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    An exotic lunar distance puzzle
    From: Frank Reed
    Date: 2011 May 2, 19:01 -0700

    Here is a photo taken from the International Space Station a few months ago:
    I am attaching a cleaned-up version that is rotated so that the horizon below the Moon is level with the frame of the image.

    The date of the image, March 6, 2011, can be assumed to be correct within one day. The puzzle is simple: where was the space station when the photo was taken (above what latitude and longitude) and how accurate do you think that position is, and what was the time and how accurate is that? The bright "star" in the photo in the far upper left (when the horizon is at the bottom) is Jupiter, but for the lunar distance aspect of this, I recommend using the stars that are very close to the Moon. These are various stars in one of the "fish" in the constellation Pisces. The image caption says that this is a gibbous moon, but actually it's a thin sliver of a crescent moon only about one day after New Moon. It looks more or less full by earthshine. If you look closely, you can also find the planet Uranus at about the same altitude above the horizon as the Moon. The limiting magnitude in the photo appears to be around 7.

    Note that the dip up there where the ISS orbits is pretty big! It's about 220 statute miles above the ground on average.
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