On 28/06/2011 14:06, Col wrote:
wrote in message
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wrote in message
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A bit of Googling (unfortunately most of it's conspiracy theory
nonsense) suggests that this is the answer:
http://contrailscience.com/contrails...es-chemtrails/
I think the "edge shadow (volumetric shadow)" is what I saw,
the contrail was lined up with the sun.

However contrails must be crossing the sun all the time and I've
never seen that effect before. I wonder if you only see it if the
sun is at exactly the right altitude and the observer is in exactly
the right position wrt the sun& contrail.

Yes, read the part of the linked article starting at "[Math Warning]".

It's the part beyond 'Math Warning' that makes my eyes glaze over....

LOL those responses are the ones I read Col.

Aliens, energy beam weapons, and all kinds of weird pseudo science.
It's good for a laugh.

Joe Egginton
Wolverhampton
175m asl