Cracked Features on Enceladus Are Very Young

[Fraser]

SUMMARY: NASA's Cassini spacecraft has discovered that the long cracks discovered on the surface of Saturn's moon Enceladus are actually quite young, between 10 and 1,000 years old. These findings support a previous discovery that Enceladus has a very active geology, and its surface features have been changing quite recently. These cracks act like vents, allowing ice and vapour to spew out. The fact that Enceladus is so active came as a surprise to scientists, as it's hard for an object this small to hold onto its heat.

View full article (http://www.universetoday.com/am/publish/cassini_finds_young_tiger_stripes.html)
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[NanC]

Hello. I read the article and the one on page 16 of November Sky & Telescope magazine for 2005. I wonder if you know why the heat could not be remaining from a large impact in the Tiger Stripes area. I look at the picture in Sky & Telescope and think it looks like an asteroid hit it and the ice flowed over the crater re-freezing after the impact melted it. The radian cracks away from the impact point make me think at first the same.

A way to tell would be if it cools off over time but I do not know how fast it would cool off. I do not know how old the hit would have to be for it to still be warm. I don't think this is sure. I am just asking if this could be true. If it was geological heat it would not cool off over time. Am I right about that?

An asteroid impact would also put material in Saturn's ring system like they observed.