NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: David Pike
Date: 2015 Sep 7, 17:30 -0700
and of course if you wan’t something cleverer than a simple latitude shot, you probably need 1998 values to start off with. DaveP
Having spent a fairly futile hour wading through APs 3270, I remembered that several months ago I’d bought a computer programme called Navigator, so I thought I’d check my working against that. The figures for 00.00 Tuesday 8th Sep were as follows:
Aries GHA
Year ddd mm.m
1998 347 50.4
2002 347 52.2
2006 347 54.3
2010 347 56.4
2014 347 58.1
Difference 1998 to 2014 GHA Aries 7.7’, I guesed 6’
Polaris GHA Dec
Year ddd mm.m dd mm.m
1998 310 28.8 89 14.0
2002 309 43.1 89 15.1
2006 308 45.1 89 16.4
2010 307 34.4 89 17.4
2014 306 28.2 89 18.4
Difference 1998 to 2014 GHA Polaris 4° 00.6’ SHA Polaris 3° 52.9’ Dec Polaris 4.4’, a significant difference due to P&N changes. It ougt to be possible to work out a Q Table knowing SHA and Dec Aries for a particular year using polar graph paper, but I'll leave that to the mathematicians
DaveP