Re: [meteorite-list] New Australian fall
Carl E. Did you ever get a response to your question on whether aubrites could possibly come from the Earth? Very interesting thoughts, to be sure, but I believe Sterling inferred that as a possibility. I also believe his last sentence says it all, I guess. As a side note, if aubrites did come from the Earth, What is the probability or possibility that they would contain some fossils? Microbes, sea shells, plant life...? Even water? If no fossils would that be compelling enough that they did not come from Earth? Carl Carl E wrote: Sterling, This may not surprise you but, I did not know that aubrites plotted on the same oxygen slope line as Earth and our Moon. Does this mean that Aubrites could possibly be meteorites from Earth? I believe it was decided earlier they would be called terranemeteorites?... Sterling wrote: ...For example, aubrites and lunar achondrites plot on the terrestrial ratio slope, meaning that the Earth and the Moon and the Wherever-the- aubrites-came-from all have the SAME oxygen ratios... and, ...As usual, too little data for ANY conclusion. The connection with the Bottke study is likely purely hypothetical. In other words, a guess. There's nothing you can say about nothing. _ Insert movie times and more without leaving Hotmail®. http://windowslive.com/Tutorial/Hotmail/QuickAdd?ocid=TXT_TAGLM_WL_HM_Tutorial_QuickAdd_062009 __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall
Sterling, This may not surprise you but, I did not know that aubrites plotted on the same oxygen slope line as Earth and our Moon. Does this mean that Aubrites could possibly be meteorites from Earth? I believe it was decided earlier they would be called terranemeteorites? Has this previously been discussed here on this list? I ask because don't we also apply a lot of weight to oxygen isotopes in determining if rocks indeed came from Mars? Sort of like if the glove fits? Or if it don't fit, you must acquit? Carl E. -- Carl or Debbie Esparza IMCA 5829 Meteoritemax Sterling K. Webb sterling_k_w...@sbcglobal.net wrote: Hi, Jason, List The word eucrite comes from the Greek and means easily recognized. It was coined to describe terrestrial basalts and only later was it applied to meteorites, and to the most common of achondrites. It is no longer used for Earthly rocks. They are basalts from lava flows on the surface of a differentiated body. They're just ordinary basaltic rocks, only from somewhere other than Earth. The oxygen data is tricky. You plot the slope of the ratios of O17 or O18 to O16 for each rock. Those that land on the same slope are not always from the same body, because different bodies may have the same oxygen ratios. For example, aubrites and lunar achondrites plot on the terrestrial ratio slope, meaning that the Earth and the Moon and the Wherever-the- aubrites-came-from all have the SAME oxygen ratios. Eucrites from Vesta plot along a slope all their own. I assume what the reporter said of what Bland said meant that this eucrite does not plot on the Vestan slope. We have no idea of what slope it plots on; as is usual with press reports, there is no usable information in them. What slope did it plot on? Who knows? Bland does; we're guessing without data. If he knew the body it came from, it would be big news and he would have told it. Shouted it, actually... So, it is a basalt lava flow from the crust of SOME other body than Vesta or a Vestoid, but otherwise not known. It's a breccia with clasts so that body has an impact-altered surface. We have exsolution so it was (once) a big enough body to have cooled slowly. Equally vague and useless are the press release level comments about inner solar system orbits. Numbers are the only thing with meaning. Semi-major axis in AU, please, eccentricity, etc. NOT knocking the scientist speaking, only the reporter listening to stuff he knows nothing about. It's like sending your five-year-old to talk to your Congressman, and then come back and tell you what he said about health care reform. Meaningless. The Scientific American article is, if anything, more vague. The mention of Bottke and SWR studies probably means the study that showed that many members of the inner asteroid zone were tossed there from the very inner solar system, 0.5 AU, particularly the big iron asteroids. This little eucrite could be a chunk of the largely battered-away former crust of Mercury, for example. Put a lander on Mercury and measure the oxygen ratios and we'll know. As usual, too little data for ANY conclusion. The connection with the Bottke study is likely purely hypothetical. In other words, a guess. There's nothing you can say about nothing. Sterling K. Webb -- - Original Message - From: Jason Utas meteorite...@gmail.com To: Meteorite-list meteorite-list@meteoritecentral.com Sent: Friday, September 18, 2009 8:45 PM Subject: Re: [meteorite-list] New Australian fall Good point; and seeing as such meteorites haven't been reclassified/re-typed, it seems as though this brings up a very valid flaw in the classification system of basaltic achondrites. Perhaps there are some scientists out there who can shed some light on why meteorites such as these are called Eucrites when they are apparently from different parent bodies. I'd be curious of the general scientific opinion of the current classification scheme; is it adequate or should there be more, if not classes, at least meteorites deemed 'ungrouped.' Jason On Fri, Sep 18, 2009 at 6:37 PM, Michael Fowler mqfow...@mac.com wrote: And in case you didn't check the met-bull, the Bunburra Rockhole meteorite has been classified as a typical Eucrite. He stated that said meteorite is not from Vesta, but Eucrites are widely accepted to have come from Vesta. I suppose we don't have solid proof of that yet, but it is generally accepted to be true, based on reflected light analyses. Go figure. Jason Hi Jason, Sorry if I ruffled your feathers earlier. I did check the met bulletin, and it is described as: meteorite is a basaltic eucrite monomict breccia http://tin.er.usgs.gov/meteor/index.php?code=48653 However I note that many meteorites are not correctly
[meteorite-list] New Australian fall
http://www.smh.com.au/technology/sci-tech/rare-snapshot-of-solar-systems-dawn-20090918-fvcl.html Rare snapshot of solar system's dawn DEBORAH SMITH SCIENCE EDITOR September 19, 2009 CAMERAS set up in outback Australia to track fireballs across the night sky have led scientists to a rare meteorite formed at the dawn of the solar system. The fiery streak it made on descent allowed them not only to pinpoint where it would fall on the vast Nullarbor Plain, but also work out where it had come from. Three fragments of the meteorite, the biggest the size of a cricket ball, were found within 100 metres of the predicted landing site, Alex Bevan, head of earth and planetary science at the Western Australian Museum, said. ''That is incredible accuracy.'' Dr Bevan said the Nullarbor desert was chosen for a new fireball observatory because of its pale limestone colour. ''Most meteorites are dark so they contrast well with the local rock.'' Dubbed Bunburra Rockhole after a nearby landmark, the meteorite was found on the first day of searching by the international team, which includes researchers from the Perth museum and CSIRO. Meteorites are among the most studied rocks on Earth, the team leader, Philip Bland, of the Imperial College in London, said. ''But it's really rare for us to be able to tell where they came from.'' Based on its unusual basalt composition and trajectory, the researchers believe the Nullarbor meteorite was once part of an asteroid in the innermost side of the asteroid belt between Mars and Jupiter, until a collision chipped it off millions of years ago. It then moved into an orbit around the sun similar to that of Earth, before plummeting to the ground on July 20, 2007. Weighing about 22 kilograms when it began its fiery descent at an altitude of 60 kilometres, only fragments of less than 200 grams were left when it hit. ''We're cautiously optimistic that this find could be the first of many, and if that happens, each find may give us more clues about how the solar system began,'' Dr Bland, whose team's study was published yesterday in the journal Science, said. Asteroids in the innermost belt are thought to have formed near the sun and consist of the same material from which the earth was made. The fireball observatory consists of a network of four cameras that take a single time-lapse picture every night to track any shooting stars, and complex mathematics is required to determine a meteorite's original orbit. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall
Looks like a nice eucrite. Similar to Camel Donga. Matt -- Matt Morgan Mile High Meteorites http://www.mhmeteorites.com P.O. Box 151293 Lakewood, CO 80215 USA -Original Message- From: Darren Garrison cyna...@charter.net Date: Fri, 18 Sep 2009 12:51:04 To: meteorite-list@meteoritecentral.com Subject: [meteorite-list] New Australian fall http://www.smh.com.au/technology/sci-tech/rare-snapshot-of-solar-systems-dawn-20090918-fvcl.html Rare snapshot of solar system's dawn DEBORAH SMITH SCIENCE EDITOR September 19, 2009 CAMERAS set up in outback Australia to track fireballs across the night sky have led scientists to a rare meteorite formed at the dawn of the solar system. The fiery streak it made on descent allowed them not only to pinpoint where it would fall on the vast Nullarbor Plain, but also work out where it had come from. Three fragments of the meteorite, the biggest the size of a cricket ball, were found within 100 metres of the predicted landing site, Alex Bevan, head of earth and planetary science at the Western Australian Museum, said. ''That is incredible accuracy.'' Dr Bevan said the Nullarbor desert was chosen for a new fireball observatory because of its pale limestone colour. ''Most meteorites are dark so they contrast well with the local rock.'' Dubbed Bunburra Rockhole after a nearby landmark, the meteorite was found on the first day of searching by the international team, which includes researchers from the Perth museum and CSIRO. Meteorites are among the most studied rocks on Earth, the team leader, Philip Bland, of the Imperial College in London, said. ''But it's really rare for us to be able to tell where they came from.'' Based on its unusual basalt composition and trajectory, the researchers believe the Nullarbor meteorite was once part of an asteroid in the innermost side of the asteroid belt between Mars and Jupiter, until a collision chipped it off millions of years ago. It then moved into an orbit around the sun similar to that of Earth, before plummeting to the ground on July 20, 2007. Weighing about 22 kilograms when it began its fiery descent at an altitude of 60 kilometres, only fragments of less than 200 grams were left when it hit. ''We're cautiously optimistic that this find could be the first of many, and if that happens, each find may give us more clues about how the solar system began,'' Dr Bland, whose team's study was published yesterday in the journal Science, said. Asteroids in the innermost belt are thought to have formed near the sun and consist of the same material from which the earth was made. The fireball observatory consists of a network of four cameras that take a single time-lapse picture every night to track any shooting stars, and complex mathematics is required to determine a meteorite's original orbit. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall
FAR OUT! -- From: Darren Garrison cyna...@charter.net Sent: Friday, September 18, 2009 1:51 PM To: meteorite-list@meteoritecentral.com Subject: [meteorite-list] New Australian fall http://www.smh.com.au/technology/sci-tech/rare-snapshot-of-solar-systems-dawn-20090918-fvcl.html Rare snapshot of solar system's dawn DEBORAH SMITH SCIENCE EDITOR September 19, 2009 CAMERAS set up in outback Australia to track fireballs across the night sky have led scientists to a rare meteorite formed at the dawn of the solar system. The fiery streak it made on descent allowed them not only to pinpoint where it would fall on the vast Nullarbor Plain, but also work out where it had come from. Three fragments of the meteorite, the biggest the size of a cricket ball, were found within 100 metres of the predicted landing site, Alex Bevan, head of earth and planetary science at the Western Australian Museum, said. ''That is incredible accuracy.'' Dr Bevan said the Nullarbor desert was chosen for a new fireball observatory because of its pale limestone colour. ''Most meteorites are dark so they contrast well with the local rock.'' Dubbed Bunburra Rockhole after a nearby landmark, the meteorite was found on the first day of searching by the international team, which includes researchers from the Perth museum and CSIRO. Meteorites are among the most studied rocks on Earth, the team leader, Philip Bland, of the Imperial College in London, said. ''But it's really rare for us to be able to tell where they came from.'' Based on its unusual basalt composition and trajectory, the researchers believe the Nullarbor meteorite was once part of an asteroid in the innermost side of the asteroid belt between Mars and Jupiter, until a collision chipped it off millions of years ago. It then moved into an orbit around the sun similar to that of Earth, before plummeting to the ground on July 20, 2007. Weighing about 22 kilograms when it began its fiery descent at an altitude of 60 kilometres, only fragments of less than 200 grams were left when it hit. ''We're cautiously optimistic that this find could be the first of many, and if that happens, each find may give us more clues about how the solar system began,'' Dr Bland, whose team's study was published yesterday in the journal Science, said. Asteroids in the innermost belt are thought to have formed near the sun and consist of the same material from which the earth was made. The fireball observatory consists of a network of four cameras that take a single time-lapse picture every night to track any shooting stars, and complex mathematics is required to determine a meteorite's original orbit. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall
The fall actually happened in 2007, Meteoritical Bulletin: MB 95 http://tin.er.usgs.gov/meteor/docs/mb95.pdf . I heard of it in February this year. The location is between Mundrabilla and Cook 001. Coordinates are 31° 21.0'S, 129° 11.4'E, that means 168.6 km east of Mundrabilla and 170.9 km south west of cook 001. Unfortunately no fragments have been available for collectors. Cheers, and best regards from Down-Under, Norbert Kammel IMCA # 3420 Matt Morgan wrote: Looks like a nice eucrite. Similar to Camel Donga. Matt -- Matt Morgan Mile High Meteorites http://www.mhmeteorites.com P.O. Box 151293 Lakewood, CO 80215 USA -Original Message- From: Darren Garrison cyna...@charter.net Date: Fri, 18 Sep 2009 12:51:04 To: meteorite-list@meteoritecentral.com Subject: [meteorite-list] New Australian fall http://www.smh.com.au/technology/sci-tech/rare-snapshot-of-solar-systems-dawn-20090918-fvcl.html Rare snapshot of solar system's dawn DEBORAH SMITH SCIENCE EDITOR September 19, 2009 CAMERAS set up in outback Australia to track fireballs across the night sky have led scientists to a rare meteorite formed at the dawn of the solar system. The fiery streak it made on descent allowed them not only to pinpoint where it would fall on the vast Nullarbor Plain, but also work out where it had come from. Three fragments of the meteorite, the biggest the size of a cricket ball, were found within 100 metres of the predicted landing site, Alex Bevan, head of earth and planetary science at the Western Australian Museum, said. ''That is incredible accuracy.'' Dr Bevan said the Nullarbor desert was chosen for a new fireball observatory because of its pale limestone colour. ''Most meteorites are dark so they contrast well with the local rock.'' Dubbed Bunburra Rockhole after a nearby landmark, the meteorite was found on the first day of searching by the international team, which includes researchers from the Perth museum and CSIRO. Meteorites are among the most studied rocks on Earth, the team leader, Philip Bland, of the Imperial College in London, said. ''But it's really rare for us to be able to tell where they came from.'' Based on its unusual basalt composition and trajectory, the researchers believe the Nullarbor meteorite was once part of an asteroid in the innermost side of the asteroid belt between Mars and Jupiter, until a collision chipped it off millions of years ago. It then moved into an orbit around the sun similar to that of Earth, before plummeting to the ground on July 20, 2007. Weighing about 22 kilograms when it began its fiery descent at an altitude of 60 kilometres, only fragments of less than 200 grams were left when it hit. ''We're cautiously optimistic that this find could be the first of many, and if that happens, each find may give us more clues about how the solar system began,'' Dr Bland, whose team's study was published yesterday in the journal Science, said. Asteroids in the innermost belt are thought to have formed near the sun and consist of the same material from which the earth was made. The fireball observatory consists of a network of four cameras that take a single time-lapse picture every night to track any shooting stars, and complex mathematics is required to determine a meteorite's original orbit. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall
Hi Matt, I don't see a pic. Carl _ Hotmail® has ever-growing storage! Don’t worry about storage limits. http://windowslive.com/Tutorial/Hotmail/Storage?ocid=TXT_TAGLM_WL_HM_Tutorial_Storage_062009 __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall
Hola, Wha-la - Photos: http://www.eurekalert.org/multimedia/pub/16856.php http://www.news.com.au/perthnow/story/0,27574,26090814-2761,00.html And I think it might be interesting to note this article, where Dr. Philip Bland can be quoted as stating that Eucrites are not, in fact, from Vesta. Go figure. http://au.news.yahoo.com/a/-/technology/6075299/rare-meteorite-found-in-outback/ Regards, Jason On Fri, Sep 18, 2009 at 3:29 PM, Carl 's carloselgua...@hotmail.com wrote: Hi Matt, I don't see a pic. Carl _ Hotmail® has ever-growing storage! Don’t worry about storage limits. http://windowslive.com/Tutorial/Hotmail/Storage?ocid=TXT_TAGLM_WL_HM_Tutorial_Storage_062009 __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall
And I think it might be interesting to note this article, where Dr. Philip Bland can be quoted as stating that Eucrites are not, in fact, from Vesta. Go figure. http://au.news.yahoo.com/a/-/technology/6075299/rare-meteorite-found-in-outback/ Regards, Jason Jason, You were a little bit hasty or misleading in your summarizing of Dr Bland. see quote below from the article you cited. (and to think that we are always criticizing reporters for getting it wrong!) Mike Fowler Chicago Dr Bland says most basalt meteorites, like the one found in the Nullarbor, originate from a large asteroid called Vesta but the Bunburra Rockhole meteorite is different. Our little guy can't be from Vesta, the composition is all wrong, he said. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall-Non Vesta Eucrite
Additional information from a Scientific American link that says that the meteorite is not from Vesta, because the orbit is wrong, and the oxygen isotopes are different. http://www.scientificamerican.com/blog/60-second-science/post.cfm?id=recovered-meteorite-points-to-an-un-2009-09-17 Mike Fowler Chicago And I think it might be interesting to note this article, where Dr. Philip Bland can be quoted as stating that Eucrites are not, in fact, from Vesta. Go figure. http://au.news.yahoo.com/a/-/technology/6075299/rare-meteorite-found-in-outback/ Regards, Jason Jason, You were a little bit hasty or misleading in your summarizing of Dr Bland. see quote below from the article you cited. (and to think that we are always criticizing reporters for getting it wrong!) Mike Fowler Chicago Dr Bland says most basalt meteorites, like the one found in the Nullarbor, originate from a large asteroid called Vesta but the Bunburra Rockhole meteorite is different. Our little guy can't be from Vesta, the composition is all wrong, he said. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall
And in case you didn't check the met-bull, the Bunburra Rockhole meteorite has been classified as a typical Eucrite. He stated that said meteorite is not from Vesta, but Eucrites are widely accepted to have come from Vesta. I suppose we don't have solid proof of that yet, but it is generally accepted to be true, based on reflected light analyses. Go figure. Jason On Fri, Sep 18, 2009 at 5:39 PM, Michael Fowler mqfow...@mac.com wrote: And I think it might be interesting to note this article, where Dr. Philip Bland can be quoted as stating that Eucrites are not, in fact, from Vesta. Go figure. http://au.news.yahoo.com/a/-/technology/6075299/rare-meteorite-found-in-outback/ Regards, Jason Jason, You were a little bit hasty or misleading in your summarizing of Dr Bland. see quote below from the article you cited. (and to think that we are always criticizing reporters for getting it wrong!) Mike Fowler Chicago Dr Bland says most basalt meteorites, like the one found in the Nullarbor, originate from a large asteroid called Vesta but the Bunburra Rockhole meteorite is different. Our little guy can't be from Vesta, the composition is all wrong, he said. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall-Non Vesta Eucrite
Well, oxygen isotopes are one thing, but orbital data would seem to be a strange way to classify a meteorite to me; given the past four and a half billion years of collisions, things have been far too 'messed up' in the inner solar system for that to mean much; we have comets present in stable orbits here in the innrer solar system, and it doesn't mean that they formed there. And most would also make a clear definition between chemical and isotopic data, which he confuses (or the reference was a misquote) in the article. After all, Ibitira's a Eucrite, but NWA 011's an ungrouped achondrite. It's the chemical difference that seems to make the difference in nomenclature. Jason On Fri, Sep 18, 2009 at 5:47 PM, Michael Fowler mqfow...@mac.com wrote: Additional information from a Scientific American link that says that the meteorite is not from Vesta, because the orbit is wrong, and the oxygen isotopes are different. http://www.scientificamerican.com/blog/60-second-science/post.cfm?id=recovered-meteorite-points-to-an-un-2009-09-17 Mike Fowler Chicago And I think it might be interesting to note this article, where Dr. Philip Bland can be quoted as stating that Eucrites are not, in fact, from Vesta. Go figure. http://au.news.yahoo.com/a/-/technology/6075299/rare-meteorite-found-in-outback/ Regards, Jason Jason, You were a little bit hasty or misleading in your summarizing of Dr Bland. see quote below from the article you cited. (and to think that we are always criticizing reporters for getting it wrong!) Mike Fowler Chicago Dr Bland says most basalt meteorites, like the one found in the Nullarbor, originate from a large asteroid called Vesta but the Bunburra Rockhole meteorite is different. Our little guy can't be from Vesta, the composition is all wrong, he said. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall
And in case you didn't check the met-bull, the Bunburra Rockhole meteorite has been classified as a typical Eucrite. He stated that said meteorite is not from Vesta, but Eucrites are widely accepted to have come from Vesta. I suppose we don't have solid proof of that yet, but it is generally accepted to be true, based on reflected light analyses. Go figure. Jason Hi Jason, Sorry if I ruffled your feathers earlier. I did check the met bulletin, and it is described as: meteorite is a basaltic eucrite monomict breccia http://tin.er.usgs.gov/meteor/index.php?code=48653 However I note that many meteorites are not correctly classified on their first appearance in the Met Bul, including of course Ibitria, which is still listed as a Eucrite Monomict, even though we know it is not from Vesta, http://tin.er.usgs.gov/meteor/index.php?sea=ibitirasfor=namesants=falls=valids=stype=containslrec=50map=gebrowse=country=Allsrt=namecateg=Allmblist=Allrect=phot=snew=0pnt=nocode=11993 However back to, Bunburra Rockhole, can someone comment or whether the mineral composition as stated in the met bul is consistent, or anomalous for a eucrite? Mineral compositions: Pyroxene, Fs62.5Wo3.6 (Fe/Mn-31.1) with augite (Fs27.7Wo43.0) lamellae; plagioclase, An84.1 to An88.2. Of course, the final word is probably the O isotope work, which Dr Bland says has already been done, although I couldn't find any additional reference. Thanks, Mike __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall
Good point; and seeing as such meteorites haven't been reclassified/re-typed, it seems as though this brings up a very valid flaw in the classification system of basaltic achondrites. Perhaps there are some scientists out there who can shed some light on why meteorites such as these are called Eucrites when they are apparently from different parent bodies. I'd be curious of the general scientific opinion of the current classification scheme; is it adequate or should there be more, if not classes, at least meteorites deemed 'ungrouped.' Jason On Fri, Sep 18, 2009 at 6:37 PM, Michael Fowler mqfow...@mac.com wrote: And in case you didn't check the met-bull, the Bunburra Rockhole meteorite has been classified as a typical Eucrite. He stated that said meteorite is not from Vesta, but Eucrites are widely accepted to have come from Vesta. I suppose we don't have solid proof of that yet, but it is generally accepted to be true, based on reflected light analyses. Go figure. Jason Hi Jason, Sorry if I ruffled your feathers earlier. I did check the met bulletin, and it is described as: meteorite is a basaltic eucrite monomict breccia http://tin.er.usgs.gov/meteor/index.php?code=48653 However I note that many meteorites are not correctly classified on their first appearance in the Met Bul, including of course Ibitria, which is still listed as a Eucrite Monomict, even though we know it is not from Vesta, http://tin.er.usgs.gov/meteor/index.php?sea=ibitirasfor=namesants=falls=valids=stype=containslrec=50map=gebrowse=country=Allsrt=namecateg=Allmblist=Allrect=phot=snew=0pnt=nocode=11993 However back to, Bunburra Rockhole, can someone comment or whether the mineral composition as stated in the met bul is consistent, or anomalous for a eucrite? Mineral compositions: Pyroxene, Fs62.5Wo3.6 (Fe/Mn-31.1) with augite (Fs27.7Wo43.0) lamellae; plagioclase, An84.1 to An88.2. Of course, the final word is probably the O isotope work, which Dr Bland says has already been done, although I couldn't find any additional reference. Thanks, Mike __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall-Non Vesta Eucrite
After all, Ibitira's a Eucrite, but NWA 011's an ungrouped achondrite. It's the chemical difference that seems to make the difference in nomenclature. Jason So Jason, I guess we can both agree that Bunburra Rockhole is a Eucrite, and that most Eucrites, but not all, come from Vesta. Mike __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall
That's right. In fact it was approved and added to the Met Bull database earlier this year: http://tin.er.usgs.gov/meteor/index.php?code=48653 Cheers, Jeff - Original Message - From: Norbert Heike Kammel meteori...@optushome.com.au To: m...@mhmeteorites.com Cc: meteorite-list@meteoritecentral.com Sent: Saturday, September 19, 2009 8:21 AM Subject: Re: [meteorite-list] New Australian fall The fall actually happened in 2007, Meteoritical Bulletin: MB 95 http://tin.er.usgs.gov/meteor/docs/mb95.pdf . I heard of it in February this year. The location is between Mundrabilla and Cook 001. Coordinates are 31° 21.0'S, 129° 11.4'E, that means 168.6 km east of Mundrabilla and 170.9 km south west of cook 001. Unfortunately no fragments have been available for collectors. Cheers, and best regards from Down-Under, Norbert Kammel IMCA # 3420 Matt Morgan wrote: Looks like a nice eucrite. Similar to Camel Donga. Matt -- Matt Morgan Mile High Meteorites http://www.mhmeteorites.com P.O. Box 151293 Lakewood, CO 80215 USA -Original Message- From: Darren Garrison cyna...@charter.net Date: Fri, 18 Sep 2009 12:51:04 To: meteorite-list@meteoritecentral.com Subject: [meteorite-list] New Australian fall http://www.smh.com.au/technology/sci-tech/rare-snapshot-of-solar-systems-dawn-20090918-fvcl.html Rare snapshot of solar system's dawn DEBORAH SMITH SCIENCE EDITOR September 19, 2009 CAMERAS set up in outback Australia to track fireballs across the night sky have led scientists to a rare meteorite formed at the dawn of the solar system. The fiery streak it made on descent allowed them not only to pinpoint where it would fall on the vast Nullarbor Plain, but also work out where it had come from. Three fragments of the meteorite, the biggest the size of a cricket ball, were found within 100 metres of the predicted landing site, Alex Bevan, head of earth and planetary science at the Western Australian Museum, said. ''That is incredible accuracy.'' Dr Bevan said the Nullarbor desert was chosen for a new fireball observatory because of its pale limestone colour. ''Most meteorites are dark so they contrast well with the local rock.'' Dubbed Bunburra Rockhole after a nearby landmark, the meteorite was found on the first day of searching by the international team, which includes researchers from the Perth museum and CSIRO. Meteorites are among the most studied rocks on Earth, the team leader, Philip Bland, of the Imperial College in London, said. ''But it's really rare for us to be able to tell where they came from.'' Based on its unusual basalt composition and trajectory, the researchers believe the Nullarbor meteorite was once part of an asteroid in the innermost side of the asteroid belt between Mars and Jupiter, until a collision chipped it off millions of years ago. It then moved into an orbit around the sun similar to that of Earth, before plummeting to the ground on July 20, 2007. Weighing about 22 kilograms when it began its fiery descent at an altitude of 60 kilometres, only fragments of less than 200 grams were left when it hit. ''We're cautiously optimistic that this find could be the first of many, and if that happens, each find may give us more clues about how the solar system began,'' Dr Bland, whose team's study was published yesterday in the journal Science, said. Asteroids in the innermost belt are thought to have formed near the sun and consist of the same material from which the earth was made. The fireball observatory consists of a network of four cameras that take a single time-lapse picture every night to track any shooting stars, and complex mathematics is required to determine a meteorite's original orbit. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall
Hi jason and Mike Fowler, It's been a privilege to be able to eavesdrop on your discussion on this other body eucrite. You have been most informative and professional. Thanks! Carl _ Microsoft brings you a new way to search the web. Try Bing™ now http://www.bing.com?form=MFEHPGpubl=WLHMTAGcrea=TEXT_MFEHPG_Core_tagline_try bing_1x1 __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall-Non Vesta Eucrite
I don't think there's a difference between any of these meteorites in terms of what we should call them. We just don't have consistent terminology in place. Ibitira, NWA 011, and, it appears, Bunburra Rockhole are all basaltic achondrites that seem to come from a separate parent body than other basaltic achondrites. In my opinion, none of these should be called a eucrite, just as we don't call angrites eucrites. I would prefer to call them ungrouped basaltic achondrites. If I had a peer-reviewed reference that handled the nomenclature well, I'd change the recommended classifications in the MetBull database. Jeff Jason Utas wrote: Well, oxygen isotopes are one thing, but orbital data would seem to be a strange way to classify a meteorite to me; given the past four and a half billion years of collisions, things have been far too 'messed up' in the inner solar system for that to mean much; we have comets present in stable orbits here in the innrer solar system, and it doesn't mean that they formed there. And most would also make a clear definition between chemical and isotopic data, which he confuses (or the reference was a misquote) in the article. After all, Ibitira's a Eucrite, but NWA 011's an ungrouped achondrite. It's the chemical difference that seems to make the difference in nomenclature. Jason On Fri, Sep 18, 2009 at 5:47 PM, Michael Fowler mqfow...@mac.com wrote: Additional information from a Scientific American link that says that the meteorite is not from Vesta, because the orbit is wrong, and the oxygen isotopes are different. http://www.scientificamerican.com/blog/60-second-science/post.cfm?id=recovered-meteorite-points-to-an-un-2009-09-17 Mike Fowler Chicago And I think it might be interesting to note this article, where Dr. Philip Bland can be quoted as stating that Eucrites are not, in fact, from Vesta. Go figure. http://au.news.yahoo.com/a/-/technology/6075299/rare-meteorite-found-in-outback/ Regards, Jason Jason, You were a little bit hasty or misleading in your summarizing of Dr Bland. see quote below from the article you cited. (and to think that we are always criticizing reporters for getting it wrong!) Mike Fowler Chicago Dr Bland says most basalt meteorites, like the one found in the Nullarbor, originate from a large asteroid called Vesta but the Bunburra Rockhole meteorite is different. Our little guy can't be from Vesta, the composition is all wrong, he said. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list -- Dr. Jeffrey N. Grossman phone: (703) 648-6184 US Geological Survey fax: (703) 648-6383 954 National Center Reston, VA 20192, USA __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] New Australian fall
Hi, Jason, List The word eucrite comes from the Greek and means easily recognized. It was coined to describe terrestrial basalts and only later was it applied to meteorites, and to the most common of achondrites. It is no longer used for Earthly rocks. They are basalts from lava flows on the surface of a differentiated body. They're just ordinary basaltic rocks, only from somewhere other than Earth. The oxygen data is tricky. You plot the slope of the ratios of O17 or O18 to O16 for each rock. Those that land on the same slope are not always from the same body, because different bodies may have the same oxygen ratios. For example, aubrites and lunar achondrites plot on the terrestrial ratio slope, meaning that the Earth and the Moon and the Wherever-the- aubrites-came-from all have the SAME oxygen ratios. Eucrites from Vesta plot along a slope all their own. I assume what the reporter said of what Bland said meant that this eucrite does not plot on the Vestan slope. We have no idea of what slope it plots on; as is usual with press reports, there is no usable information in them. What slope did it plot on? Who knows? Bland does; we're guessing without data. If he knew the body it came from, it would be big news and he would have told it. Shouted it, actually... So, it is a basalt lava flow from the crust of SOME other body than Vesta or a Vestoid, but otherwise not known. It's a breccia with clasts so that body has an impact-altered surface. We have exsolution so it was (once) a big enough body to have cooled slowly. Equally vague and useless are the press release level comments about inner solar system orbits. Numbers are the only thing with meaning. Semi-major axis in AU, please, eccentricity, etc. NOT knocking the scientist speaking, only the reporter listening to stuff he knows nothing about. It's like sending your five-year-old to talk to your Congressman, and then come back and tell you what he said about health care reform. Meaningless. The Scientific American article is, if anything, more vague. The mention of Bottke and SWR studies probably means the study that showed that many members of the inner asteroid zone were tossed there from the very inner solar system, 0.5 AU, particularly the big iron asteroids. This little eucrite could be a chunk of the largely battered-away former crust of Mercury, for example. Put a lander on Mercury and measure the oxygen ratios and we'll know. As usual, too little data for ANY conclusion. The connection with the Bottke study is likely purely hypothetical. In other words, a guess. There's nothing you can say about nothing. Sterling K. Webb -- - Original Message - From: Jason Utas meteorite...@gmail.com To: Meteorite-list meteorite-list@meteoritecentral.com Sent: Friday, September 18, 2009 8:45 PM Subject: Re: [meteorite-list] New Australian fall Good point; and seeing as such meteorites haven't been reclassified/re-typed, it seems as though this brings up a very valid flaw in the classification system of basaltic achondrites. Perhaps there are some scientists out there who can shed some light on why meteorites such as these are called Eucrites when they are apparently from different parent bodies. I'd be curious of the general scientific opinion of the current classification scheme; is it adequate or should there be more, if not classes, at least meteorites deemed 'ungrouped.' Jason On Fri, Sep 18, 2009 at 6:37 PM, Michael Fowler mqfow...@mac.com wrote: And in case you didn't check the met-bull, the Bunburra Rockhole meteorite has been classified as a typical Eucrite. He stated that said meteorite is not from Vesta, but Eucrites are widely accepted to have come from Vesta. I suppose we don't have solid proof of that yet, but it is generally accepted to be true, based on reflected light analyses. Go figure. Jason Hi Jason, Sorry if I ruffled your feathers earlier. I did check the met bulletin, and it is described as: meteorite is a basaltic eucrite monomict breccia http://tin.er.usgs.gov/meteor/index.php?code=48653 However I note that many meteorites are not correctly classified on their first appearance in the Met Bul, including of course Ibitria, which is still listed as a Eucrite Monomict, even though we know it is not from Vesta, http://tin.er.usgs.gov/meteor/index.php?sea=ibitirasfor=namesants=falls=valids=stype=containslrec=50map=gebrowse=country=Allsrt=namecateg=Allmblist=Allrect=phot=snew=0pnt=nocode=11993 However back to, Bunburra Rockhole, can someone comment or whether the mineral composition as stated in the met bul is consistent, or anomalous for a eucrite? Mineral compositions: Pyroxene, Fs62.5Wo3.6 (Fe/Mn-31.1) with augite (Fs27.7Wo43.0) lamellae; plagioclase, An84.1 to An88.2. Of course, the final word is probably the O isotope work, which Dr Bland says has already been done, although I couldn't find any
