Hi, I need help finding some equations for changing
between coordinate systems.  Specifically, given the
hour angle of the sun (where 0 degrees is high noon),
my latitude, and the sun's declination, I wish to find
the sun's azimuth and elevation.

Other questions:

1.  Is elevation the same thing as altitude, i.e. the
angle between the sun and the horizon?

2.  Is the calculation for azimuth the same one I've
been using for drawing hour lines on horizontal dials,
i.e. D = arctan( tan HA * sin LAT ) ?

3.  Have I used the term "hour angle" correctly?  A
negative hour angle would mean it's morning, a
positive HA would mean afternoon, and HA=0 means the
sun lies in the observer's meridian.

Thanks in advance,

Rod Heil
41 18 41 N  x  105 35 26 W

Reply via email to