[meteorite-list] Brownlees in Rainwater
Jerry
grf2 at verizon.net
Tue Nov 20 21:12:20 EST 2007
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
>>>>> >>
>>>>> >>
>>>>> >>
>>>>> >>
>>>>> >>
>>>>>
>>>> _________________________________________________________________________
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>>>>> >> ______________________________________________
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>>>>> >>
>>>>>
>>>> http://six.pairlist.net/mailman/listinfo/meteorite-list
>>>>> >>
>>>>> >>
>>>>> >
>>>>> >
>>>>> > ______________________________________________
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>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>>
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