Spray It, Don’t Say It
Cassini’s done it again…images of Enceladus’ south-pole jets in all their icy glory are in from yesterday’s flyby! The one shown here, a raw image that I’ve rotated 180º (so south is “down”) shows the moon lit partly by sunlight (the sliver of white crescent along the left) and partly by “Saturnshine” (reflected sunlight off Saturn itself), with its now-famous ice geysers blowing streams of water ice particles into space from “tiger stripe” fissures crisscrossing its south pole. Enceladus’ shadow even cuts through some of the jets on the right side!
Analysis of data acquired during a flyby last August has shown that the temperatures within these fissures are higher than previously thought…where the geysers are erupting the temperature is -120º F, rather chilly by our standards but positively scorching when compared to the -240º temperatures found just outside of the fissures, and it’s even colder on the rest of the moon! The fact that these fissures are radiating such heat on a tiny, icy world so far from the Sun points to some interesting geologic processes in action, not to mention that there’s clearly liquid water involved. This is what makes Enceladus so fascinating to astronomers.
Read more about Enceladus on the Cassini imaging center’s site. And keep an eye out for more images from the November 30th flyby here!
Image: NASA / JPL / Space Science Institute.