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    A small puzzle
    From: Richard B. Emerson
    Date: 2000 Sep 06, 9:58 PM

    While sailing back from New England, coasting down the New Jersey
    coast, I did some morning sights even though I was fairly close to my
    final destination.  For one reason and another, I was only able to get
    off shots for Jupiter, the Moon, and one star.  Although the angle
    between Jupiter and the Moon was only about 35 degrees, the lines were
    generally usable and confirmed my position.  The reductions for the
    star, however, failed miserably and I have yet to figure out what went
    wrong.  I was pretty sure I was shooting Betelgeuse but when I reduce
    the sights, the distance to the GP is something awful (about 80 miles,
    to!).  Now, it was early in the morning, I'd been up much of the
    night and we'd been traveling fairly hard for about a week, so I was
    hardly the crispest cookie in the box.  [g]  My first thought was that
    I'd made a timing error.  I've been using a stopwatch and writing down
    the hack time when I start the watch.  The stopwatch is a 30 minute
    watch and it doesn't have a telltale for rolling over from one half
    hour to the next.  With all of this in mind, here's the setup:
    
    The date is 22 Aug 2000, the AP is 39-04 N 74-40 W, the course and
    speed are 224T at 5.8 kt.  He is 5' and Ic is 2.0' on.  The horizon
    was clear and the sky was clear, too.  My notes show the initial hack
    time was 09:20Z (05:20EDT) (the hack changes for the last two bodies;
    I waited for a lighter horizon).  What follows are typed versions of
    my notes; I've added the UTC times as well as watch times.  Also, it's
    helpful to know the bearing to Betelgeuse at the time was
    approximately 110T.  Finally, I chose Betelgeuse because its reddish
    color makes it distinctive in the sextant's scope (4x).
    
    Sight No.   Time (WT/UTC)    Hs
    Betelgeuse(?)
    01          08:20 09:28:20   36-23.5
    02          09:34 09:29:34   36-42.0
    03          10:34 09:30:34   36-52.5
    
    NOTE!
    New hack time: 09:49Z
    
    Jupiter
    04          02:04 09:51:04   63-10.0
    05          03:09 09:52:09   63-18.0
    06          04:04 09:53:04   63-25.5
    
    Moon (Lower Limb)
    07          05:48 09:54:48   63-53.0
    08          07:05 09:56:05   63-58.0
    09          07:56 09:56:56   63-59.5
    
    Your mission, if you choose to accept it, is to figure out what went
    wrong with the star sight.
    
    Rick
    S/V One With The Wind, Baba 35
    

       
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