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    Re: GMT from Lunar Photo
    From: Bill Ritchie
    Date: 2022 Jan 14, 02:19 -0800

    Hello again, Antoine,

    I’m pleased to comply with your request, but I have doubts about the accuracy. The angle between the Moon’s path and the line from the 4 o’clock star, (HIP 104926 – HD202284), to the Moon’s center is about 140°, beyond the accepted alignment for lunars. In fact, that star would not have been occulted at all – a CPA of 5.1’ would have occurred near 00:38:35.

    From my copy image, the Moon diameter is 728px and the star (lower end of trail) to far limb distance is 967px. Their ratio to the augmented diameter of 2 * 16.37’ gives a far limb lunar distance of 43.49’. Astron calculates this to have occurred at 01:11:38. Changing either the diameter or distance pixel count by a single pixel changes the time by about 10 seconds, so I would guess the time using this star is +/- 40 secs!

    Kind regards,

    Bill Ritchie

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