Hello List, Rob wrote in part ; "meteorite-dropping". I was not sure and was always to afraid to ask, but now I know that they do. I was finding little globs on the bottom of my display case and attributed to my rusting Nantan. Know that I know what it really is, I will use kitty litter on the bottom of my case! Thanks for bringing this up Rob. : ) Thanks, Tom Peregrineflier <>< The proudest member of the IMCA 6168 ----- Original Message ----- From: Matson, Robert <[EMAIL PROTECTED]> To: 'tracy latimer' <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]> Sent: Friday, August 08, 2003 7:26 PM Subject: [meteorite-list] Determining fall rate from falls observed
> Hi All, > > Tracy asked: > > > Considering that there has been a scientific presence on > > the Antarctic ice cap for the past 30+ years, a good place > > to start might be: How many witnessed falls are there > > from Antarctica? > > I would guess none. The greatest human presence is during > austral summers, when you have perpetual daylight, so only > the very brightest bolides would be noticed. More importantly, > the only large concentration of people is at McMurdo, so the > only falls likely to be seen would be within a couple hundred > miles of McMurdo. > > Only a very small fraction of earth's meteorite falls are > observed. Ignoring the ~70% that are missed because they > occur over the ocean, you still have vast regions of earth's > land mass that are very thinly populated (Gobi and Sahara > Deserts, Greenland, northern Canada, Australian outback, > Siberia, etc.) Factor in the % of time that people are > outdoors, the probability of clear skies, and account for > areas with very obscured viewing (e.g. forests), and I bet > you're left with a number less than 1%. > > It also wouldn't surprise me if a significant fraction of > meteorite-dropping falls were not only unobserved but > unobservable. No one is going to see a magnitude -4 bolide > in broad daylight, and yet this might be all that you could > hope for from a tiny stone of a gram or two. > > --Rob > > ______________________________________________ > Meteorite-list mailing list > [EMAIL PROTECTED] > http://www.pairlist.net/mailman/listinfo/meteorite-list > ______________________________________________ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list