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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Longhand Sight Reduction
From: Greg Rudzinski
Date: 2014 Nov 8, 18:25 -0800
From: Greg Rudzinski
Date: 2014 Nov 8, 18:25 -0800
Francis,
Here is an example from this afternoon for you.
L= Latitude
d= Declination
LHA= Local Hour Angle or Meridian Angle
P= Product
hv= Haversine
hv(-1)= Arc Haversine
ZD= Zenith Distance
Hc= Calculated Altitude= (90°-ZD)
Reduction sequence for latitude and declination contrary in name:
Column A: hv(L+d) + hv(L-d)= sum. (1-sum) x hv(LHA)= P
Column B: hv(L+d) + P = sum. Arc hv(sum)= ZD. 90°-ZD= Hc
Greg Rudzinski