StarDate

Moon and Antares


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The human eye is amazing. It can focus on objects near and far, provide a three-dimensional look at the world, and see under both brilliant sunlight and the faint glow of the stars. It also sees all the colors of the rainbow – from red and orange to blue and violet.

Yet there’s a lot more that the eye can’t see – wavelengths that are beyond its range. That means we’re missing much of what the universe is showing us.

Consider Antares, the heart of the scorpion. The star is just a whisker away from the Moon as they climb into view this evening.

Antares is one of the brightest pinpoints in the night sky. And it shines with a distinctly orange hue. But there’s a lot more to it than that.

For one thing, Antares consists of two stars, not one. The one we see is a supergiant – many times the Sun’s mass, and hundreds of times its diameter. At visible wavelengths, it shines about 10,000 times brighter than the Sun, with a distinctly orange color.

But the star is much cooler than the Sun. Such stars produce most of their energy in the infrared – wavelengths too long for the human eye. So when you add that in, Antares is about a hundred thousand times the Sun’s brightness.

The other star of Antares is much hotter than the Sun. So most of its light is in the ultraviolet – wavelengths that are too short for the eye. So it is about three thousand times the Sun’s brightness – much more than the eye can see.

Script by Damond Benningfield

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StarDateBy Billy Henry