From: spike66 (spike66@attbi.com)
Date: Sat Jun 15 2002 - 23:34:20 MDT
Today I discovered what I believe is the cause of the
unexplained shadow Mike Lorrey saw. While out
hiking today, I could see across a big open valley
at least 4 km. It was a crystal clear sunny day, shortly
before noon when a shadow passed, not directly over
but nearby. The shadow had no sharp boundaries,
was not the shape of anything, just a kind of darkened
area.
I saw the shadow race across this open valley so I
could estimate its direction. I looked up but could see
nothing for some time. I knew some large object
had passed in front of the sun and I knew its approximate
speed and distance. About 10 seconds after I noticed the
shadow, I was able to spot a plane, which I was able
to identify as a 747, headed for landing at San Francisco.
It surprised me that the plane was so difficult to spot
even tho I knew about where it had to be. There was
no noise, no contrail, just a silver plane against a blue
sky. I would never have spotted it without the additional
information provided by the shadow.
I think a 747 is about 70 meters in length, so if it were
on approach, 7 km altitude, its fusilage would span the
apparent diameter of the sun. An observer directly in
the path of that shadow would see the sun about 30%
eclipsed, were she able to snap a photo just as the
plane passed in front of the sun.
Mike, could the shadow you saw have been caused by
a 747 on approach to landing in New York? spike
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