(meteorobs) Identifying Micrometeorites

[Wayne Watson]

Hi, yep, I've gone through the scouring gutters, dragging magnets, etc. I
invited a guest speaker to one of our museum public gatherings on astronomy
last weekend, and presented some yet unidentified specimens with a 40X 
microscope to the audience after the speaker. I thought it would be just a 
quick item, but people really wanted to know how to collect them. It was 
good fun.

I'd love to provide the photos, but I found that my camera to eyepiece 
adapter, 1.25", won't fit in the EP of a microscope, 1.2", I believe. Next 
week I may video them with my buddy's video camera that attaches to his scope.

Eventually, I'll likely send it off to NM for analysis. It takes about 3 
months. In the meantime, we can act like scientists with what we have at hand.

mark ford wrote:

> 
> I've done this myself, dragging a magnet (in a plastic bag) through
> gutters and evaporated rainwater containers. With mixed results.
> 
> The technique is discussed here : 
> http://www.kyes-world.com/micrometeorites.htm
> 
> 
> There are so many terrestrial contaminants that look the part, the only
> way to be sure is under a powerful microscope or microprobe type
> analysis.
> 
> 
> I'd love to see some photo's.
> 
> The fact that they are concentrated in one place might mean there is a
> terrestrial source such as a rusting roof antenna bracket dropping rust
> grains into the rain water for example.
> 
> 
> 
> 
> Best
> 
> Mark Ford
> 
> 
> -----Original Message----- From: Wayne Watson
> [mailto:sierra_mtnview at earthlink.net] Sent: Wednesday, February 09, 2005
> 11:54 AM To: meteorobs at meteorobs.org Subject: (meteorobs) Identifying
> Micrometeorites
> 
> A young student brought some metal particles into a friend's science
> class last week that he and his grandfather had collected from a gutter.
> After putting the samples under a microscope, there were many that had
> the spherical shape one would expect of a micrometeorite. So my friend
> and I thought we'd try our hand at it and tried two other sources,
> nearby buildings. We found some but not nearly as many as the student's
> efforts. It seems a bit odd that the distribution would be skewed to one
> location. However, it may be explainable.
> 
> It's quite possible that what we are seeing might be something else, for
>  example, beads from welding. If we continue to find similar beads, then
> it seems less likely the material is from welding. Is there an easy way
> to identify them as meteoric in origin? I have one way of doing this,
> and that is to send them to a meteorite lab in New Mexico. However, I'm
> wondering if there's a simple test for them?
> 
> While I'm at it, I'll ask if there is an adapter that I can get for a
> SLR that allows me to attach my camera to a microscope. I tried using my
>  SLR/eyepiece adapter to the teacher's microscope, but the barrel is 
> probably 1.2" in diameter. Just a little too small.

-- 
              Wayne T. Watson (Watson Adventures, Prop., Nevada City, CA)
                  (121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
                   Obz Site:  39° 15' 7" N, 121° 2' 32" W, 2700 feet

                         Web Page: <home.earthlink.net/~mtnviews>