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Changing Addresses

August 15, 2015

The light of the “evening star” has been switched off. But the “morning star” will switch on in just a few days. That’s because the planet Venus is changing addresses today. It’ll cross the line between Earth and the Sun, moving from the evening sky to the morning sky. It’ll be lost in the Sun’s glare for a few days, but will climb into easy view by month’s end.

It seems obvious that the morning star and evening star are the same object. They’re the same brightness, they’re in view for the same amount of time — and like Bruce Wayne and Batman, you never see both of them at the same time.

Yet it took some cultures a while to figure that out. The Greeks, for example, thought of the morning and evening stars as two separate objects. The morning star was known as Phosphoros, while the evening star was Hesperos. The Greeks didn’t unite the two until about 2500 years ago.

One culture that wasn’t fooled by Venus’s dual identity was the Maya of Central America. Venus was the most important object in the night sky — it played key roles in everything from festivals to warfare. So the Maya carefully plotted Venus’s motions across the sky. They developed tables that allowed them to predict just where Venus would be far in the future — morning or evening.

And you can start looking for Venus in just a few days, quite low in the east just before sunrise. It’ll quickly take its place as the brilliant morning star — a spot it’ll keep until spring.

Script by Damond Benningfield, Copyright 2015

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