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Re: Exercise #12 Daylight Sun/Moon Fix
From: Jeremy C
Date: 2008 Jun 8, 02:43 -0700
From: Jeremy C
Date: 2008 Jun 8, 02:43 -0700
Solution: I reduced this fix in several ways but I will review two of them here. The first was to take all of the lines and reduce them via computer software to get a position. The second was to average both the times and altitudes of the moon, and reduce that average moon line along with the sunline to get a regular running fix. For these lines I used the assumed position method and HO 229 Volume 1. The computer print out is photographed and attached as a jpg file for people to look at in my next post. The position the computer gave me was Latitude 14 deg 36.4� North and 145deg 18.4�E. This gives an error of about 1.5 miles from the GPS fix. The tabular reductions using no calculator, is as follows: Moon UL Hs 72deg 26.0� Dip -9.9� Ha 72 deg 16.1� Body +27.9� HP (57.6) +3.6� UL corr -30.0 Ho 72deg 17.6� This is different from the computer for some reason that I do not know. UTC: 21h 00m 53s on 28 May 2008 GHA hr 214deg 30.4� Tcorr 12.6� Vcorr (13.8) 0.1� GHA 214deg 43.1� +aLong 145deg 16.9� LHA 000deg Assumed Lat 15deg N Dec hr S 3deg 05.7� Dcorr (-15.4) -0.1� Dec S 3deg 05.6� Dec incr 5.6 D -60� Corr -5.6 Hc-t 72deg 00.0� Hc 71deg 54.4� Ho 72deg 17.6� A 23.2 Towards Zn 180 Sun LL Hs 16deg 43.1� Dip -9.9� Ha 16 deg 33.2 Body 13.1 T/P 0.2 Ho 16 deg 46.5� UTC 21h 06m 15s 28 May 2008 GHA hr 135deg 39.6� Tco 1deg 33.8� GHA 137deg 13.4� +aLong 145deg 46.6� LHA 283deg Assumed Lat 15deg N Dec hr N 21deg 37.5� Dcorr (+.4) 0.0 Dec N 21deg 37.5� Dincr 37.5 D +10.2 Corr +6.4 (equals 37.5*10.2/60 or (dec incr * D)/60 or use the tables on the inside covers of HO 229) Hc-t 17deg 11.6� Hc 17deg 18.0� Ho 16 deg 46.5� A 31.5 Away from Zn 072.2 deg. Jeremy --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---
