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Moon and Companions

August 12, 2016

Enceladus is a small moon with a big appeal. Water shoots into space from cracks in the ice around its south pole. That water is fed by an underground ocean that could be a good home for life.

Enceladus is the sixth-largest moon of the planet Saturn. It’s only about 300 miles in diameter, compared to more than two thousand miles for Earth’s moon.

Most moons of that size are little more than chunks of rock and ice, with surfaces marked by countless impact craters — dead worlds that attract little attention.

Enceladus, on the other hand, has a fairly young surface — vast sheets of bright, clean ice. That’s because the gravity of nearby Saturn tugs and twists at the little moon, warming its interior. That creates an ocean of liquid water below the icy crust — an ocean that may offer the right ingredients for life.

Some of the water from below makes its way to the surface, repaving the surface with fresh ice. And right now, it’s squirting out from cracks in the ice at the south pole. Saturn’s gravity constantly pulls at those fissures, preventing the escaping water from freezing and plugging them up — letting geysers of water and ice shoot far out into space.

Look for Saturn to the lower right of our own moon tonight, shining like a bright star. The even-brighter planet Mars is farther along the same line. And the star Antares, the heart of the scorpion, is below Saturn, completing a beautiful grouping in the evening sky.


Script by Damond Benningfield

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