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    Re: An exotic lunar distance puzzle
    From: David Fleming
    Date: 2011 May 4, 14:32 -0700

    Greg we essentially agree on the apparent jupiter moon lunar distance. I make it to be 12d 24m, you said 13 d. This is an apparent center to center distance which to be accurate needs to be corrected for parallax which I believe to be 1d (making the distance smaller) at an angle of about 45 from the center to center direction.

    In order to get a time for my planitarium software I ignored the parallax correction and possible lens distortion for the large field and estimated the time as GMT 02h 06m 3/6/11. I only used this to help with star identification. In reviewing the star identification I need to make a correction there and that changes my moon position and of course my answer for time.

    Corrected Star Identification

    7) Uranus lower left corner: 23h 59m 54s RA; 0d 46m 28s S Dec

    1) 7 oclock 2 moon dia.: 19 Piscium at 23h 46m 58s RA; 3d 32m 56s N Dec

    2) 11 oclock 1 moon dia.: SAO 128425 at 23h 52m 28s RA; 4d 48m 27s N Dec

    3) 2 oclock 4 moon dia.: 17 Piscium at 23h 40m 31s RA; 5d 41m 12s N Dec

    4) 3 oclock 10 moon dia.: 10 Piscium at 23h 28m 32s RA; 6d 26m 25s N Dec

    5) 12 oclock 10 moon dia.: 28 Piscium at 23h 59m 53s RA; 6d 55m 30s N Dec

    x) are labels associated with my photo.

    3) is now a different star in the picture and 4) is an additional star not previously identified.

    Corrected Moon apparent position:
    23h 48m 47s RA
    4d 24m N Dec
    RA is about same as before Dec about 40m smaller!

    Correct above for 1d of parallax (increasing Dec & RHA both by .707d as coordinates tilted to horizon by about 45 degrees) and we have:

    Moon measured position:
    5.111d N Dec
    23h 51m 37s RA

    I will finish this at a later time.

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