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    Re: artificial horizon
    From: George Huxtable
    Date: 2011 Jan 25, 12:17 -0000

    Gary Mickus wrote-
    
    
    On 1/20/11 shooting the sun using a Davis Mark 3 sextant  and Davis
    artificial horizon filled with glycerol with the plate glass wind screens
    obtained Hs lower limb readings which were way too high.  Examples: UTC
    20:41'28" = 76 28', 20:49'30" = 76 20', 20:55'15" = 76 16'.
    
    What could be causing the high readings.?
    
    Thanks,
    
    Gary.
    
    ===================
    
    As we have another Gary, a prolific poster, on this list, it might be a
    good idea if Gary Mickus modified his "handle" in future postings, to be
    something such as "Gary M", or confusion will certainly ensue.
    
    Gary M doesn't tell us his locality, which is essential information to
    allow his question to be answered. But presuming he is not in the tropics,
    or in the Southern Hemisphere, I wonder if he has simply failed to divide
    his reflected angles by 2? Reflecting in a horizontal mirror has the effect
    of doubling the apparent angle. But before dividing, he should first
    correct the observed angle for any index error.
    
    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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