Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter. It is a gas giant with an average radius of about nine and a half times that of Earth. It has only one-eighth the average density of Earth, but is over 95 times more massive.
Titan is the largest moon of Saturn, the second-largest in the Solar System and larger than any of the dwarf planets of the Solar System. It is the only moon known to have a dense atmosphere, and is the only known object in space other than Earth on which clear evidence of stable bodies of surface liquid has been found.
Rhea is the second-largest moon of Saturn and the ninth-largest moon in the Solar System, with a surface area that is compareable to the area of Australia. It is the smallest body in the Solar System for which precise measurements have confirmed a shape consistent with hydrostatic equilibrium. It was discovered in 1672 by Giovanni Domenico Cassini.
Helene is a moon of Saturn. It was discovered by Pierre Laques and Jean Lecacheux in 1980 from ground-based observations at Pic du Midi Observatory, and was designated S/1980 S 6. In 1988 it was officially named after Helen of Troy, who was the granddaughter of Cronus (Saturn) in Greek mythology. Helene is also designated Saturn XII (12), which it was given in 1982, and Dione B, because it is co-orbital with Dione and located in its leading Lagrangian point (L4). It is one of four known trojan moons.
Cassini–Huygens, commonly called Cassini, was a space-research mission by NASA, the European Space Agency (ESA), and the Italian Space Agency (ASI) to send a space probe to study the planet Saturn and its system, including its rings and natural satellites. The Flagship-class robotic spacecraft comprised both NASA's Cassini space probe and ESA's Huygens lander, which landed on Saturn's largest moon, Titan. Cassini was the fourth space probe to visit Saturn and the first to enter its orbit, where it stayed from 2004 to 2017. The two craft took their names from the astronomers Giovanni Cassini and Christiaan Huygens.
Tethys, or Saturn III, is a mid-sized moon of Saturn about 1,060 km (660 mi) across. It was discovered by G. D. Cassini in 1684 and is named after the titan Tethys of Greek mythology.
Dione is a moon of Saturn. It was discovered by Italian astronomer Giovanni Domenico Cassini in 1684. It is named after the Titaness Dione of Greek mythology. It is also designated Saturn IV.
Enceladus is the sixth-largest moon of Saturn. It is about 500 kilometers in diameter, about a tenth of that of Saturn's largest moon, Titan. Enceladus is mostly covered by fresh, clean ice, making it one of the most reflective bodies of the Solar System. Consequently, its surface temperature at noon only reaches −198 °C, far colder than a light-absorbing body would be. Despite its small size, Enceladus has a wide range of surface features, ranging from old, heavily cratered regions to young, tectonically deformed terrain.
This article provides a timeline of the Cassini–Huygens mission. Cassini was a collaboration between the United States' NASA, the European Space Agency ("ESA"), and the Italian Space Agency ("ASI") to send a probe to study the Saturnian system, including the planet, its rings, and its natural satellites. The Flagship-class uncrewed robotic spacecraft comprised both NASA's Cassini probe, and ESA's Huygens lander which was designed to land on Saturn's largest moon, Titan. Cassini was the fourth space probe to visit Saturn and the first to enter its orbit. The craft were named after astronomers Giovanni Cassini and Christiaan Huygens.
The moons of Saturn are numerous and diverse, ranging from tiny moonlets only tens of meters across to the enormous Titan, which is larger than the planet Mercury. There are 83 moons with confirmed orbits as of 2023. This number does not include the many thousands of moonlets embedded within its dense rings, nor hundreds of possible kilometer-sized distant moons that were only briefly captured by telescopes. Seven Saturnian moons are large enough to have collapsed into a relaxed, ellipsoidal shape, though only one or two of those, Titan and possibly Rhea, are currently in hydrostatic equilibrium. Particularly notable among Saturn's moons are Titan, the second-largest moon in the Solar System, with a nitrogen-rich Earth-like atmosphere and a landscape featuring dry river networks and hydrocarbon lakes, Enceladus, which emits jets of ice from its south-polar region and is covered in a deep layer of snow, and Iapetus, with its contrasting black and white hemispheres.
Dunyazad is a large crater on Saturn's moon Enceladus first discovered by the Voyager 2 spacecraft. It is named after Dunyazad, the sister of Scheherazade in The Book of One Thousand and One Nights.
Shahrazad is a large crater on Saturn's moon Enceladus first discovered by the Voyager 2 spacecraft. It is located at 47.3° North Latitude, 199.7° West Longitude and is approximately 20 kilometers across. Shahrazad is the middle crater of a prominent crater triplet on Enceladus' anti-Saturnian hemisphere. Voyager images revealed very little about this crater, however, higher resolution views of Shahrazad taken by the Cassini Spacecraft during a close flyby on March 9, 2005 reveal significant north–south fracturing that runs through all three craters of the triplet. Deep canyons mark the northern and eastern portions of Shahrazad's rim. Some evidence for viscous relaxation can be seen, but it is not nearly as significant as at Dunyazad to its immediate south or at Aladdin elsewhere on the satellite.
Samarkand Sulci is a region of grooved terrain on the surface of Saturn's moon Enceladus. The feature is centered at 30.5° North Latitude, 326.8° West Longitude, and is approximately 383 kilometers long. Samarkand Sulci consists of three parts. The southern and eastern extensions bound Sarandib Planitia on its western and northern sides, respectively. The northern portions extends into a region of cratered terrain.
Shahryar is a crater in the northern hemisphere of Saturn's moon Enceladus. Shahryar was first seen in Voyager 2 images, but was seen at much higher resolution by the Cassini spacecraft. It is located at 58.3° North Latitude, 227.5° West Longitude and is 24 kilometres (15 mi) across. Despite being nearly the same size as the nearby Sindbad crater, Shahryar does not exhibit a dome-like structure on its floor, suggesting it has not undergone significant viscous relaxation. In addition, there is very little evidence that it has experienced tectonic deformation, suggesting that Shahryar is a relatively young crater.
Harran Sulci is a region of grooved terrain on the surface of Saturn's moon Enceladus. The feature is centered at 26.7° North Latitude, 237.6° West Longitude and is approximately 276 kilometers long. Harran Sulci bounds Diyar Planitia to the north and east.
The tiger stripes of Enceladus consist of four sub-parallel, linear depressions in the south polar region of the Saturnian moon. First observed on May 20, 2005 by the Cassini spacecraft's Imaging Science Sub-system (ISS) camera, the features are most notable in lower resolution images by their brightness contrast from the surrounding terrain. Higher resolution observations were obtained by Cassini's various instruments during a close flyby of Enceladus on July 14, 2005. These observations revealed the tiger stripes to be low ridges with a central fracture. Observations from the Composite Infrared Spectrometer (CIRS) instrument showed the tiger stripes to have elevated surface temperatures, indicative of present-day cryovolcanism on Enceladus centered on the tiger stripes.
Al-Kuz is an impact crater on the anti-Saturn hemisphere of Saturn's moon Enceladus. Al-Kuz was first observed in Cassini images during that mission's March 2005 flyby of Enceladus. It is located at 18.7° South Latitude, 178.2° West Longitude, and is 9.3 kilometers across. Since the crater's formation, numerous southwest–northeast trending fractures cut across the crater, forming canyons several hundred meters deep along the crater's rim. In addition, a smaller impact occurred along the northern crater wall, forming a crater 4 kilometers wide.
Zumurrud is a large impact crater on the anti-Saturn hemisphere of Saturn's moon Enceladus. Zumurrud was first observed in Cassini images during that mission's March 2005 flyby of Enceladus. It is located at 21.9° South Latitude, 181.6° West Longitude, and is 21 kilometers across. Images taken by Cassini during its March and July 2005 flybys of Enceladus revealed a great deal about the geology of this impact crater. Since formation, Zumurrud has been modified by viscous relaxation, tectonic fracturing along the crater's rim, forming canyons hundreds of meters deep, and subsequent cratering, like the small crater along Zumurrud's western rim. In addition, brightness variations can be seen along the eastern crater wall, suggesting variations in water ice grain size.
Al-Mustazi is an impact crater located on the anti-Saturn hemisphere of Saturn's moon Enceladus. Al-Mustazi was first observed in Cassini images during that mission's March 2005 flyby of Enceladus. It is located at 20.9° South Latitude, 202.0° West Longitude, and is 10.3 kilometers across. Cassini observed numerous southwest–northeast trending fractures cutting across the southwest rim of Al-Mustazi, forming canyons several hundred meters deep. These fractures were deflected by the weakened regolith produced by the Al-Mustazi impact. This deflection produced the pattern of radiating fractures seen along the northeastern rim of Al-Mustazi.
The exploration of Saturn has been solely performed by crewless probes. Three missions were flybys, which formed an extended foundation of knowledge about the system. The Cassini–Huygens spacecraft, launched in 1997, was in orbit from 2004 to 2017.
