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    Re: Longitude from Local Apparent Noon Altitudes
    From: Bruce J. Pennino
    Date: 2012 Aug 20, 08:22 -0400

    I'm always reluctant to provide what may be over precise numbers. I've seen too many disagreements over data when the preciseness of the technique does not predict truly  accurate (true )values.  That is the reason I indicated my location just east of Snail road intersecting Rt 6A (also called Bradford Street) at the bay (not Rt 6).  Rts 6 and 6A frequently cause confusion .

    I used Itouchmap.com for lat and long...primarily because it is easy and it gives visuals and maps with names.  My computer skills are only average or less.

    So, with that information..... itouch gives N42d 03m 42 sec  70d 09m 37 sec.  Just go about 400 ft east of Snail road intersection with rt 6A(Bradford). There is a large motel and parking lot on north side of Rt 6A . Small white sundeck on south side of route 6A, just at water's edge was my location.

    Have a good day.

    On Sun, Aug 19, 2012 at 11:56 PM, =?utf-8?Q?Antoine Cou=C3=ABtte?= wrote:

     Thanks for your reply, Bruce

    I am happy that we got other contributor's positions from Greg, Hewitt and Peter.
    Will you come up also, Andrés also with your own results (error ellipse) ?
    Would you mind, Bruce, if possible giving us a more accurate position about your actual location - using Google Earth for example.
    Google Earth indicates that N42°04' W070°10' is slightly North of what seems to be Rt 6, while you were apparently definitely south of Rt 6.
    You LAN observations results are quite nice. Latitude is certainly more reliably determined than Longitude here, as is always the case. Any improvement/tightening in the dispersion of the sights will definitely help finding a more accurate position. Indicating also pressure and temperature will also (marginally) help into getting a better tuned position.
    Thanks again and Best Regards
    If you look at an aerial of Provincetown ,MA,  Snail Road leaves Rt 6 and goes toward bay. Snail Road meets 6A.  I was just 300-400 ft  east  of there standing on a sun bathing deck adjacent to the water.Actually, the deck overhangs the beach/water at high tide. This location is directly north of the point you determined.
    From "eyeballing data" and  folding graph, I guesstimated UT of 16h43m56sec.
    Based on an online calculator,  the sun deck location is N 42 04'   W 070 10'. Your analysis...very well done!
    My "analysis" gave me N 42 06 W 70 00.......learning!
    Thanks all
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