Livermore Chemist Dates First Objects To Form In The Solar System

EARLY SOL

In search of leftovers from Sol's earliest days: Art by Pat Rawlings

Livermore - Sep 09, 2002
A geochemist from the Lawrence Livermore National Laboratory, teaming with researchers from the Royal Ontario Museum, the University of Hawaii and Moscow State University, has accurately dated Calcium Aluminum-rich inclusions (CAIs), the oldest objects in our solar system, to be 4.57 billion years old.

In addition, the team has determined that chondrules, another of the earliest objects in the solar system, are 2 to 3 million years younger than CAIs.

The findings, by Ian Hutcheon of LLNL, Yuri Amelin of the Royal Ontario Museum, Alexander Krot of the University of Hawaii and Alexander Ulyanov of Moscow State University, will be published in the Sept. 6, 2002 edition of Science. The article is titled "Pb Isotopic Ages of Chondrules and Ca-Al Rich Inclusions."

Using mass spectrometers to study CAIs and chondrules found in chondritic meteorites, the team was able to determine the ages of the objects by measuring the decay of uranium 238, which is found in both objects and decays into lead. Using an ion microprobe, Hutcheon dated CAIs and chondrules by detecting the decay of aluminum 26 -- also found in both objects -- into magnesium 26.

By comparing the lead and magnesium isotope contents in the CAIs and chondrules, the team determined how old the objects are. Aluminum 26 decays much faster than uranium, and these measurements enabled the team to determine the small difference in age between CAIs and chondrules with unprecedented precision.

"This is the first piece of evidence proving that CAIs are 2 to 3 million years older than chondrules," Hutcheon said. "We were able to make this conclusion based on our measurements."

CAIs and chondrules are millimeter-size objects found in primitive meteorites. They formed when dusty regions of the solar nebula were heated to very high temperatures. The dust melted and then crystallized, forming first CAIs and then chondrules. Larger objects, like asteroids and planets, took longer to form and are about 10 to 50 million years younger than the CAIs and chondrules.

"All these objects didn't just form in a snap," Hutcheon said. "By determining the ages of CAIs and chondrules, we can better date asteroids and planets and learn more about the early history of the solar system."

EROSDAILY

Is Eros An Ancient Planetesimal Leftover From Sol's Birth

Laurel - March 5, 2001
When NASA's Near Earth Asteroid Rendezvous (NEAR) spacecraft left for asteroid 433 Eros five years ago, scientists weren't certain what they would find when the probe arrived. Was Eros a 30-km fragment from a planet that broke apart billions of years ago? Or perhaps a jumble of space boulders barely held together by gravity? Was Eros young or old, tough or fragile .. no one knew for sure.

Thanks for being here; We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain. With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords. Our news coverage takes time and effort to publish 365 days a year. If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor $5 Billed Once credit card or paypal		SpaceDaily Monthly Supporter $5 Billed Monthly paypal only

The content herein, unless otherwise known to be public domain, are Copyright 1995-2016 - 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. 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. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.