StarDate

The Great Serpent


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The stars look like they’re stuck in position – like fairy lights thumbtacked to a giant black canvas overhead. And over the course of a human lifetime – or many lifetimes – that’s true – there’s no way to see any motion without the help of sensitive instruments.

But that’s only because the stars are so far away. Every one of those little lights is moving – fast. They’re all orbiting the center of the Milky Way Galaxy, for example. And they’re moving either toward or away from Earth. So over millions of years, the configuration of the stars changes – constellations come and go. And the pattern of brightness changes as well – some stars fade, others grow brighter.

An example is Eltanin, the brightest star of Draco, the dragon. In fact, its name means “the great serpent.” It represents one of the dragon’s glowing eyes.

Today, Eltanin is a bit more than 150 light-years away. But it’s moving more or less toward us at more than 60,000 miles per hour. On the scale of the galaxy, that’s tiny – but it adds up. In about one and a half million years, it’ll be just 28 light-years away. If the star doesn’t change much over that period, it could be the brightest star in Earth’s night sky. And it could maintain that rating for hundreds of thousands of years.

Look for Eltanin high in the northeast at nightfall. It’s to the upper left of Vega, one of the brighter stars in the night sky – for now.

Script by Damond Benningfield

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StarDateBy Billy Henry

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