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    Re: Latitude and Longitude by "Noon Sun"
    From: Robert Eno
    Date: 2005 Jun 7, 12:57 -0400

    In response to Frank's note:
    > The advantage of this Lat/Lon by Noon Sun  business is that it's very easy
    > to
    > teach, learn, and re-learn, and requires an  absolute minimum of equipment
    > and books. A navigation student who has been away  from practice in
    > navigation
    > for ten years may not remember how those tables work  anymore, but you can
    > pick
    > up Lat/Lon by Noon Sun in a few hours and have a  decent celestial fix at
    > the
    > very next noon.
    No arguement from me on this Frank. I quite enjoy the noon sun shot for its
    instant gratification. And I am not questioning its utility.
    > Tell me  then, if it is so easy, why doesn't everybody do it?? I'm not
    > kidding. I have  observed many students learning celestial and they tend
    > to come
    > from  wide-ranging educational backgrounds and skill sets. For many
    > people, it's
    > all  just damn confusing. I helped out a couple of years with a class in
    > which
    > one of  the students was a skilled, highly-paid surgeon. And he couldn't
    > make
    > heads or  tails of celestial navigation. His wife, however, loved it and
    > understood  everything.
    I have experienced the same thing. I "trained" (if you want to call it that)
    two north pole expeditioners on a simple method for maintaining a heading
    using the sun as a guide at various times of the day. I printed off a little
    table -- based on data from
    the Nautical Almanac -- for them to use so it would be easy. In this case,
    it was the reverse: the husband grasped the concepts immediately, while his
    wife simply couldn't connect. The mathematics behind celestial is not
    something that everyone can easily grasp. Why this is, I don't know because
    always been of the mind that if I can understand it, anyone can. I am not
    particularly brilliant in the field of mathematics. But then again,
    motivation has always been a strong factor for me to learn new things.
    > Where is this world where one crosses oceans without GPS? Are you
    > concerned
    > that yours might break down? The best backup for GPS is another GPS.
    I have to disagree with you on that point Frank. The ocean is a hostile
    environment and in a hostile environment, the first thing to
    if things go wrong, is usually the electronics. I am reminded of the preface
    to the second edition of the Sextant Handbook in which Bruce Bauer writes:
    "...Off the Atlantic coast recently our radar, loran, and single sideband
    radio all were smoked in one brilliant instant by a lightening stroke merely
    near our vessel -- not even a hit."
    But getting away from the hostile environment arguement, GPS is a single
    system and no matter how many receivers you have, if something goes wrong
    with the main system, you're hooped. In today's unsettled and violent world
    who is to say that DoD may not either shut the system down without warning
    or simply degrade the signals to the extent that they would be no more
    accurate than what you can obtain with a sextant?
    > Celestial navigation is no longer a primary method of navigation.
    Sadly, this is true.
    > are  plenty of
    > people who want to do it for fun and challenge and maybe, just maybe,  for
    > a
    > backup in case something happens to the main GPS *and* the various spare
    > GPS
    > receivers. There are others who do it for various certfications. But why
    > else?
    Backup and the satisfaction of being something other than a mindless
    push-button navigator.
    Wait, wait... I've got it! You're at war with another maritime
    > power. You
    > are engaged in a naval battle and the other vessel surrenders. You send an
    > officer aboard to take your prize into port and discover that the enemy
    > crew
    > have thrown overboard the ship's GPS receivers! How will you ever get your
    > prize
    > back to port. Sure, you can borrow one of the three spare GPS receivers
    > from
    > your own vessel, but what happens when you have captured two or three
    > other
    > enemy vessels?? That is when you will need your sextant and celestial
    > navigation! (in case you don't recognize this, it is a rewording of a
    > excuse for
    > studying 'longitude by lunars' from the late 19th century which I posted
    > to the
    > list a while back).
    Actually, why not just tow them all back ;-^)
    > And concluded:
    > "I  won't delve into the "what ifs" (what if my watch went overboard
    > etc.)."
    > If you're willing to entertain the highly unlikely possibility  that you
    > might cross an ocean without GPS, then dropping your watch overboard
    > seems like a
    > sure thing! 
    Actually, in 1986 while I was the navigator in a crew running a small boat
    up the west coast of Hudson Bay, I did, in fact, lose my watch overboard.
    Fortunately, we were close enough to the coast that a sextant was not
    required and in any case, we didn't have one.
    All the best

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