sun angle and azimuth

[Bill Hargrove]

Hello Netters:

     If I have a TM image of Yellowstone Nat'l Park made at 17:40 Greenwich
time on August 2, 1989, how can I calculate the sun's altitude and azimuth?
I want to split the image into well-lighted and shaded areas in order to
get a better image classification of burn severity.  I know the center of
the image, and that it was made at 11:40 AM local time (I think).
     Can anyone point me in the right direction (grin)?
                                   Thanks,
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Bill Hargrove
Oak Ridge National Laboratory
Environmental Sciences Division
P.O. Box 2008, M.S. 6038
Oak Ridge, TN  37831-6038
(615) 574-1902
(615) 576-8646 (fax)
hnw at mtqgrass.esd.ornl.gov
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