Saturn's Moons as seen by Cassini

[Rick]

Enceladus Jets: Surprises in Starlight

During a recent stargazing session, NASA's Cassini spacecraft watched a bright star pass behind the plume of gas and dust that spews from Saturn's icy moon Enceladus. At first, the data from that observation had scientists scratching their heads. What they saw didn't fit their predictions.

The observation has led to a surprising new clue about the remarkable geologic activity on Enceladus: It appears that at least some of the narrow jets that erupt from the moon's surface blast with increased fury when the moon is farther from Saturn in its orbit.

Exactly how or why that's happening is far from clear, but the observation gives theorists new possibilities to ponder about the twists and turns in the "plumbing" under the moon's frozen surface. Scientists are eager for such clues because, beneath its frozen shell of ice, Enceladus is an ocean world that might have the ingredients for life.

More: http://www.jpl.nasa.gov/news/news.php?feature=6507

[Rick]

Cassini Reveals Strange Shape of Saturn's Moon Pan

These images are the closest images ever taken of Pan and will help to characterize its shape and geology.

More: https://www.jpl.nasa.gov/news/news.php?feature=6770

Also, see APOD: https://apod.nasa.gov/apod/ap170313.html

[Rick]

Cassini Sees Heat Below the Icy Surface of Enceladus

A new study in the journal Nature Astronomy reports that the south polar region of Saturn's icy moon Enceladus is warmer than expected just a few feet below its icy surface. This suggests that Enceladus' ocean of liquid water might be only a couple of miles beneath this region -- closer to the surface than previously thought.

The excess heat is especially pronounced over three fractures that are not unlike the "tiger stripes" -- prominent, actively venting fractures that slice across the pole -- except that they don't appear to be active at the moment. Seemingly dormant fractures lying above the moon's warm, underground sea point to the dynamic character of Enceladus' geology, suggesting the moon might have experienced several episodes of activity, in different places on its surface.

More: https://www.jpl.nasa.gov/news/news.php?feature=6775

[Rick]

NASA Missions Provide New Insights into 'Ocean Worlds' in Our Solar System

Two veteran NASA missions are providing new details about icy, ocean-bearing moons of Jupiter and Saturn, further heightening the scientific interest of these and other "ocean worlds" in our solar system and beyond. The findings are presented in papers published Thursday by researchers with NASA's Cassini mission to Saturn and Hubble Space Telescope.

In the papers, Cassini scientists announce that a form of chemical energy that life can feed on appears to exist on Saturn's moon Enceladus, and Hubble researchers report additional evidence of plumes erupting from Jupiter's moon Europa.

"This is the closest we've come, so far, to identifying a place with some of the ingredients needed for a habitable environment," said Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate at Headquarters in Washington. "These results demonstrate the interconnected nature of NASA's science missions that are getting us closer to answering whether we are indeed alone or not."

More: https://www.jpl.nasa.gov/news/news.php?feature=6812

[Rick]

Cassini Sees 'Flying-Saucer' Moon Atlas Up Close

These images are the closest ever taken of Atlas and will help to characterize its shape and geology. Atlas (19 miles, or 30 kilometers across) orbits Saturn just outside the A ring -- the outermost of the planet's bright, main rings.

Go and have a look: https://www.jpl.nasa.gov/news/news.php?feature=6813