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Re: Query about solar azimuth formula



I see that Paul's Sun Altitude agrees with Margaret's.
But his Sun Azimuth does not account for time of day.
Perhaps a term is missing?

Brian

At 10:05 11/3/97 EST, Paul Camp wrote:
This is the coordinate system transformation taken from Peter
Duffet-Smith's book Practical Astronomy with your Calculator. To go
from equatorial to horizon coordinates:

sinA = sinD sinL + cosD cosL cosh
cosB = (sinD - sinL sinA)/(cosL cosA

This gives you both solar altitude and solar azimuth (I think I
translated from Duffet-Smith's notation correctly)

Paul J. Camp

[Margaret]
calculate A from -

sinA = sinLsinD + cosLcosDcosh

where L = latitude of observer
D = solar declination
h = solar hour angle = (t-12) x pi/12 (in radians)
and t = mean solar time in hours.


(1) B = -arcsin(-cosDsinh/cosA)
------------------------------------------------------------


brian whatcott <inet@intellisys.net>
Altus OK