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.
Saturn’s rings cast sharp shadows across the planet’s northern hemisphere in a view captured by NASA’s Cassini spacecraft in 2007 at a distance of about 1 million miles, using red, green and blue filters to produce a natural-colour view.
While not bursting with activity like its sister moon Enceladus, the surface of Saturn’s moon Dione is definitely not boring. Some parts of the surface are covered by linear features, called chasmata — bright icy cliffs among myriad fractures — which provide dramatic contrast to the round impact craters that typically cover moons.
NASA’s Cassini spacecraft captured this view of Saturn’s moon Enceladus that shows wrinkled plains that are remarkably youthful in appearance, being generally free of large impact craters.
