Posted: Thu, Sep 1, 2005, 1:47 PM ET (1747 GMT)
Images and other data obtained by NASA's Cassini spacecraft show that the icy Saturnian moon of Enceladus is far more active that planetary scientists originally thought. Cracks on the surface of Enceladus, dubbed "tiger stripes" because of their appearance, are no more than 1,000 years old and could be as young as 10 years old, scientists reported this week. The cracks were not seen by Voyager 2 when it flew past the moon in 1981. Scientists believe that icy material may spew out from the cracks, which may explain periods of brightening of the south polar region of the moon noticed by observers on Earth. How the small moon has managed to retain the interior heat required to drive such activity remains a mystery.

Related Links:

•  New Scientist article
•  BBC article
•  Reuters article
•  The Independent article
•  NASA press release