Friday, December 02, 2005

Volcanoes of Ice


br




What you are seeing is an errupting ice volcano on Enceladus, a moon of Saturn. It is thought that the powerful eruption deposits ice particles in one of Saturn's outer rings. This image was taken by Cassini last week.

ETA I thought I should add this snip to clarify (taken from saturn.jpl.nasa.gov). As an artist, I hear something like "ice volcano" (or its uber-cool techie term "cryovolcanism") and I get inspired, excited, etc. But I don't wish to misinform (the scientist in me):

"At present, it is not clear if the plume particles emanating from the south pole arises because of water vapor escaping from warm ice that is exposed to the surface. Another possibility is that at some depth beneath the surface, the temperatures are hot enough for water to become liquid, which then, under pressure, escapes to the surface like a cold Yellowstone geyser. "

Image credit: NASA/JPL/Space Science Institute.

3 comments:

owen said...

Cool ! Very very very cool. I know I know.

Anonymous said...

If underneath the surface it might be hot then why is there ice on the surface of the moon? Is it because there is no true atmosphere to protect the surface from the freezing void of space?

sea dot said...

Yep- that's exactly right (if that's the reason for the geyser). The little sunlight that Enceladus gets doesn't get trapped by greenhouse gases the way it does here. It does very little to warm the planet up. If we had no atmosphere, we'd be pretty cold, too, even if our volcanoes were still erupting from a hot core.