Saturn’s sixth-largest moon, Enceladus (504 kilometers or 313 miles across), is the subject of much scrutiny, in large part due to its spectacular active geysers and the likelihood of a subsurface ocean of liquid water. NASA’s Cassini orbiter has studied Enceladus, along with the rest of the Saturnian system, since entering orbit in 2004. Studying the composition of the ocean within is made easier by the constant eruptions of plumes from the surface, and on October 28, Cassini will be making itsdeepest-ever dive through the ocean spray from Enceladus—passing within a mere 30 miles of theicy surface. Collected here are some of the most powerful and revealing images of Enceladus made by Cassini over the past decade, with more to follow from this final close flyby as they arrive.
Ring shadows line the face of distant Saturn, providing a backdrop for the brilliant, white sphere of the icy moon Enceladus. The image was taken by the orbiting Cassini spacecraft on June 28, 2007, at a distance of approximately 291,000 kilometers (181,000 miles) from Enceladus. Image scale is approximately 2 kilometers (1 mile) per pixel.NASA / JPL / Space Science Institute
Cassini narrow-angle camera looks across the geyser basin at the south pole of Enceladus on November 30, 2010. The shadow of the body of Enceladus on the lower portions of the jets is clearly seen. The image scale is 1280 feet (390 meters) per pixel.NASA / JPL / Space Science Institute
A closeup of the surface of Enceladus on November 21, 2009, viewed from approximately 1,260 miles (2,028 kilometers) away.NASA / JPL / Space Science Institute
An animation made from 36 images taken of Saturn’s moon Enceladus on May 10, 2015 by NASA’s Cassini orbiter. The icy moon turns in the image as Cassini flies past, showing the three-dimensional structure of the constantly streaming ice plumes erupting from the surface. Most of the white spots appearing in the background are camera noise or streaks made by collisions with cosmic rays. #NASA / JPL / Space Science Institute
Enceladus’ northern latitudes imaged, with Saturn's rings peeking through in the distance, on December 21, 2010.NASA / JPL / Space Science Institute
The fractured and cratered surface of Enceladus, photographed during a close flyby on October 14, 2015.NASA / JPL / Space Science Institute
The brightly reflective moon Enceladus appears before Saturn's rings while the larger moon Titan looms in the distance on March 12, 2012.NASA / JPL / Space Science Institute
Jets of water vapor and ice erupt from the fissures in the surface of Enceladus, as seen during a flyby on October 1, 2011.NASA / JPL / Space Science Institute
An enhanced-color mosaic of Enceladus imaged on October 9, 2008. Craters and cratered terrains are rare in this view of the southern region of the moon's Saturn-facing hemisphere. Instead, the surface is replete with fractures, folds, and ridges—all hallmarks of remarkable tectonic activity for a relatively small world. In this enhanced-color view, regions that appear blue-green are thought to be coated with larger grains than those that appear white or gray. The prominent one-kilometer-deep chasm located on the right side has been named Labtayt Sulci.NASA / JPL / Space Science Institute
A pair of Saturn's moons appear insignificant compared to the immensity of the planet in this Cassini spacecraft view. Enceladus, the larger moon is visible as a small sphere, while tiny Epimetheus (70 miles, or 113 kilometers across) appears as a tiny black speck on the far left of the image, just below the thin line of the rings. The rings cast wide shadows on the southern hemisphere of the planet, imaged on November 4, 2011.NASA / JPL / Space Science Institute
The fractured and cratered surface of Enceladus photographed during a close flyby on October 14, 2015.NASA / JPL / Space Science Institute
At least four distinct plumes of water ice spew out from the south polar region of Saturn's moon Enceladus in this dramatically illuminated image taken on December 25, 2009. Light reflected off Saturn is illuminating the surface of the moon while the sun, almost directly behind Enceladus, is backlighting the plumes.NASA / JPL / Space Science Institute
Wispy fingers of bright, icy material reach tens of thousands of kilometers outward from Saturn's moon Enceladus into the E ring, while the moon's active south polar jets continue to fire away on September 15, 2006. This structure is made visible with the sun almost directly behind the Saturn system from Cassini's vantage point. The sun-Enceladus-spacecraft angle here is 175 degrees, a viewing geometry in which structures made of tiny particles brighten substantially. These features are very likely the result of particles injected into Saturn orbit by the Enceladus geysers: Those injected in the direction of the moon's orbital motion end up on larger, slower orbits and trail Enceladus in its orbit, and those injected into the opposite direction end up smaller, faster orbits and lead Enceladus. In addition to the wisps, another unexpected detail is the dark gore in the center of the ring, following the moon in its orbit, likely brought about by the sweeping action of Enceladus as it orbits in the center of the E ring.NASA / JPL / Space Science Institute
Enceladus brightly reflects sunlight before a backdrop of Saturn's rings and the rings' shadows cast onto the planet on November 30, 2010.NASA / JPL / Space Science Institute
An image taken during Cassini's very close flyby of Enceladus on August 11, 2008, showing the terrain littered with blocks of ice. The image was taken at a distance of approximately 2,446 kilometers (1,396 miles) above the surface. Image scale is approximately 18 meters (59 feet) per pixel.NASA / JPL / Space Science Institute
Small water ice particles fly from fissures in the south polar region of Saturn's moon Enceladus in this image taken during the August 13, 2010 flyby.This view looks toward the night side of Saturn, which is in the lower left of the image. Enceladus, in the top right, is closer to the spacecraft than the planet is in this view. Sunlight scatters through the planet's atmosphere and forms the bright diagonal line running from the left to bottom right of the image. The atmosphere appears layered here, and scientists think the different layers on the limb are real and not an artifact of the camera's exposure.NASA / JPL / Space Science Institute
NASA's Cassini spacecraft zoomed by Enceladus on October 14, 2015, capturing this stunning image of the moon's north pole.NASA / JPL / Space Science Institute
Enceladus reflects sunlight brightly while the planet and its rings fill the background of this Cassini view on December 21, 2010.NASA / JPL / Space Science Institute
Dramatic plumes, both large and small, spray water ice and vapor from many locations along the famed "tiger stripes" near the south pole of Saturn's moon Enceladus on February 2, 2010. The tiger stripes are four prominent, approximately 84-mile-long (135 kilometers) fractures that cross the moon's south polar terrain. This two-image mosaic is one of the highest resolution views acquired by Cassini during its imaging survey of the geyser basin capping the southern hemisphere. It clearly shows the curvilinear arrangement of geysers, erupting from the fractures. From left to right, the fractures are Alexandria, Cairo, Baghdad, and Damascus.NASA / JPL / Space Science Institute
A view of Enceladus and Saturn on October 28, 2007, from approximately 856,509 miles (1,378,418 kilometers) away.NASA / JPL / Space Science Institute
During its very close flyby of Enceladus on March 9, 2005, Cassini captured this icy landscape that has been scored by tectonic forces. Many of the craters in this terrain have been heavily modified, such as the 10-kilometer-wide (6 miles) crater near the upper right that has prominent north-south fracturing along its northeastern slope.NASA / JPL / Space Science Institute
During a flyby of Saturn's moon Enceladus on October 1, 2011, the Cassini spacecraft snapped this portrait of the moon joined by its sibling moon Epimetheus, and the planet's rings.NASA / JPL / Space Science Institute
A view across the region of Enceladus' geyser basin and down on the ends of the Baghdad and Damascus fractures that face Saturn on August 13, 2010. Image scale is about 230 feet (70 meters) per pixel.NASA / JPL / Space Science Institute
Enceladus, seen beyond the outline of the planet's night side, spews water ice from its south polar region on December 25, 2009. This unusual view of the planet and rings is possible because some sunlight scatters through the uppermost part of Saturn's atmosphere to reach Cassini's cameras on the night side of the planet.NASA / JPL / Space Science Institute
Beyond Enceladus and Saturn’s rings, Titan, Saturn’s largest moon, is ringed by sunlight passing through its atmosphere. Enceladus passes between Titan and Cassini in this image made on June 10, 2006.NASA / JPL / Space Science Institute
Close view of the surface of Enceladus on October 31, 2008, from a distance of approximately 661 miles (1,063 kilometers) away.NASA / JPL / Space Science Institute
Mosaic of of Enceladus' north polar region, made on March 14, 2008. Compared to much of the moon's southern hemisphere—the south polar region in particular—the north polar region is much older and covered with craters. These craters are captured at different stages of disruption and alteration by tectonic activity and probably past heating from below. Many of the craters seen here are sliced by small parallel cracks that seem to be ubiquitous throughout the old cratered terrains on Enceladus. The mosaic also shows a variety of impact crater shapes, some with bowed-up floors and smaller craters within, very likely indicating that the icy crust in this area was at some time warmer than at present.NASA / JPL / Space Science Institute
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