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    Re: A lunar in 1845
    From: Ed Popko
    Date: 2019 Jan 4, 05:57 -0800

    Frank, I need some help with your Halloween: Lunars: altitude accuracy and the 90 degree miracle you referenced. In rerunning an old lunar with a distance near 90 degrees, I get strange results. Below is the best lunar I have shot with an LD near 90 degrees. After clearing etc. it resulted in a GMT 16 seconds fast from the actual time taken. I got lucky.

    Below is my Moon-Aldebaran data.  Where I have trouble is retrofitting this sight in the altitude accuracy equations to see how little influence the moon's altitude would have had  though I did take altitudes for this shot. Your web calculator did it for me.  I'm just curious to see what altitude leeway I would have had.

    Any help appreciated.  My guess is it is a units problem and also that the moon accuracty equation goes to infinity as it approaches an LD of 90 degrees. 

    My best moon-Aldebaran lunar with a LD near 90 degrees using the Reed web calculator:

    KP=28°41.1'N 082°18.2'W
    Dec 24, 2017 moon-Aldabaran (far) 
    GMT of observation 00:05:54


      Moon                  
       HaMoon    37°50.1'   
       Alt Cor     -42.8'   
      Body                  
       HaBody     36°10.7'  
       Alt Cor       01.3'  
      LDa         95°53.6'
     
      >HP            55.19'   

      >LDc        95°04.5'  Cleared 
      >%Change       -0.85  % difference Pre-cleared -> cleared 
      >delZcos       -0.706         
      >delZ         136.2°  
                            
    GMT from Lunar Observation
      00:00:00  95°07.7'  Almanac bracket
      00:06:15  95°04.5   Computed time from LDc
      03:00:00  93°35.6'  Almanac bracket


    GMT Summary
     --------------------                
     LDo           00:05:54  Actual GMT of observation
     LDc           00:06:15  Calculation GMT from LD observation
     Difference 00:00:21  LD calculated GMT was fast 21 seconds


    Accuracy Required minutes of arc
    Moon: ? -86 <----------------------------------  PROBLEM HERE
    Body: 7'
      


       
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