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    Re: Do We Still Need to Use Sextants?
    From: Brad Morris
    Date: 2013 Apr 8, 14:35 -0400

    Hi Alan

    If your objective is to determine your position to within a degree or so of latitude and longitude, then the pendulous weight and a protractor will do, but only when conditions are calm.   This instrument is known as a quadrant, searches for this term will provide a wealth of information.

    If you wish to avoid the sextant, then a cross staff or back staff (Davis Quadrant) may suffice for better accuracy.  The cross staff will end up blinding you, due to staring directly into the sun.  The back staff is better but expect ~1/4 degree of error even after lots of practice.

    For serious angular measurement of altitude, the instrument of choice has been and will be the sextant, particularly for hand held operations.  Its simple and effective.  Error on the order of 1 to 2 minutes of arc can be achieved.

    More exotic devices can be had, but as the discussion has illustrated, the determination of vertical then becomes critical.

    Brad

    On Apr 8, 2013 2:05 PM, "Alan S" <alan202---.net> wrote:

    Jeremy:

    The possibility you suggest is perhaps a real one. That having been said, North Korea's so acting might be construed as an act of war, with suitable consequences to North Korea, these consequences originating from several sources/nations. It would be better to avoid such situations, but then are the North Koreans rational. I don't know.

    Otherwise, absent sextants, the following is perhaps a possible alternative. Using a protractor, a piece of string and a weight, the angle or attitude of a celestial body can be determined, though whether such a "shot" would be of sufficient accuracy is debatable, beyond my knowledge to determine. It might be, but quite possibly not, even assuming the availability of accurate time, and such tables as one desired to use.For those not devoted to electronic navigation, I expect that the sextant, being reasonably idiot proof, will continue to serve.
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