Enceladus

noun

En·​cel·​a·​dus en-ˈse-lə-dəs 

astronomy

: the sixth largest satellite of Saturn that has a diameter of approximately 310 miles (500 km) and is characterized by geological activity and the presence of liquid water

Images revealed a terrain of faults, folds, and ridges devoid of craters, further evidence that Enceladus is one of the most geologically active places in the solar system.

—Ron Cowen, Science News, 6 May 2006

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