Milky Way Photo from Down East Maine

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Many people haven't been shown that the visible planets, Sun and Moon stay in a very narrow band running between the Eastern and Western horizons. Knowing this makes it much easier to find them. This is a consequence of (most of) the planets orbiting the Sun in a plane, and the Moon orbiting the Earth in this same plane. This path is called the ecliptic.

If you go outside and face the equator you will see the Moon and any visible planets lined up along the ecliptic. If you go outside at the same time for a number of nights, you will see the Moon farther to the east along this line every night.

The earliest crescent moon becomes visible immediately after sunset in the West. Each night it will be seen farther and farther East, and each night it will wax in size, until full, at local midnight. After that the moon wanes as it moves farther and farther East.

I don't know how to explain it, but on nights when I see the waning moon far in the East after midnight, I think of times long, long, long, long ago, before we had civilization. I've found other people share this experience.

I was lucky to go to the University of California at Irvine in the 1970s, and have a physics professor, Robert Bork, who was interested in using computers for teaching. He wrote a teaching program called Luna which explained the movement of the Moon and the Earth, and how to predict both solar and lunar eclipses. That was the best computer learning module I have ever experienced. It was written in APL, and the uncompiled source code was right there to read. That also helped with computer science classes!

If you want to learn more about predicting eclipses, find a very old book called On Stonehenge by the astronomer Fred Hoyle. He shows how that monument could have been used to predict eclipses many years into the future. I have read reviews of his book by anthropologists trying to attack his thesis that it was used as an eclipse predictor, but their attacks do not convince me.

Hoyle's book Astronomy: A History of Man's Investigation of the Universe is also the best introduction to the topic I have read, although it is now dated. If you read the book you will learn how to tell exactly where you are on the globe.