Hi Jim: Interesting question and theory, but kinda from left field on this List, isn't it? Anyway, by coincedence, I may be able to shed some light on your question as I have designed, supervised the tower construction and munitions placement, and detonated a mock atomic explosion, which turned out to be quite a realistic simulation - including the mushroom-shaped cloud. Yep, my contribution to your "universal phenomenon" ! If you would like to learn more about my conventional, nuclear and thermonuclear explosives experiences, please contact me off list. Cheers, Joel P.S. I'm posting this response because a more practical use of my expertise could some day benefit finders such as the guys who discovered the 3+ ton "The Old Woman" meteorite in the Mohave Desert boondocks (ref: pages 252-5, Norton's "Rocks from Space",1st edition).
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- Subject: Why a mushroom cloud?
- From: Jim Hurley <hurleyj@arachnaut.org>
- Date: Thu, 03 Jun 1999 11:58:08 -0700
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I had always wondered why a large explosion tends to produce a mushroom-shaped cloud. At first, I thought it was just something to do with nuclear explosions, but other observations seem to indicate it is a universal phenomenon. I think I understand how it happens: Imagine a large explosion at ground level. To a first approximation assume the earth is uniform in density. In that case the explosion would generate a hemispherical depression in the blast area. Shock waves in the reverse direction, 'bouncing back' from the blast will be focussed due to the hemisphere, exactly like a lens. This would force the ejecta and dust and gases upwards vertically at hypersonic speed where they will rise until slowed down by friction. At that retardation point, the dust and gases would amass to form the mushroom cap. This seems reasonable to me, does anyone know if that is exactly what happens? -- Jim Hurley Freelance graphics artist Web page design; graphics; multimedia <URL: http://www.arachnaut.org/ > ---------- Archives located at: http://www.meteoritecentral.com/list_best.html For help, FAQ's and sub. info. visit: http://www.meteoritecentral.com/mailing_list.html ----------
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