Sight Reduction

This page allows you to compute sight reductions. As an example try entering this example from the text. L= 26.108333 S. Note that the minutes and seconds must be changed to decimal as done here. D=29.031666 N. H=44.966667 E. The result z is 70.005186639 (70° 0.3111´) and Hc = 19.994813360 (19° 59.68´). P is 60.968334 (60° 58.10´) and Z is 41.112069600 (41° 6.724´). The degrees and minutes input isn't working yet but the output is displayed in decimal and degrees and minutes.

1. Enter your Latitude (L)
2. Enter the Declination of the body (D)
3. Enter the Hour Angle of the body (LHA or t)
4. Zenith Distance (z)
5. Calculated Altitude Hc ( = 90-z )
6. P Polar Distance (co-D) of body
7. Z azimuth angle of body (interior)
8. Zn azimuth angle of body (from true north)