This view of Saturn’s moon Enceladus narrowly above the planet’s ring plane was captured by the narrow-angle camera of NASA’s Cassini spacecraft on 29 July 2015 at a distance of approximately 630,000 miles (1.0 million kilometres) from Enceladus. Enceladus is subject to forces that heat a global ocean of liquid water under its icy surface, resulting in its famous south polar water jets which are just visible below the moon’s dark, southern limb. Image credit: NASA/JPL-Caltech/Space Science Institute.Although Enceladus and Saturn’s rings are largely made up of water ice, they show very different characteristics. The small ring particles are too tiny to retain internal heat and have no way to get warm, so they are frozen and geologically dead. Enceladus, on the other hand, is subject to forces that heat its interior to this very day. This results in its famous south polar water jets, which are just visible below the moon’s dark, southern limb, along with a sub-surface ocean.
Recent work by Cassini scientists suggests that Enceladus (313 miles or 504 kilometres across) has a global ocean of liquid water under its surface. This discovery increases scientists’ interest in Enceladus and the quest to understand the role of water in the development of life in the solar system.
This view looks toward the unilluminated side of the rings from about 0.3 degrees below the ring plane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on 29 July 2015.
The view was acquired at a distance of approximately 630,000 miles (1.0 million kilometres) from Enceladus and at a Sun-Enceladus-spacecraft, or phase angle of 155 degrees. Image scale is 4 miles (6 kilometres) per pixel.
Pan and moons like it have profound effects on Saturn’s rings. The effects can range from clearing gaps, to creating new ringlets, to raising vertical waves that rise above and below the ring plane. All of these effects, produced by gravity, are seen in this image from the Cassini probe.
Ground controllers at NASA’s Jet Propulsion Laboratory confirmed Thursday the Cassini spacecraft survived its first trip between Saturn and its rings, the closest any probe has ever come to the planet.
Laboratory experiments on Earth can now simulate the conditions under which life might emerge on Saturn’s moon Enceladus, as well as other icy alien worlds, according to new research published in journal Astrobiology.