Re: Geometry of flashes, Was:Geosynch Flasher seen in Colorado

Bjoern Gimle (b_gimle@algonet.se)
Tue, 1 Oct 1996 00:19:19 +0200 (MET DST)

Robert Sheaffer answered Ron (Lee?): 
>
>>> I still do not understand why an event that is probably tied to 
>>> specific viewer-satellite-sun orientation should occur at the same
>>> time for viewers about 16 degrees apart in longitude.  I am at 104.56
>>> degrees west, latitude 38.9478, 2073 meters, (UT-6).
>>> 
>>> If someone can educate me on why this happens, please do so.
>>
>Me, too. I'm as puzzled as Ron is!
>
>Somebody has gotta figure out the geometry of this thing.
>
I can't answer the questions about visibility in other places
(generally the distribution of a flash is an intersection of a cone
with Earth's 'sphere'), but to me it is almost obvious that, 
in a star-fixed coordinate system :

The Sun-satellite line changes less than 1 degree/day.

The axis of a spinning satellite probably changes less than a degree/day.

If you can observe the satellite in the same celestial surroundings
as another flash observer, you have the same geometry.
(unless the satellite is Earth/gravity stabilized)


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