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    Re: Crescent Moon over 42nd Street NYC
    From: Matus Tejiscak
    Date: 2022 Apr 9, 15:37 -0700

    That's an interesting one, thanks Frank! I call bluff for the following reasons:

    1. The Moon is waning. That means it's morning, the Moon is rising, and we're looking East-ish.

    2. The most East-ish azimuth that I could find along the 42nd Street is about 43°. (That's its northernmost segment.)

    3. From the law of cosines, at moonrise, sin Dec = cos Zn cos Lat. That means the declination of the Moon should be above 33°N. (The true declination will be higher because Zn at moonrise was even lower than the Zn we're observing now that the Moon is higher up.)

    4. But the Moon's declination never exceeds 29°. That's a contradiction already.

    5. There's more, though: the angle of the illumination of the Moon suggests that the Sun is even further North!

    Also, from OpenStreetMap, the distance between buildings across the 42nd is 25-30 m; let's go with 25 m. For this distance to subtend roughly the angular diameter of the Moon, the picture must have been taken with a telephoto lens from about a 2.8 km distance. However, the longest straight segment of the 42nd is only 2 km long, and the northernmost segment mentioned above is only 1.5 km long. Moreover, the perspective in the photo does not look like a telephoto perspective, although I've just eyeballed that with no calculations. In other words, the Moon could not appear this big in a picture of the 42nd Street.

    That was a quick look. I wonder what the others will come up with.

       
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