Ex25-2 Determine the azimuth of the sun having declination 8° 24' S during sunset at Roorkee (latitude 29° 52' N).
Figure Example 25-2 (a)
Solution :
Given, latitude of observer, f = 29° 52'
declinationof the sun, d = 8° 24' S
The Sun at sunset, thus altitude a = 0°
Therefore f = 90°
z = 90° + d = 98° 24'
s = 90° - f = 60° 08'
Figure Example 25-2 (b)
The triangle ZPS is a right angled astronomical triangle, where RZ (in ZPS) is in western hemisphere.
Now, using equation 25A.3a, we get
= - 0.168
Z = 99° 41' 53".07 (W)
Thus, azimuth of the sun, A = 360° - Z = 261° 59' 32".26