Fact Sheet
Green(ish) Giant
Uranus, the third-largest planet in the solar system, is putting its best showing of the year over the next few nights. It's brightest for the year, and it rises at sunset and sets at sunrise. Even so, you need binoculars to see it, near the center of Capricornus. It looks like a tiny blue-green star. The Voyager 2 spacecraft snapped this close-up image in January 1986. Uranus appears as an almost featureless greenish ball. Methane in its upper atmosphere absorbs redder wavelengths of light, so the planet reflects only the bluer wavelengths back into space.
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