The Moon and the “evening star” stage a beautiful encounter early tonight. They’re close together as the Sun sets. They’re an especially beautiful sight because they’re immersed in the colors of twilight.

Despite its appearance, the evening star isn’t a star at all -- it’s the planet Venus.

Long before the invention of the telescope, skywatchers knew there was something different about this brilliant light. While the true stars all maintain their position relative to each other, Venus and the other “planets” change position from week to week or even night to night. That’s why they’re called planets -- an ancient Greek word that means “wanderers.”

Those wandering lights were a nuisance to those who tried to explain the workings of the heavens. Most thought that Earth was the center of the universe. And that seemed to be a reasonable explanation for the Sun, Moon, and stars.

But it was harder to explain the motions of the planets. They periodically stop and reverse course. And Venus swings between evening and morning skies, always staying close to the Sun. In fact, it’ll move into the morning sky in less than a month. The explanations for these motions got pretty complicated, which made them hard to believe.

These complicated motions convinced astronomers that Earth circles the Sun, along with the other planets -- moving our world out of the center of the universe.

More about the Moon and another planet tomorrow.
 

Script by Damond Benningfield

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