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    Re: Latitude and longitude around noon
    From: Francis Upchurch
    Date: 2017 Mar 3, 17:27 -0000

    I tried 3 methods.
    1) Quick and dirty. Assume noon alt 41deg30',Ho 41*36'36'', ZD 48*23', Lat 41*26.4'.
    EoT=+12'5''.LAN Greenwich=12.12.5. = 4.48.35 time difference.=72* 8.7' W
    2) Slow and dirty. Graph. LAN 16 59 16 gives Long 72*2' W
    3)equal altitudes gave same result as 2).
    Did not know to correct for the 1knot northing of the sun. Please explain Frank.
    Best wishes
    -----Original Message-----
    From: NavList@fer3.com [mailto:NavList@fer3.com] On Behalf Of Frank Reed
    Sent: 02 March 2017 21:34
    To: francis@pharmout.co.uk
    Subject: [NavList] Latitude and longitude around noon
    Four hours ago I took a series of Sun sights around local noon. Here's the raw data:
    16:35:30, 41° 13.0'
    16:40:55, 41° 20.9'
    16:48:02, 41° 25.8'
    16:55:39, 41° 28.8'
    17:00:38, 41° 30.0'
    17:02:46, 41° 28.7'
    17:06:22, 41° 27.3'
    17:12:25, 41° 23.3'
    17:19:18, 41° 15.2'
    17:23:19, 41° 09.0'
    Times are UT. Altitudes are Sun LL, as usual. Height of eye 24 feet. Index 
    error was about 3.8' on arc. Can you determine my latitude and longitude from 
    these sights? How many different ways can you come up with to get a fix from 
    these observations? Incidentally, my "northing" speed was zero, but the Sun 
    is northbound at about 1 knot this time of year.
    I was able to shoot the Moon and Venus, too, so there were ample opportunities 
    to get a celestial fix today. The weather was chilly and blustery. Great 
    waves! See photos.
    Frank Reed
    [plain text auto-generated]
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    Attached File: http://fer3.com/arc/imgx/wind-and-waves1.jpg
    Attached File: http://fer3.com/arc/imgx/wind-and-waves2.jpg
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