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    Re: Sun Moon Lunars to 155 degrees
    From: George Huxtable
    Date: 2010 Apr 2, 09:35 +0100

    Brad Morris wrote-
    > Finally the calculator states an error of 3.8 minutes in Moon altitude
    > and 3.4 minutes in the Sun's altitude. In attempting to use 3.6 minutes
    > as an index correction, it is shown that the error in alitudes are in
    > opposite directions.
    > Best Regards
    > Brad
    
    and Bill Noyce responded-
    
    Perhaps that supports the idea that the altitudes were measured 
    simultaneously with the lunar distance, using two separate octants?
      -- Bill N.
    
    ========
    
    I don't really agree with any of that.
    
    Remember, lunar-distance is an inexact science, and there's plenty of scope 
    for scatter in the result.
    
    In this case, the lunar distance being so large, the Moon and Sun are both 
    low in the sky; one to the East, and rising (this being from the tropics) 
    at about 15º per hour, the other falling in the West at a similar rate. Any 
    error in predicted GMT from the lunar will put one higher, and the other 
    correspondingly lower. So any discrepany between the calculated altitudes 
    tells us little about the errors in observing those altitudes.
    
    George.
    
    contact George Huxtable, at  george{at}hux.me.uk
    or at +44 1865 820222 (from UK, 01865 820222)
    or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
    
    
    
    

       
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