Re: [meteorite-list] The Birth of Chondrules
On Fri, 11 Mar 2005 15:17:53 -0500, Anita Westlake [EMAIL PROTECTED] wrote: Check out this article on the birth of chondrules: http://www.rednova.com/news/display/?id=132866 For some reason, Rednova always crashed my web browser. Anyone else have that problem? __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] The Birth of Chondrules
Mine too! Thanks, Tom peregrineflier IMCA 6168 http://www.frontiernet.net/~peregrineflier/Peregrineflier.htm http://fstop.proboards24.com/ - Original Message - From: Darren Garrison [EMAIL PROTECTED] To: meteorite-list@meteoritecentral.com Sent: Friday, March 11, 2005 1:49 PM Subject: Re: [meteorite-list] The Birth of Chondrules On Fri, 11 Mar 2005 15:17:53 -0500, Anita Westlake [EMAIL PROTECTED] wrote: Check out this article on the birth of chondrules: http://www.rednova.com/news/display/?id=132866 For some reason, Rednova always crashed my web browser. Anyone else have that problem? __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list -- No virus found in this incoming message. Checked by AVG Anti-Virus. Version: 7.0.308 / Virus Database: 266.7.1 - Release Date: 3/9/2005 __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] The Birth of Chondrules
Same with me, unless it is opened before I click on the link. Frédéric Beroud www.meteoriteshow.com IMCA # 2491 (http://www.meteoritecollectors.org/) - Original Message - From: Tom Knudson [EMAIL PROTECTED] To: [EMAIL PROTECTED]; meteorite-list@meteoritecentral.com Sent: Friday, March 11, 2005 9:41 PM Subject: Re: [meteorite-list] The Birth of Chondrules Mine too! Thanks, Tom peregrineflier IMCA 6168 http://www.frontiernet.net/~peregrineflier/Peregrineflier.htm http://fstop.proboards24.com/ - Original Message - From: Darren Garrison [EMAIL PROTECTED] To: meteorite-list@meteoritecentral.com Sent: Friday, March 11, 2005 1:49 PM Subject: Re: [meteorite-list] The Birth of Chondrules On Fri, 11 Mar 2005 15:17:53 -0500, Anita Westlake [EMAIL PROTECTED] wrote: Check out this article on the birth of chondrules: http://www.rednova.com/news/display/?id=132866 For some reason, Rednova always crashed my web browser. Anyone else have that problem? __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list -- No virus found in this incoming message. Checked by AVG Anti-Virus. Version: 7.0.308 / Virus Database: 266.7.1 - Release Date: 3/9/2005 __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] The Birth of Chondrules
Darren Garrison wrote: For some reason, Rednova always crashed my web browser. Anyone else have that problem? Here it works fine. Here's the text: Giant Planet Birth Linked to That of Meteorites Carnegie -- Scientists now believe that the formation of Jupiter, the heavy-weight champion of the Solar System's planets, may have spawned some of the tiniest and oldest constituents of our Solar System -- millimeter-sized spheres called chondrules, the major component of primitive meteorites. The study, by theorists Dr. Alan Boss of the Carnegie Institution and Prof. Richard H. Durisen of Indiana University, is published in the March 10, 2005, issue of The Astrophysical Journal (Letters). Understanding what formed the chondrules has been one of biggest problems in the field for over a century, commented Boss. Scientists realized several years ago that a shock wave was probably responsible for generating the heat that cooked these meteoritic components. But no one could explain convincingly how the shock front was generated in the solar nebula some 4.6 billion years ago. These latest calculations show how a shock front could have formed as a result of spiral arms roiling the solar nebula at Jupiter's orbit. The shock front extended into the inner solar nebula, where the compressed gas and radiation heated the dust particles as they struck the shock front at 20,000 mph, thereby creating chondrules, he explained. This calculation has probably removed the last obstacle to acceptance of how chondrules were melted, remarked theorist Dr. Steven Desch of Arizona State University, who showed several years ago that shock waves could do the job. Meteoriticists have recognized that the ways chondrules are melted by shocks are consistent with everything we know about chondrules. But without a proven source of shocks, they have remained mostly unconvinced about how chondrules were melted.The work of Boss and Durisen demonstrates that our early solar nebula experienced the right types of shocks, at the right times, and at the right places in the nebula to melt chondrules. I think for many meteoriticists, this closes the deal. With nebular shocks identified as the culprit, we can finally begin to understand what the chondrules are telling us about the earliest stages of our Solar System's evolution, he concluded. Our calculation shows how the 3-dimensional gravitational forces associated with spiral arms in a gravitationally unstable disk at Jupiter's distance from the Sun (5 times the Earth-Sun distance), would produce a shock wave in the inner solar system (2.5 times the Earth-Sun distance, i.e., in the asteroid belt), Boss continued. It would have heated dust aggregates to the temperature required to melt them and form tiny droplets. Durisen and his research group at Indiana have independently made calculations of gravitationally unstable disks that also support this picture. While Boss is well known as a proponent of the rapid formation of gas giant planets by the disk instability process, the same argument for chondrule formation works for the slower process of core accretion. In order to make Jupiter in either process, the solar nebula had to have been at least marginally gravitationally unstable, so that it would have developed spiral arms early on and resembled a spiral galaxy. Once Jupiter formed by either mechanism, it would have continued to drive shock fronts at asteroidal distances, at least so long as the solar nebula was still around. In both cases, chondrules would have been formed at the very earliest times, and continued to form for a few million years, until the solar nebula disappeared. Late-forming chondrules are thus the last grin of the Cheshire Cat that formed our planetary system. Boss's research is supported in part by the NASA Planetary Geology and Geophysics Program and the NASA Origins of Solar Systems Program. The calculations were performed on the Carnegie Alpha Cluster, the purchase of which was supported in part by the NSF Major Research Instrumentation Program. Durisen's research was also supported in part by the NASA Origins of Solar Systems Program. The Carnegie Institution (www.CarnegieInstitution.org) has been a pioneering force in basic scientific research since 1902. It is a private, nonprofit organization with six research departments throughout the U.S. Carnegie scientists are leaders in plant biology, developmental biology, astronomy, materials science, global ecology, and Earth and planetary science. Cheers, Peter Marmet __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] The Birth of Chondrules
On Fri, 11 Mar 2005 13:21:12 -0800 (PST), Ron Baalke [EMAIL PROTECTED] wrote: Check out this article on the birth of chondrules: http://www.rednova.com/news/display/?id=132866 That's a Carnegie press release that Red Nova copied over. I sent it out already on the list on March 3, but here it is again. Yeah, I thought that it was the recent Jupiter made the chondrules paper. Not to be confused with the also recent gamma ray bursts made the chondrules paper. __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
sunkist29@kiddomail.com was: Re: [meteorite-list] The Birth of Chondrules
I just got another idiotic e-mail from [EMAIL PROTECTED]. I know that others of you are getting them, too. This is obviously some annoying child with access to his parent's computer. Any chance the list'll show that e-mail address the door like was done with Mister Boggy Creek? On Fri, 11 Mar 2005 18:07:25 -0500, [EMAIL PROTECTED] wrote: To: [EMAIL PROTECTED] Subject: Re: Re: [meteorite-list] The Birth of Chondrules From: [EMAIL PROTECTED] Date: Fri, 11 Mar 2005 18:07:25 -0500 stop it it it iyt -= KiddoNet's SAFE email system for kids. Get your own account at http://www.kiddonet.com =- __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] The Birth of Chondrules
As I understand it... most L, LL, H, E, C chondrule formations are thought to have occurred from 4.55 billion to 4.70 billion years ago, with varied dating results typically found when analyzing the different elements in a rock being studied. Whole rock dating gives up an overall average age. I think the idea is that CAI's were formed first, followed by chondrules, followed by carbonates (and matrix material). The whole process for a given chondrite material is thought to have taken no more than a 100 million years. Chump change in time, right ! My novice two cents, John -- Original message from Charles O'Dale [EMAIL PROTECTED]: -- RE: Dating of Chondrules I am researching the absolute ages of chondrules, specifically; Within average chondrites, are all the chondrules the same age or do they vary? If so, by how much? Thanks in advance Charles O'Dale Meeting Chair Ottawa RASC http://www.ottawa.rasc.ca/astronomy/earth_craters/index.html (Pingualuit Crater updated) Date: Fri, 11 Mar 2005 15:17:53 -0500 From: Anita Westlake Subject: [meteorite-list] The Birth of Chondrules To: Message-ID: [EMAIL PROTECTED] Content-Type: text/plain; charset=us-ascii Check out this article on the birth of chondrules: http://www.rednova.com/news/display/?id=132866 Anita D. Westlake __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
