[meteorite-list] Brownlees in Rainwater
From: Jerry <grf2_at_meteoritecentral.com>
Date: Tue, 20 Nov 2007 21:12:20 -0500 Message-ID: <66119E475E6940FFA9DDED4D44597BF0_at_Notebook> Thanks Doug, I think I may tinker around with those ideas and some of mine. Jerry Flaherty ----- Original Message ----- From: "mexicodoug" <mexicodoug at aol.com> To: "Jerry" <grf2 at verizon.net>; <meteorite-list at meteoritecentral.com> Sent: Tuesday, November 20, 2007 8:16 PM Subject: Re: [meteorite-list] Brownlees in Rainwater > Jerry wrote: > "Would the Noise material contain Ni? If that were the case a simple test > for Ni might be a step toward separatng vast amounts of noise from more > potentially meteoric stuff." > > Hi Jerry, > > Maybe theoretically. > > Keeping in mind that Bessey specs would be reasonably bigger than most of > these - I think you have an assumption built into your question: That > micrometeorites are similar compositionally to most of the meteorites we > get our hands on. I am not sure that this is the case, or even for that > matter that a magnet is picking up the authentic micrometeorites. From > what I've read, which is very, very minimal, many "analyzed" > micrometeorites are most similar to carbonaceous chondrites and most > specifically CI or CM chondrites (and this builds part of the case to link > them to comets). The nickel content in these tiny particles would be > around 1% or even less. If anything, then, I would think the best bet > would be to run a "refrigerator" magnet over gutter recovered material and > throw out anything that actually stuck to it. Then, use a super neodymium > magnet and see which specs stick to it (and, unfortunately magnetizing > what little metal is in it), and keep those as candidates and throw the > rest away including the particles from the Moon. On the other hand, maybe > some metal particles are concentrated residue from ablation, but those > would be so altered, that a trace of Iridium might be there...I'd be > interested in looking for traces of amino acids, too, for example. > > How you would sort the tiny sub-mg particle containing a not-uniformly > distributed 3 micrograms of nickel without being an ace microprobeist > going nuts on a beachful of grains, sounds difficult to me. And what I > suggest, too, also relies on assumptions of composition which is circular > logic. The stuff collected from blocks of old ice or other natural traps > is pristine, though, and could serve as somewhat of a control. The > trouble with it though, is that it is hard to know if it is representative > of what is accumulating today. > > I am not sure an ocassional event like Tunguska, for example, wouldn't > provide most of the particles, or say the year following Sikhote, when > looking at these reserviors. On the other hand, there is no reason the > majority of micrometeorites would be the same as meteorites in our > collections, because as Larry hazarded a guess, they are probably cometary > in origin, perhaps like some of the "sparks" seen at the end of the > Leonids' trails, and there is no warranty that we have anything exactly > like them in our collections. (Or, to Francis' line of thinking, reflect > major events of Lunar dust kicked up at some point from a major cratering > event there like the one reputed to have happened in the 1100's.) > > Everything seems to have problems, so this sounds to me like it is a good > case for a lot of grunt work and a very huge experimental design covering > sampling techniques, with special interest toward developing data in say, > the week following major meteor showers. Maybe NASA and collaborating > reseachers have this covered from planes and balloons, but I bet even > their sampling techniques bias the results knowingly and in ways not even > recognized by them? > > Whoever is analyzing the Stardust samples (Would that happen to be > Brownlee? :-) ), and what instruments and techniques are being used, would > probably laugh at this, but those're the thoughts from the peanut gallery. > > Best wishes and Great Health, > Doug > > > ----- Original Message ----- > From: "Jerry" <grf2 at verizon.net> > To: "mexicodoug" <mexicodoug at aol.com>; "Francis Graham" > <francisgraham at rocketmail.com>; <meteorite-list at meteoritecentral.com> > Sent: Tuesday, November 20, 2007 3:21 PM > Subject: Re: [meteorite-list] Brownlees in Rainwater > > >> Doug, Francis, Chris and List, >> Some might remember my post on this subject a year or so ago. >> I addressed the possibility of actually getting real micrometeorites >> using similar techniques [magnets] >> I referred to a leading Astronomy popularizer, Jack Horkhimer. whose PBS >> late night shows always ended with the phrase " and remember Keep Looking >> Up". >> At the time I was rudely awakened to reality by the List, and introduced >> to "Noise" >> But Francis, the joy of the experience for me and my school kids was real >> and has remained vivid today. So the persuit is enough to provide lasting >> entusiasm and lifelong interest in the subject. >> I have a question. >> Would the Noise material contain Ni? >> If the pollutants are from manufacturing in say China [not much in the >> USA anymore], would the processing of the material reduce the metal to >> Fe? >> If that were the case a simple test for Ni might be a step toward >> separatng vast amounts of noise from more potentially meteoric stuff. >> Jerry Flaherty >> ----- Original Message ----- >> From: "mexicodoug" <mexicodoug at aol.com> >> To: "Francis Graham" <francisgraham at rocketmail.com>; >> <meteorite-list at meteoritecentral.com> >> Sent: Tuesday, November 20, 2007 1:29 PM >> Subject: Re: [meteorite-list] Brownlees in Rainwater >> >> >>> Hello Francis, Chris, Larry and other hip, enthusiastic educators or >>> Listees, >>> >>> Thanks again for the interesting subject, and also to Chris who got a >>> late but great reply in there... >>> >>> Francis' has hit upon a subject on classroom study of the micrometeorite >>> question is really a way to get students close and personal with >>> meteorites in the most delightful way - a memorable educational >>> experience. I know everyone has special needs for their particular >>> science class curriculum, but I wanted to add a P.S. with some links >>> just suggesting you take a look at what has been done by Lepidopterists >>> to stimulate scientific minds in North America in their field. The >>> study of butterflies, skippers and moths is really not a popular subject >>> in schools; Unfortunately, even keeping hard-core scientific groups >>> related to it alive is sometimes a challenge. In a stark contrast, The >>> Monarch Watch Program, between Canada, the U.S., and Mexico has proved >>> to be an engine for young minds and is popular year after year; a very >>> memorable experience for aspiring student biologists. Not to mention the >>> appreciation and culture it leaves all participants for the subject >>> matter. >>> >>> I'm very biased in applying this to your "problem" (in a scientific >>> sense, of course) since my other love is as an amateur enthusiast of >>> Lepidopterology, and have had personal contact with the leaders, but >>> have no part in organizing, this remarkable success. Scientists alone >>> needed help if they could ever draw any conclusions, and this was needed >>> at a local level. Who would have thought 15 years later the program is >>> stronger than ever, self-funded and still making news even in the local >>> papers in Mexico, with young scientist delighting in the opportunity to >>> be essential contributers to science and develop their scientific >>> curiosity in biology by direct participation and contact with the >>> natural sciences? Two thousand educational organizations are involved >>> and it is estimated that 100,000 students annually have the joy of >>> participation, doing science, and having exciting field expeditions. >>> >>> The thought that bulk analyses could be made of hypothesized meteoritic >>> materials sampled over greatly varying geography but standard protocol >>> seems to put statistics in our favor of separating the noise from the >>> micrometeorites that form a portion of the fallout. >>> >>> OK, sorry for maybe going overboard with a second post - here are some >>> pertinent links you are cordially invited to click: >>> >>> The classic: http://www.monarchwatch.org/tagmig/tag.htm >>> More really interesting stuff IMO: >>> http://www.monarchwatch.org/class/studproj/vector.htm >>> http://www.monarchwatch.org/class/studproj/hiso.htm >>> http://www.monarchwatch.org/class/studproj/mass.htm >>> >>> Best wishes and Great Health, >>> Doug >>> >>> >>> >>> >>> >>> >>> ----- Original Message ----- >>> From: "Francis Graham" <francisgraham at rocketmail.com> >>> To: <meteorite-list at meteoritecentral.com> >>> Sent: Tuesday, November 20, 2007 11:42 AM >>> Subject: Re: [meteorite-list] Brownlees in Rainwater >>> >>> >>>> Dear Doug, Larry and List, >>>> Thanks for the response from you both and from Sr >>>> Gallo in Venezuela! Upon further reflection, I am not >>>> sure how much information can be gained from >>>> micrometeorite lunar dust grains...the problem is that >>>> you have only one or two mineral grains...maybe three. >>>> But what you lack in macroscopic petrological context, >>>> you might gain in microscopic studies involving >>>> isotopes, studies of polymorphic forms, and odd >>>> minerals (e.g. Hapkeite) etc. >>>> But then there is the whole problem of >>>> identification of lunar micrometeorites, not an easy >>>> one to solve, especially, as Larry says (and I agree) >>>> they are likely to be rare. >>>> Hmmmm. I like your suggestion that this would be an >>>> interesting project to critically examine, in >>>> conjunction with an educational project. >>>> >>>> Francis Graham >>>> >>>> >>>> --- mexicodoug <mexicodoug at aol.com> wrote: >>>> >>>>> Dear Francis, >>>>> >>>>> I was thinking exactly the same angle already posted >>>>> by Larry, so let me >>>>> just comment on your question: >>>>> >>>>> "And at what size level does a meteorite cease to be >>>>> of interest?" >>>>> >>>>> by offering the opinion: >>>>> At the level it ceases to contain any information >>>>> attributable to >>>>> meteoroids, meteorites or their parent bodies. >>>>> Since this will change with >>>>> time and technology, the question may be time and >>>>> resource dependent. >>>>> However, your inquiry about whether any of these >>>>> particles have been >>>>> analyzed (or imo, capable of being analyzed at >>>>> present), stands. >>>>> >>>>> It would seem to me, that a very good project for >>>>> schools would be to >>>>> organize a collection protocol for educators in the >>>>> style of the superb >>>>> International Monarch Butterfly tagging program (or >>>>> also like SETI on home >>>>> computers), to collect large amounts of this >>>>> material, set up a factorial >>>>> experimental design to test certain hypothesis and >>>>> bulk sample differences, >>>>> by appropriately submitting these for testing. >>>>> >>>>> I would imagine that this is an experiment that >>>>> neither the ESA nor NASA >>>>> have the resources nor mandate to do, yet could lead >>>>> to profound insight on >>>>> the nature of cometary particles on Earth and make a >>>>> very good contribution >>>>> to science by enthusiastic young scientsits to be. >>>>> Or I darkly suspect, >>>>> more likely an application of the scientific method >>>>> to disprove a popularly >>>>> held theory theory regarding most of the materials >>>>> recovered in this way - >>>>> either way, a great exercise for teaching meteorites >>>>> and science in general >>>>> with a problem, methodology, and a participative >>>>> attitude. >>>>> >>>>> Surely there is some work on this out there, but >>>>> sample size and scope >>>>> restrictions make this an ideal educator's project >>>>> looking only for someone >>>>> like you to organize. Just need a partner in the >>>>> scientific community >>>>> willing to lead in the intrumental analyses and >>>>> sample preparation. >>>>> >>>>> Best Wishes and Good Health, >>>>> Doug >>>>> >>>>> >>>>> >>>>> ----- Original Message ----- >>>>> From: <lebofsky at lpl.arizona.edu> >>>>> To: "Francis Graham" <francisgraham at rocketmail.com> >>>>> Cc: <meteorite-list at meteoritecentral.com> >>>>> Sent: Tuesday, November 20, 2007 8:49 AM >>>>> Subject: Re: [meteorite-list] Brownlees in Rainwater >>>>> >>>>> >>>>> > Hello Francis: >>>>> > >>>>> > I do not pretend to be an expert on this subject, >>>>> but the simple answer to >>>>> > at least oneof your questions is that there is no >>>>> indication that any of >>>>> > the micrometeorites (and thus what you might get >>>>> in rainwater) is >>>>> > planetary or lunar. The ones collected in the >>>>> upper atmosphere are either >>>>> > from asteroids or comets. It may be that some very >>>>> small percentage is >>>>> > planetary/lunar, but these might be so rare as to >>>>> be lost in the noise. >>>>> > >>>>> > Larry Lebofsky >>>>> > >>>>> > On Tue, November 20, 2007 7:31 am, Francis Graham >>>>> wrote: >>>>> >> Dear List >>>>> >> I have a question which has been vexing me for >>>>> some >>>>> >> years. I was introduced to a method of collection >>>>> of >>>>> >> micrometeorites by Larry Megahan some years ago, >>>>> which consisted of >>>>> >> collecting rainwater and then wrapping a powerful >>>>> rare Earth magnet in >>>>> >> Saran (TM)wrap. Placing >>>>> >> the Saran wrap on a glass plate, and examining it >>>>> under the microscope, >>>>> >> one >>>>> >> could see many ferromagnetic particles. Some were >>>>> rounded and ablated and >>>>> >> it was a strong guess that these were >>>>> micrometeorites. I have had some >>>>> >> students try this project and indeed some of the >>>>> particles are >>>>> >> microspheroids of ablated iron, similar to so >>>>> called "Brownlee particles" >>>>> >> colected in the stratosphere. But I have reason >>>>> to be suspicious, >>>>> >> especially if the collection is near a former >>>>> industrial or mining site. >>>>> >> MY >>>>> >> QUESTION IS, has this method, widely circulated >>>>> >> in presecondary teaching circles, ever been >>>>> critically evaluated by >>>>> >> electron microprobe analysis, X-Ray fluorescence >>>>> or some such? And at >>>>> >> what >>>>> >> size level does a meteorite cease to be of >>>>> interest? It would naively >>>>> >> seem, >>>>> >> that although a very very very tiny percentage of >>>>> meteorites are lunars >>>>> >> or >>>>> >> Martians, if a way to rapidly identify >>>>> micrometeorites >>>>> >> can be done, a lot more information on Mars and >>>>> the Moon could be >>>>> >> obtained, >>>>> >> simply because there are so many micrometeorites. >>>>> This would include >>>>> >> collection in the stratosphere as Brownlee did, >>>>> maybe piggybacked on >>>>> >> surveillance aircraft. But one question at a >>>>> time. >>>>> >> Francis Graham >>>>> >> >>>>> >> >>>>> >> >>>>> >> >>>>> >> >>>>> >>>> _________________________________________________________________________ >>>>> >> ___________ >>>>> >> Be a better pen pal. >>>>> >> Text or chat with friends inside Yahoo! Mail. See >>>>> how. >>>>> >> http://overview.mail.yahoo.com/ >>>>> >> ______________________________________________ >>>>> >> http://www.meteoritecentral.com >>>>> >> Meteorite-list mailing list >>>>> >> Meteorite-list at meteoritecentral.com >>>>> >> >>>>> >>>> http://six.pairlist.net/mailman/listinfo/meteorite-list >>>>> >> >>>>> >> >>>>> > >>>>> > >>>>> > ______________________________________________ >>>>> > http://www.meteoritecentral.com >>>>> > Meteorite-list mailing list >>>>> > Meteorite-list at meteoritecentral.com >>>>> > >>>>> >>>> http://six.pairlist.net/mailman/listinfo/meteorite-list >>>>> > >>>>> >>>>> >>>> >>>> >>>> >>>> >>>> ____________________________________________________________________________________ >>>> Get easy, one-click access to your favorites. >>>> Make Yahoo! your homepage. >>>> http://www.yahoo.com/r/hs >>>> ______________________________________________ >>>> http://www.meteoritecentral.com >>>> Meteorite-list mailing list >>>> Meteorite-list at meteoritecentral.com >>>> http://six.pairlist.net/mailman/listinfo/meteorite-list >>>> >>> >>> ______________________________________________ >>> http://www.meteoritecentral.com >>> Meteorite-list mailing list >>> Meteorite-list at meteoritecentral.com >>> http://six.pairlist.net/mailman/listinfo/meteorite-list >> >> > Received on Tue 20 Nov 2007 09:12:20 PM PST |
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