[Rockhounds] CAN YOU REALLY FIND MICROMETEORITES IN YOUR GUTTER? WELL…

[pmodreski at aol.com]

I think you all know this, but just to add, what I've read, is that it's only off an absolutely clean and pristine roof (or other) surface that one could be likely to find and recognize, black magnetic dust specks that are really micrometeorites.  Finding them off any "ordinary" surface, like a roof and in its rain gutters, would be pretty much impossible--they would be totally swamped by the amount of ordinary earth-derived particles (yes, mostly magnetite).  Especially, any roof of the ordinary composition-shingles type, forget it.
Pete


-----Original Message-----
From: Kreigh Tomaszewski <kreigh at gmail.com>
To: Rockhounds at drizzle.com: A mailing list for rock and gem collectors <rockhounds at rockhounds.drizzle.com>
Sent: Sun, May 19, 2019 11:27 am
Subject: Re: [Rockhounds] CAN YOU REALLY FIND MICROMETEORITES IN YOUR GUTTER? WELL…

The black magnetic flecks in sand are almost always magnetite.

On Sun, May 19, 2019 at 11:03 AM THE HAMMER <hammerron at hotmail.com> wrote:

> When I was a kid, I used to drag a magnet across sand and save the small
> black bits attracted by the magnet.  I used to call them iron filings,
> though I do not know if that is the proper term for what I had.  In
> hindsight, I wonder if any of the material could of been meteoritic?
>
> On 5/16/19 5:59 PM, Kreigh Tomaszewski wrote:
> > I collect meteorites <https://www.youtube.com/watch?v=TuDfZ2Md5x8>, and
> > have quite a few knocking around my home office. Some are big —
> fist-sized,
> > with one I bring with me when I give talks about impacts so people can
> hold
> > a piece of an asteroid in their hand — but most are pretty small, like
> the
> > size of a finger from the last joint to the tip. A few are pebbles
> > (generally well-known ones with special scientific interest, making
> bigger
> > pieces hard to obtain), and a couple of are sand-grain-sized (one is from
> > the Moon and the other from Mars).
> >
> > While I don't collect them, there is another kind that’s even smaller:
> > Micrometeorites, usually smaller than a millimeter across, some so teeny
> > you need a microscope to see them clearly. Bigger ones (say, a tenth of a
> > millimeter and up) are usually spherical or close to it, because they
> melt
> > completely as the ram through our atmosphere at hypersonic speeds, then
> > solidify after they've slowed down to subsonic speeds (in fact they
> > probably fall the rest of the way extremely slowly due to their size).
> >
> >
> https://www.syfy.com/syfywire/can-you-really-find-micrometeorites-in-your-gutter-well
> > _______________________________________________