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    Re: instances of the use of "horizon grazing" technique
    From: Peter Fogg
    Date: 2009 Oct 7, 11:13 +1100
    A little more on this:
    'Given the right situation, one could even put the twilight information in the Nautical Almanac to other uses. For example, in December 1983, Marvin Creamer, aboard the sailing vessel Globe Star,rounded Cape Horn, marking the halfway point in his "instrumentless" circumnavigation. This safe passage of Cape Horn was done using a technique one might call "latitude by twilight."

    Creamer used no instruments (not even a compass), but he did know that during the middle and end of December, Earth's position relative to the sun would produce a twilight between 56.5° S and 66.5° S latitude that would last all night.

    Cape Horn is located at about latitude 55.5° S. Therefore, as long as Globe Star was sailed far enough south to remain in continual twilight, and did not see complete darkness, the latitude would be below 55.5° S and Globe Star could sail safely to the easthence the "latitude by twilight" technique.'

    On Wed, Oct 7, 2009 at 11:08 AM, Peter Fogg <piterr11@gmail.com> wrote:
    "Marvin Creamer (born January 24, 1916) is an amateur American sailor noted for having sailed around the globe without the aid of navigational instruments. From 21 December 1982 until 17 May 1984, a total of 510 days at sea, Creamer and the crew of his 36' boat Globe Star circumnavigated the globe with no nautical aids, not even a compass or watch."
    I seem to remember that his tale was told in the very first issue of 'Ocean Navigator'.  There may also have been a book..?

    On Wed, Oct 7, 2009 at 10:54 AM, Lu Abel <lunav@abelhome.net> wrote:

    About a decade ago an adventurer did a single-handed circumnavigation
    with absolutely NO navigation instruments.   I remember that he timed
    his passage of Cape Horn to allow him to judge that he was at a safe
    south latitude by this "horizon grazing" technique.   Unfortunately I
    have no further recollection of the name of the boat or its skipper.

    Lu Abel

    Apache Runner wrote:
    > A number of emergency navigation sources talk about finding (very
    > rough) latitude by looking at the minimum altitude of horizon grazing
    > stars.    I'm unaware of anyone that has actually used this technique,
    > but perhaps someone has used it in a real (as opposed to trial)
    > situation.   Any anecdotes or historical citations of this being used?
    > John Huth
    > >
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