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    My First Lunar
    From: David Pike
    Date: 2014 Nov 6, 00:46 -0800


    Last night I shot my first lunar and proved UTC is out by 8 minutes 49 seconds.  Do you think I ought to warn the Authorities? 


    It was a bit of a cheat really.  I was using newly bought Navigator 6.0.1 software, and I knew I was at 53.10N 000.32W, so I used theoretical heights for the Moon and Aldebaran for the corrections.  I also managed to do it all through my lounge window (refraction not corrected for), so I was nice and warm.  On the other hand, it was Nov 5th, Bonfire Night in the UK, and the sky was full of smoke so Aldebaran was barely visible.  Easy to identify though; it was the only star I could see.  It’s possible the far limb of the moon was the wrong one to shoot.  The moon’s almost full at the moment but not quite.


    Steady for Astro




    Sextant: Hughes Mate's Three Circle 1941 No: 25410


    ++ Lunar calculation -Aldebaran-Moon


    + inputs:


    date=  5/11/2014


    watch time= 21:14:54 GMT


    IC= 0.0'  (index correction)


    + sextant readings:


    hs Aldebaran= 27°28.9'


    hs Moon= 41°54.3'


    ds Aldebaran-Moon= 40°36.2'    (sextant distance)




    + corrections


    obj1: Aldebaran


    ha = 27°28.9'


     parlx= 0.0'


     refr =-1.9'


     (c_Aldebaran= 1.9'  refr+parlx)


    hc = 27°30.8'




    obj2: Moon




       + 0.2' (moon disc augmentation)




    Lower limb for Moon


    ha = 42°10.7'




     refr =-1.1'


     (c_Moon=-42.9'  refr+parlx)


    hc = 42°53.5'




    Far limb for Moon




    da = 40°19.8'  (apparent dist.- corr. for IC & SDs)




    +refraction and parallax projection factors


    A=0.5722 (Aldebaran)


    B=-0.1200 (Moon)


    Q= 0.3'  (moon quadratic correction)




    + results


    dc = 40°26.4'  (cleared distance)




    + lunar time determination


    linear interpolation 1 (1 hour interval)


    NA dist @ 21:00:00   = 40°30.0'


    NA dist @ 22:00:00   = 39°54.7'


    Lunar Time = 21:06:05  GMT




    linear interpolation 2 (5 minute interval)


    NA dist @ 21:05:00   = 40°27.0'


    NA dist @ 21:10:00   = 40°24.1'


    Lunar Time = 21:06:05  GMT




    time difference =  0:08:49    (=watch-lunar)


    longitude error =  2°12.2'+


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