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Lunar intercept method
From: Doug Royer
Date: 2003 Jun 16, 11:52 -0700
From: Doug Royer
Date: 2003 Jun 16, 11:52 -0700
I tried this 2 times and here are the results for what they are worth.I took as much care in the takeing the alts as possible.All alts and times of the bodies are averaged from 3 cuts each.I used Fred Hebard's suggestion of checking Ie useing the semidiameter of the Moon.Ie remains 0.1' off arc through out.I will provide the reduction data for the each 3 star fix if asked.All are reflected altitudes.The procedure is simple to do and if I understand and used the formuli from chapter 7 correctly the results are interesting.The final results taken from raw data took about 20 min. to complete.GPS pos = 32*49.4'N,116*49.8'W.All times are zd - 7. 06-14-03, 60*F, 27.7' Hg.The 3 stars used are Antares 220449,Vega 220614,Spica 220833. The 220833 3 SF pos = 32*49.2'N,116*47.8'W which is also the AP for the Lunar LOP. Lunar LOP = upper limb 231709 Hs= 21*38.0' , Ho=22*15.3', Hc=21*15.6', I=0.3mA, Zn=146.7*,dec=26*23.4S,GHA=82*12.7',LHA=325*24.9' N.A. data 0600 gmt 06-15-03:v=7.81,d=9.37 Useing the formuli from chapter 7 for f,delta T" and C' f=-1.8549,delta T"=7.3552 slow,C'=1.8438' or 1' 51" Chrono=7.4 sec. slow. Final long=AP long + C'=116*49.7'W. final pos=32*49.2'N,116*49.7'W 06-15-03,55*F,27.7' Hg,stars are Altair 231222,Deneb 231503,Spica 231759.The 231759 SF and AP=32*49.44'N,116*49.48'W. Lunar LOP=upper limb 235657 Hs=19*11.2',Ho=19*48.6',Hc=19*48.8',I=0.2mA,Zn=141.9*,dec=26*00.2'S,GHA=76*3 5.6',LHA=319*46.1' N.A. data 0600 gmt 06-16-03:v=9.20,d=11.92 f=-1.5752,delta T"=3.5483 slow,C'=0.8895' or 53" Chrono=3.6 sec. slow.Final long=AP long + C'=116*49.48'W + 53"=116*50.37'W.final pos=32*49.44'N,116*50.37'W Please critique.