WITH ITS MOON SYSTEM, RINGS OF DUST AND ICE AND OCCASIONALLY TEMPESTUOUS ATMOSPHERE, THERE’S MORE TO THIS GAS GIANT THAN MEETS THE EYE
Saturn is our Solar System’s ringed wonder –a spectacular world encircled by planes of icy debris, giving it a unique appearance. But there’s a lot more to Saturn than just its rings; this enormous world is worth exploring both for its own complexity and the fascinating family of satellites that orbit it. As the most distant Solar System object easily seen with the naked eye, Saturn orbits at an average of 1.43 billion kilometres (887 million miles) from the Sun. Its slow orbit means that Saturn takes 29.5 years to make a full circuit through the constellations of the zodiac; it was this stately movement that led ancient stargazers to associate it with the father of Jupiter in Roman mythology.
Its distance makes it a challenging object for study, even in the era of giant telescopes. Most of what we know about the planet comes from the Voyager probe flybys in the 1980s and the Cassini mission that orbited between 2004 and 2017. Earth observations, coupled with close-up images from these explorers, have revealed that what often appears to be a placid orb of creamy cloud is in fact a surprisingly active world.
SATURN’S MOONS
DAPHNIS
Dimensions: 8.6 by 8.2 by 6.4 kilometres (5.3 by 5.1 by 4.0 miles)
Mass: 0.08 x 10 12 tonnes
Orbital period: 0.59 days
Discovered: Cassini, 2005
MIMAS
Diameter: 396 kilometres (246 miles)
Mass: 37.4 x 10 15 tonnes
Orbital period: 0.94 days
Discovered: William Herschel, 1789
ENCELADUS
Diameter: 504 kilometres (313 miles)
Mass: 108.0 x 10 15 tonnes
Orbital period: 1.37 days
Discovered: William Herschel, 1789
TETHYS
Diameter: 1,062 kilometres (659 miles)
Mass: 617.4 x 10 15 tonnes
Orbital period: 1.89 days
Discovered: Giovanni Domenico Cassini, 1684
DIONE
Diameter: 1,123 kilometres (698 miles)
Mass: 1095.4 x 10 15 tonnes
Orbital period: 2.74 days
Discovered: Giovanni Domenico Cassini, 1684
RHEA
Diameter: 1,528 kilometres (949 miles)
Mass: 2306.5 x 10 15 tonnes
Orbital period: 4.52 days
Discovered: Giovanni Domenico Cassini, 1672
TITAN
Diameter: 5,149 kilometres (3,199 miles)
Mass: 134,520.0 x 10 15 tonnes
Orbital period: 15.95 days
Discovered: Christiaan Huygens, 1655
HYPERION
Dimensions: 360 by 266 by 205 kilometres (223 by 165 by 127 miles)
Mass: 5.6 x 10 15 tonnes
Orbital period: 21.28 days
Discovered: William Cranch Bond, William Lassell, 1848
IAPETUS
Diameter: 1,469 kilometres (913 miles)
Mass: 1805.6 x 10 15 tonnes
Orbital period: 79.32 days
Discovered: Giovanni Domenico Cassini, 1671
PHOEBE
Dimensions: 219 by 217 by 204 kilometres (136 by 134 by 127 miles)
Mass: 8.3 x 10 15 tonnes
Orbital period: 550 days
Discovered: William Henry Pickering, 1899