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    Re: instances of the use of "horizon grazing" technique
    From: Greg Rudzinski
    Date: 2009 Oct 6, 16:01 -0700

    The technique that you are describing sounds like latitude by upper/
    lower transit of a star. Stars are hard to see near the horizon which
    means that the transit should be more than 5� above the horizon. The
    altitude can be approximated by finger widths (rule of finger) of an
    outstretched hand. My finger widths are about 1�45' so that four
    fingers gives a 7� measure of arc. Haven't tried the finger rule for
    celestial purposes but have had luck in piloting applications such as
    doubling the angle on the bow and wether another sailboat is gaining
    or retreating by measuring the vertical angle of the mast head.
    On Oct 6, 10:36�am, Apache Runner  wrote:
    > A number of emergency navigation sources talk about finding (very rough)
    > latitude by looking at the minimum altitude of horizon grazing stars. � �I'm
    > unaware of anyone that has actually used this technique, but perhaps someone
    > has used it in a real (as opposed to trial) situation. � Any anecdotes or
    > historical citations of this being used?
    > John Huth
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