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    Re: Latitude and Longitude by "Noon Sun"
    From: Henry Halboth
    Date: 2005 Jun 6, 10:07 -0400

    It has for many years been a simple discipline of celestial navigation
    to observe bodies abeam to check on course being made good and dead ahead
    to check on speed over the ground - assuming chronometer accurate and a
    second body on appropriate azimuth not available.
    On Mon, 6 Jun 2005 12:54:16 +0000 Yourname Here 
    > Lu,
    > I applaud your reasoning. There is a lot to be learned from your
    > simple statements. It smacks of being an experienced offshore
    > Naviguesser. I think you were describing that selecting bodies abeam
    > is that the resultant LOP gives you a good basis for determening set
    > and drift.
    > Joel Jacobs
    > --
    > Visit our website
    > http://www.landandseacollection.com
    > -------------- Original message from Lu Abel :
    > --------------
    > > Charles Seitz wrote:
    > >
    > > > May I suggest a noon sight fix might suffice for verification
    > > > of the dead reckoning position required for a direction/intercept
    > > > fix? Might that fix actually be superior to a DR position that
    > > > hasn't been updated during a period of prolonged cloud cover?
    > >
    > > If I were running an "aged" DR, I think an LOP perpendicular to
    > the DR
    > > track would be the most useful way of getting a better estimated
    > > position. So a noon sight would be most useful on a north-south
    > course.
    > > If I were running more E-W, I'd personally prefer a LOP sight from
    > a
    > > body (sun? moon?) directly ahead or astern. In fact, this latter
    > can
    > > be generalized to any direction -- the best EP will likely be
    > given by
    > > an LOP perpendicular to the course and therefore from a body ahead
    > or
    > > astern.
    > >
    > > Before the really smart people on this list jump on me -- I'll
    > amend the
    > > opening statement to wishing for an LOP perpendicular to my
    > expected
    > > direction of motion (ie, if I thought I might be being set by a
    > current
    > > I'd wish for an LOP that was perpendicular to the expected COG).
    > Even
    > > more important, I might wish for a sight that gave me a LOP
    > between me
    > > and a dangerous area (shoals, coral atoll, ...) so I'd know how
    > close to
    > > it I was.
    > >
    > > Lu Abel

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