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The Llama

May 25, 2016

Late spring is a good time to look for the constellation Centaurus, the mythological half-man, half-horse. His head and shoulders are visible from most of the United States. They stand due south, quite low above the horizon, about three hours after sunset, and set in the wee hours of the morning.

But the constellation’s two brightest stars, Alpha and Beta Centauri, are visible only from Hawaii and far South Texas and Florida. Alpha Centauri is to the left, and is the brighter of the two.

Skywatchers in the southern hemisphere have a gorgeous view of the entire centaur as it passes high overhead. And one South American culture — the descendants of the Inca — sees some of these stars as part of a llama. Alpha and Beta Centauri represent the llama’s eyes.

Alpha Centauri actually consists of three separate stars that are bound to each other by their mutual gravitational pull. They’re the closest stars to Earth, at a distance of about four-and-a-third light-years. But they’re still so far away that their light blurs together into a single pinpoint. Only a telescope reveals the true nature of the llama’s eye.

Beta Centauri is also a triple-star system. Its two most impressive stars are locked in a close orbit. Both stars are more than 10 times as massive as the Sun, and thousands of times brighter. They make the system easily visible from Earth even though it’s almost 400 light-years away — a hundred times farther than the llama’s other bright eye.


Script by Damond Benningfield

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