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    Nautical almanac first point of aries
    From: John Doe
    Date: 2012 Mar 12, 11:17 -0700

    Greetings,
    
    I have been looking at the online nautical almanac at
    http://www.tecepe.com.br/scripts/AlmanacPagesISAPI.isa/pages?date=03/12/2012
    
    and for today  monday  12 mar 2012  the GHA angle for aries  is  80
    deg 47.1 min  at  18:00 h  GMT
    
    I think  I can convert the GHA for aries to  time  and that should be the
    same as sidereal time at Greenwich.
    
    (  (80./15) + (47.1/60)/15 ) =  5.38566...
    taking the 5 out and mult the fractional part by 60         .3856666 *
    60 = 23.1399...
    and taking out the 23   and doing the same                    .13999 * 60 = 8.3
    
    I used this web site to get sidereal time at  longitude 0 deg 0 min
    http://tycho.usno.navy.mil/cgi-bin/sidereal-post.sh
    and pressed compute at approx.  16:00:00   GMT
    
    05:23:45.4
    
    
    The seconds are not in close enough agreement which makes me think I am
    missing something or have made an error in the computations?
    
    
    
    

       
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