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    Jupiter-Moon Lunar from a photo
    From: Frank Reed
    Date: 2020 Dec 18, 20:13 -0800

    I saw this attractive photo on FB today. It shows Jupiter and Saturn approaching that very rare close conjunction, just three days away now, and we have the crescent Moon to determine the date and the UT, within reason. And there's a lighthouse! It's a nice case where you can do some serious navigation from a very simply iPhone photo. So where are you? And what is the date and time?

    Of course there's an internet search solution. I'll give you two hints: that lighthouse "eats boats" and the photographer has "gone viral"... But how do we solve this with nautical astronomy? There's only one relatively small region on the globe and one fairly brief period of time where, and when, this photo could have been taken based on the astronomical details. The Moon is the key. Can you make that astronomically-determined region and time consistent with the non-astronomical sleuthing?? 

    Frank Reed


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