[meteorite-list] bubbly tektites

From: Graham Christensen <majorvoltage_at_meteoritecentral.com>
Date: Thu Apr 22 09:55:51 2004
Message-ID: <F20sLqIfQdmEB4HGXAw000097ec_at_hotmail.com>

Hello Astro list and meteorite list,

I discovered a few months ago as I was examining my tektite collection that
one of the regular $5.00 pieces that you get from rock shops (indochinite?)
has a bubble in it. The bubble is about 1 mm indiameter. Is a bubble like
this rare? The tektite is an odd looking thing with huge pits (big enough to
stick your finger in) on one side, and a light frothy texture on the other
side.

I have heard of bubbles in tektites before in an article I read somewhere.
It said that the bubbles contain rarified ordinary air. If I remember
correctly, this is believed to have resulted from the tektites forming in a
column of low pressure air trailing the impacting meteorite. But wouldn't
the low pressure air trailing the meteorite be dragged down from the upper
atmosphere which has a different composition? I came up with a crazy
alternative theory (I come up with a lot of these, too much spare time) that
may eliminate this problem:

In grade four, my teacher gave a science demonstration. She placed a metal
container onto a hot plate, this heated the container and the air inside.
Then she but a lid on the container and removed it from the heat source. As
the air cooled it contracted, resulting in a lower pressure, the container
collapsed. So, if a tektite solidified, somewhere under 2000 degrees, with a
bubble in it, the air in the bubble would be at about 2000 degrees. Once the
tektite solidified the air would be trapped in a bubble whose volume could
no longer change. The air would still be at about 1500 degrees and when it
cooled it would contract resulting in a low pressure within the bubble. Am I
on to something or am I just crazy?

************************************************************
Graham Christensen
majorvoltage_at_hotmail.com
http://www.geocities.com/aerolitehunter

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Received on Fri 25 Jan 2002 03:40:41 PM PST