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    Re: Longitude by Sunset
    From: Gary LaPook
    Date: 2012 May 6, 19:53 -0700
    I don't recall this being discussed in the past on Navlist but we have discussed the similar method of getting a star fix and then adjusting the assumed time to make a moon line pass through the star fix. This method will provide a longitude and GMT (which is better than nothing and may be good enough) but the objection was that the precision of the derived GMT/ longitude suffers due to observational errors and also due to the slow change in the position of the Moon. This method would suffer from some of these same problems and would lack the accuracy of the traditional Lunar but also may be "good enough."

    gl


    --- On Sun, 5/6/12, Alexandre E Eremenko <eremenko@math.purdue.edu> wrote:

    From: Alexandre E Eremenko <eremenko@math.purdue.edu>
    Subject: [NavList] Re: Longitude by Sunset
    To: NavList@fer3.com
    Date: Sunday, May 6, 2012, 6:07 PM


    I tried "moonset over sea" and "...over ocean"
    on Google, and found one good movie from a space station,
    and two photos which seem completely unrealistic,
    and I suppose they are taylored.
    APOD also does not give any reasonable picture.

    Is it indeed true that one cannot see it???

    Alex.

    On Sun, 6 May 2012, Greg Rudzinski wrote:

    >
    > Gary,
    >
    > The 14th of May looks good as well. I'll give it a go.
    >
    > Greg Rudzinski
    >
    > [NavList] Re: Longitude by Sunset
    > From: Gary LaPook
    > Date: 6 May 2012 13:00
    > Wait til May 15th when the Moon will set north of straight west so you will have a clear horizon north of the islands.
    >
    > gl
    >
    > --- On Sun, 5/6/12, Greg Rudzinski &lt;gregrudzinski---com> wrote:
    >
    > From: Greg Rudzinski &lt;gregrudzinski---com>
    > Subject: [NavList] Re: Longitude by Sunset
    > To: NavList---org
    > Date: Sunday, May 6, 2012, 12:27 PM
    >
    > Alex,
    >
    > Would it be possible to compare an observation of the Moon at 2 * then follow with an observation of the Sun at 2* from the same location and height of eye to perform the time lunar you are suggesting ? Unfortunately I can't perform this experiment for a true sunset/moonset from my location because there are islands in the way :(
    >
    > Greg Rudzinski
    >
    > [NavList] Re: Longitude by Sunset
    > From: Alexandre Eremenko
    > Date: 6 May 2012 12:45
    > Marcel,
    >
    >> These few observations were at night. The (full) moon just gradually faded
    >> out when approaching the horizon.
    >
    > Perhaps there were clouds?
    > I am trying to recollect, but cannot remember any instance
    > that I've seen a moonset over the sea:-(
    >
    >> I'm still
    >> interested to know better under which conditions a moon set
    >
    > Me too.
    >
    > Alex
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