Saturn's northern hemisphere, seen in 2016, as that part of the planet nears its northern hemisphere summer solstice in May of 2017. Saturn's year is nearly 30 Earth years long, and during its long time there, Cassini has observed winter and spring in the north, and summer and fall in the south. #

The wavemaker moon, Daphnis, is featured in this view, taken as NASA's Cassini spacecraft made one of its ring-grazing passes over the outer edges of Saturn's rings on Jan. 16, 2017. This is the closest view of the small moon obtained yet. Daphnis (5 miles or 8 kilometers across) orbits within the 42-kilometer (26-mile) wide Keeler Gap. Cassini's viewing angle causes the gap to appear narrower than it actually is, due to foreshortening. The little moon's gravity raises waves in the edges of the gap in both the horizontal and vertical directions. A faint, narrow tendril of ring material follows just behind Daphnis (to its left). This may have resulted from a moment when Daphnis drew a packet of material out of the ring, and now that packet is spreading itself out. #

A close-up view of Saturn's rings taken on December 18, 2016. Visible at left is a density wave in Saturn's A ring that lies around 134,500 km from Saturn. Density waves are accumulations of particles at certain distances from the planet. This feature is filled with clumpy perturbations, which researchers informally refer to as "straw." The wave itself is created by the gravity of the moons Janus and Epimetheus, which share the same orbit around Saturn. Elsewhere, the scene is dominated by "wakes" from a recent pass of the ring moon Pan. #

This image shows a region in Saturn's outer B ring. NASA's Cassini spacecraft viewed this area at a level of detail twice as high as it had ever been observed before. The view here is of the outer edge of the B ring, at left, which is perturbed by the most powerful gravitational resonance in the rings: the "2:1 resonance" with the icy moon Mimas. This means that, for every single orbit of Mimas, the ring particles at this specific distance from Saturn orbit the planet twice. This results in a regular tugging force that perturbs the particles in this location. Image made on December 18, 2016. #

Saturn's rings obscure part of Titan's colorful visage in this image from NASA's Cassini spacecraft taken on August 29, 2012. The south polar vortex that first appeared in Titan's atmosphere in 2012 is visible at the bottom of this view. The northern part of the moon's atmosphere visible here includes the north polar hood, a cap of haze looking slightly darker than the rest of the atmosphere and seen near the top of the moon. Parts of the rings appear dark near the center of this view because of the shadow cast by the planet. However, a sliver of illuminated Titan can be seen through the Cassini Division in the rings near the middle of this darkness. #

Cassini paused during its final close flyby of Enceladus to focus on the icy moon's craggy, dimly lit limb, with the planet Saturn beyond on December 19, 2015. Layers can be seen in the high hazes of Saturn's upper atmosphere, in the gradient that separates the planet from space. #

It may look as though Saturn's moon Mimas is crashing through the rings in this image taken on October 23, 2016, but Mimas is actually 28,000 miles (45,000 kilometers) away from the rings. There is a strong connection between the icy moon and Saturn's rings, though. Gravity links them together and shapes the way they both move. #

At first glance, Saturn's rings appear to be intersecting themselves in an impossible way. In actuality, this view from NASA's Cassini spacecraft shows the rings in front of the planet, upon which the shadow of the rings is cast. And because rings like the A ring and Cassini Division, which appear in the foreground, are not entirely opaque, the disk of Saturn and those ring shadows can be seen directly through the rings themselves. Saturn's little moon Pan (17 mi or 28 km across) is visible here near image center. Photo taken on February 11, 2016. #

Saturn's rings are so expansive that they often sneak into Cassini's pictures of other bodies. Here, they appear with the planet in a picture taken during a close flyby of Dione on August 17, 2015. #

Cassini peered out over the northern territory on Saturn's moon Enceladus, capturing this view of two different terrain types. A region of older terrain covered in craters that have been modified by geological processes is seen at right, while at left is a province of relatively craterless, and presumably more youthful, wrinkled terrain. Cassini acquired the view on December 19, 2015. #

Vertical structures, among the tallest seen in Saturn's main rings, rise abruptly from the edge of Saturn's B ring to cast long shadows on the ring in this image taken by NASA's Cassini spacecraft two weeks before the planet's August 2009 equinox. Cassini's narrow angle camera captured a 1,200-kilometer-long (750-mile-long) section arcing along the outer edge of the B ring. Here, vertical structures tower as high as 2.5 kilometers (1.6 miles) above the plane of the rings -- a significant deviation from the vertical thickness of the main A, B and C rings, which is generally only about 10 meters (about 30 feet). Cassini scientists believe that this is one prominent region at the outer edge of the B ring where large bodies, or moonlets, up to a kilometer or more in size, are found. It is possible that these bodies significantly affect the ring material streaming past them and force the particles upward, in a "splashing" manner. #

The water-world Enceladus appears here to sit atop Saturn's rings like a drop of dew upon a leaf. Even though it appears like a tiny drop before the might of the giant Saturn on on May 25, 2015. #

Cassini zoomed by Saturn's icy moon Enceladus on October 14, 2015, capturing this stunning image of the moon's north pole. Scientists expected the north polar region of Enceladus to be heavily cratered, based on low-resolution images from the Voyager mission, but high-resolution Cassini images show a landscape of stark contrasts. Thin cracks cross over the pole -- the northernmost extent of a global system of such fractures. #

Like a cosmic bull's-eye, Enceladus and Tethys line up almost perfectly for Cassini's cameras. Since the two moons are not only aligned, but also at relatively similar distances from Cassini, the apparent sizes in this image are a good approximation of the relative sizes of Enceladus (313 miles or 504 kilometers across) and Tethys (660 miles or 1,062 kilometers across). Image made on September 24, 2015. #

It's difficult to get a sense of scale when viewing Saturn's rings, but the Cassini Division (seen here between the bright B ring and dimmer A ring) is almost as wide as the planet Mercury. The 2,980-mile-wide (4,800-kilometer-wide) division in Saturn's rings is thought to be caused by the moon Mimas. Image made on January 28, 2016 #

Saturn's moon Tethys appears to float between two sets of rings in this view, but it's just a trick of geometry. The rings, which are seen nearly edge-on, are the dark bands above Tethys, while their curving shadows paint the planet at the bottom of the image, taken on November 23, 2015. #

Saturn's A and F rings appear bizarrely warped where they intersect the planet's limb, whose atmosphere acts here like a very big lens. In its upper regions, Saturn's atmosphere absorbs some of the light reflected by the rings as it passes through. But absorption is not the only thing that happens to that light. As it passes from space to the atmosphere and back out into space towards Cassini's cameras, its path is refracted, or bent. The result is that the ring's image appears warped. The image was taken on June 9, 2016. #