NASA’s Cassini spacecraft has observed geysers erupting on Saturn’s icy moon Enceladus since 2005, but the process that drives and sustains these eruptions has remained a mystery. Now, scientists have pinpointed a mechanism by which cyclical tidal stresses exerted by Saturn can drive Enceladus’s long-lived eruptions.
New research suggests that some of Saturn’s icy moons, as well as its famous rings, might be modern adornments. Their dramatic birth may have taken place a mere 100 million years ago. This would date the formation of the major moons of Saturn, with the exception of more distant Titan and Iapetus, to the relatively recent Cretaceous Period — the era of the dinosaurs.
Three of Saturn’s moons — Tethys, Enceladus and Mimas — are captured in this group photo from NASA’s Cassini spacecraft. Tethys appears above the rings, while Enceladus sits just below centre and Mimas hangs below and to the left of Enceladus. This view looks toward the sunlit side of the rings from narrowly above the ring plane.
NASA’s Cassini spacecraft has begun transmitting data and images from the mission’s 22nd and final close flyby of Saturn’s active moon Enceladus on Saturday, 19 December. Cassini has made so many breathtaking discoveries about this icy moon, its geologic activity and global ocean that lies beneath its icy crust, yet so much more remains to be done to determine if this tiny ocean world could harbour life.
This view of Saturn’s moon Enceladus above the planet’s ring plane was captured by the narrow-angle camera of NASA’s Cassini spacecraft at a distance of approximately 630,000 miles (1 million kilometres) from the tiny water world. 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.
Although Saturn’s moons Dione (near) and Enceladus (far) are composed of nearly the same materials, Enceladus has a considerably higher reflectivity than Dione. As a result, it appears brighter against the dark night sky. This image was taken by NASA’s Cassini spacecraft in visible light with the narrow-angle camera on 8 September 2015.
On Wednesday, 28 October 2015, NASA’s Cassini spacecraft will take the deepest dive ever through the plume of ice, water vapour and organic molecules spraying from the south polar region of Saturn’s moon Enceladus. Scientists hope this close flyby will shed light on what’s happening beneath the moon’s icy surface. With a global ocean and likely hydrothermal activity, could Enceladus have the ingredients needed to support simple forms of life?
NASA’s Cassini spacecraft has begun returning its best-ever views of the northern extremes of Saturn’s icy, ocean-bearing moon Enceladus. Scientists expected the north polar region of Enceladus to be heavily cratered, based on low-resolution images from the Voyager mission, but the new high-resolution Cassini images show a landscape of stark contrasts.
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