 'rubble pile' had a violent past by Staff Writers Perth, Australia (SPX) Oct 19, 2017
Curtin University planetary scientists have shed some light on the evolution of asteroids, which may help prevent future collisions of an incoming 'rubble pile' asteroid with Earth. The scientists studied two incredibly small particles brought back to Earth from the asteroid Itokawa, after they were collected in 2005 from the surface of the 500 metre-wide asteroid, by the Japanese Hayabusa spacecraft. The capsule and its precious cargo returned to Earth in 2010, landing near Woomera, Australia with only about 1500 asteroid dust particles on board - most of them much smaller than the width of a human hair. The Geology-published research, Collisional history of asteroid Itokawa, used the Argon-Argon dating technique to investigate when impact crater events happened on Itokawa, offering a glimpse into the asteroid's impact history. Lead author of the study, Associate Professor Fred Jourdan from the Department of Applied Geology within the Curtin WA School of Mines, explained Itokawa was no ordinary asteroid, with fly-by pictures taken by Hayabusa prior to sampling in 2005 showing it had a peanut-like shape and resembled a rubble pile of boulders and dust more than solid rock. "In fact, analyses by Japanese scientists revealed the asteroid had a violent past. Prior to being a rubble pile, Itokawa was part of a much larger asteroid that was destroyed by a collision with another asteroid. Our job was to try to find out when that collision happened," Dr Jourdan said. Dr Jourdan explained that the analyses were not without challenges, due to the extremely small size of the particles. "Using our noble gas mass spectrometer at Curtin University, a revolutionary new machine that we customised for extra-terrestrial samples, we were able to measure tiny amounts of gas and analyse these fragments from Itokawa," Dr Jourdan said. "The impact-shocked particle indicated a small-scale collision that occurred 2.1 billion years ago, whereas the other non-shocked particle preserves a very old age, similar to the formation age of the solar system itself." According to these results and a series of models, the scientists concluded that asteroids do not always break up due to a single cataclysmic impact. Instead, they can internally fragment due to the medium-sized collisions that constantly batter large asteroids until they shatter from impact. "The final impact could be seen as 'the straw that broke the camel's back'," Dr Jourdan said. "Our results tell us that Itokawa was already broken and re-assembled as a rubble pile about 2.1 billion years ago, showing that 'rubble pile' asteroids can survive a much longer time in this state than researchers previously thought. "This is due to their cushion-like nature and the abundance of dust in between the boulders." He continued to explain these research results are not only important to understand how our solar system works, but can inform us on the best way to prevent any future collisions of an incoming 'rubble pile' asteroid with Earth. Due to the success of the team's study, they have been awarded four new particles from Itokawa, and will now look for more information to be unlocked from this asteroid. Manager of the Curtin Argon-Argon Laboratory Ms Celia Mayers said the team plans to work on samples from the Hayabusa 2 mission, which is on its way to Asteroid Ryugu, and is anticipated to bring back samples in 2020. "We also recently set up a collaboration with China that plans to bring back samples from the moon in a few years," Ms Mayers said. Dr Jourdan and his colleagues at Curtin University conducted their research at the John de Laeter Centre.
Pasadena CA (JPL) Oct 16, 2017 On Oct. 12 EDT (Oct. 11 PDT), a small asteroid designated 2012 TC4 will safely pass by Earth at a distance of approximately 26,000 miles (42,000 kilometers). This is a little over one tenth the distance to the Moon and just above the orbital altitude of communications satellites. This encounter with TC4 is being used by asteroid trackers around the world to test their ability to operate as a coo ... read more Related Links Curtin University Of Technology Asteroid and Comet Mission News, Science and Technology
|
|
The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us. |