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Cloudy Skies

December 27, 2015

Clouds are a common sight across much of the country at this time of year. They bring snow and chilling rains, and form beautiful patterns as they drift by.

Clouds are common on the other planets of the solar system as well. Only Mercury, the planet closest to the Sun, is left out. And you can see several of these cloudy worlds at first light tomorrow.

The most prominent is Venus, the “morning star,” low in the southeast. Thanks to its clouds, you just can’t miss it. The clouds cover the entire planet, and reflect most of the sunlight that strikes them. They’re many miles thick, and they’re made mainly of sulfuric acid.

The clouds on Mars are made of something a little more familiar: water. But they’re mere wisps compared to the clouds on the other planets. Snow sometimes falls from the clouds, creating a fresh white blanket atop the orange landscape.

Mars is well to the upper right of Venus, beside the star Spica. One more cloudy world is about the same distance to Mars’s upper right: Jupiter, the giant of the solar system.

Jupiter is so big and spins so fast that most of its clouds are stretched into bands that encircle the globe. But some clouds form oval-shaped storms. The most prominent is the Great Red Spot, which has winds of a thousand miles per hour at its rim. But it’s not as great as it used to be. It’s been shrinking for several years — depriving Jupiter of some of the most interesting clouds in the solar system.


Script by Damond Benningfield, Copyright 2015

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