[meteorite-list] "Gravitational focusing"
From: Starbits_at_aol.com <Starbits_at_meteoritecentral.com>
Date: Thu Apr 22 09:37:32 2004 Message-ID: <fb.eb754d8.275f3fd9_at_aol.com> In a message dated 05-Dec-00 6:51:04 PM Pacific Standard Time, ROBERT.D.MATSON_at_saic.com writes: << An additional related point: what are the sizes and geographical shapes of tektite "strewn fields"? Unless they are highly elliptical, covering hundreds of kilometers in the long-axis, I would have to pretty much rule out a lunar origin just from an orbital dynamics standpoint. >> Hello Rob I agreed with what you said up to this point. The tektite strewn fields do cover hundreds of kilometers and even 1000+ kilometers in long-axis. However orbital mechanics still does not allow a lunar origin based upon strewn field size. A lunar eruption would either blow out a single chunk or a spray of lunar ejecta. A single chunk would enter like a meteorite and would have a similar strewn field pattern. As far as I know the smallest tektite strewn field is larger than the largest stone meteorite strewn field. A spray, even from a volcanic cone with a extremely narrow cone of 1 degree spread, would expand to 5000 miles across by the time it reached earth on a direct straight shot. Entry into the atmosphere would increase this significantly because not all particles would enter at the same time even for a staight shot (imagine a ruler approaching a basketball). Any kind of off line or orbital path would just increase the effect causing a wider spread. Even a direct staight line shot spread of 5000+ miles exceeds the long-axis of most if not all tektite strewn fields. The lunar volcano theory either produces strewn fields that are too large or too small, but never just right. Eric Olson http://www.star-bits.com Received on Wed 06 Dec 2000 02:08:09 AM PST |
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