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    Re: the answer...?
    From: Joe Shields
    Date: 1998 Sep 29, 07:59 EDT

    I agree, "around noon" the sun's altitude is changing relatively very
    little, so you can get a good latitude fix even if the timing of your
    observation is off a bit, but all attempts on my part to determine
    longitude by pin pointing the exact time of meridian passage has been
    a lot of work and squinting for dubious results.  Better to catch the
    sun near rising or setting for a good longitude fix.  Of course my
    experience is just with a cheap Davis sextant using an artificial
    horizon.
    Ocean navigator wannabee -- Joe Shields
    ---Russell Sher <rsher{at}XXX.XXX> wrote:
    >
    > You can keep the armour off for my answer Joe, perhaps just move up
    to give
    > me a place to duck behing your shield !....
    >
    > I can identify with your comment - perhaps our more experienced
    navigators
    > would not agree, but yes, I have found that it is often subjective -
    even
    > standing in the garden trying to shoot a LAN sight onto the garden
    wall
    > (just for "finding highest-altitude" practice) can be difficult and
    this was
    > in an ideal environment.
    >
    > regards
    > Russell
    >
    > > -----Original Message-----
    > > From:	Jim Manzari [SMTP:manzari{at}XXX.XXX]
    > > Sent:	Monday, September 28, 1998 8:13 PM
    > > To:	navigation{at}XXX.XXX
    > > Cc:	Russell Sher
    > > Subject:	Re: [Nml] the answer...?
    > >
    > 	Jim wrote...
    >
    > > ...I consider myself to be a reasonably experienced (celestial)
    > > navigator, but I am puzzled by the problem.  The only explanation
    that
    > > I can think of, is that you were on a heading directly opposite to
    the
    > > sun (I confess that I am not familiar with the geography of the area
    > > between Mauretania and the Schedlt) and thus the sun appeared to be
    > > decreasing in height but still approaching your meridian.
    > >
    > > And now, I have to add a bit of my own opinion regarding the noon
    sun
    > > shot.    Before I commence, put on your armour,   get your daggers
    > > ready for I am about to utter a bit of heresy.
    > >
    > > The noon sun shot is overrated.    It's beauty lies in the
    simplicity
    > > of the calculations required to obtain one's latitude, but that is
    > > where it ends.    One can easily take a few quick observations at
    > > "around" noon hour, reduce the sight as normal and plot the
    resultant
    > > east-west LOP on your chart to obtain your latitude.    This
    method is
    > > particularly useful at high latitudes where the trajectory of the
    sun's
    > > passage tends to be fairly flat and determining the exact moment at
    > > which the sun reaches its maximum height can be somewhat subjective.
    > >  In the winter time here in Iqaluit, I have sat outside, freezing my
    > > tail off, for up to 45 minutes, waiting for the sun to reach its
    > > maximum height of 3 degrees above the horizon.
    > >
    > > Even in the mid-latitudes, I have seen people up on deck taking
    > > observation after observation, trying to determine the exact
    moment of
    > > meridian passage, and even after all of that, there is no
    guarantee of
    > > a satisfactory result; I have rarely seen two people obtain the same
    > > numbers.    I am not suggesting  that the noon sun shot should be
    > > discarded - I still like to perform the operation - but it is not
    the
    > > be all and end all.
    > >
    > > Ok, allow me to put on my bullet-proof suit....fire away folks!
    > >
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