| MadSci Network: Astronomy |
Hmmmmm... an interesting idea! Would it work though? I would have to agree with Dr. Brownlee - I doubt it. The reason is that small particulate matter is raining down on us all of the time from industrial sources, forest fires, volcanic eruptions, automobile exhaust (and trucks!), road dirt, and a variety of other sources. The only way to demonstrate that these micron sized particles are extra-terrestrial in origin is by analysis of the isotope ratios and demonstrating that the compositions do not match known terrestrial sources. A Scanning Electron Microscope with EDAX will give a rough composition but will not give isotope analysis. To do this, you would need an Stable Isotope Ratio Mass Spectrometer and individual micron particles to analyze. That would mean sorting out "dust" for single grains in order to analyze them - which, I would submit, is not an easy task!
However, in theory, if you were to look at the local and regional industrial sources, etc., and then compare analyses across a number of regions in the country, you might be able to pick out some trends or such that would be indicative of extra-terrestrial origin.
Having said all that, I think that "the proof is in the pudding". I would suggest that you do the experiment to find out if it can be done!
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