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    Re: International Date Line and Earhart/Noonan
    From: David Pike
    Date: 2022 Jan 24, 16:18 -0800

    Tony Oz you wrote:  While editing the wikipedia (Russian) article on Mr Noonan, I discovered this fine example of speculations by some "filmmaker".

    I find such speculatiuons HIGHLY insulting for any navigator, Mr Noonan especially.

    I’ll have to work this out closely tomorrow, but I don’t believe being one day out in the date would make 1 degree of longitude difference to a sun shot approximately on the nose.  True, RA Sun increases by 4 minutes of time per day, but that means SHA Sun decreases by 4 minutes of time or one degree arc per day.  However, GHA Aries increases by approximately 1 degree arc per day so GHA Sun = GHA Aries + SHA Sun is only going to decrease by the order of few minutes arc per day for a particular time of day.  The AA give about 2.7’arc.  However, it’s possible Noonan might have been using a Weems sidereal time watch, and that’s not an area of celestial I’ve studied. Incidentally, Air Navigators know they can and do makes mistakes.  That’s why they double check everything and run as many independent checks as possible simultaneously.  DaveP

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