Excerpts from Jim Conrad's
Naturalist Newsletter

New Moon crescent as seen from the tropics

from the March 4, 2012 Newsletter issued from Hacienda Chichen Resort beside Chichén Itzá Ruins, central Yucatán, MÉXICO

The other night I was walking with my Estonian lady-friend Malle as a slender crescent of the Moon set in the west. Suddenly Malle stopped, looked hard at the Moon, and said it didn't look right. New Moons like this one ought to hang crookedly in the sky, she said. Their crescents should tip to one side like a bowl pouring out its water. But this Moon was hardly tipped at all. It was like a big smiley-face grin, its mouth corners about equally high. You can see that very Moon above

Of course my picture doesn't prove much, since I could have held the camera at any angle, placing the Moon in the picture in any position. I can only say that I tried to hold the camera horizontally.

When I started thinking about the issue, it also seemed to me that the new Moons of my childhood back in Kentucky were angled, not smiley like this one.

Finally I got it worked out.

The waxing Moon in the picture is setting in the west. Facing it, north is on our right. If we were to start side-stepping to our right, heading northward, eventually the Earth's curvature would cause our bodies to tilt northward, causing the Moon in the sky to seem to tilt the way Malle remembered it. Malle is from Estonia, which lies very far to the North, so the new Moons she remembers would be much more tilted than my Kentucky Moons. If that night Malle and I had been standing at the North Pole, I guess the Moon would have been tilted completely onto one side, standing on one of its cusps!