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Tethys,in Greek religion and mythology, a Titan, daughter of Gaea and Uranus. She was the wife of the seagod Oceanus and the mother of the Oceanids.
Tethys(tē`thĭs), in astronomy, one of the named moons, or natural satellites, of SaturnSaturn,
in astronomy, 6th planet from the sun. Astronomical and Physical Characteristics of Saturn
Saturn's orbit lies between those of Jupiter and Uranus; its mean distance from the sun is c.886 million mi (1.
..... Click the link for more information. . Also known as Saturn III (or S3), Tethys is 659 mi (1060 km) in diameter, orbits Saturn at a mean distance of 183,093 mi (294,660 km), and has equal orbital and rotational periods of 1.8878 earth days. Tethys was discovered by the Italian-French astronomer Gian Domenico CassiniCassini
, name of a family of Italian-French astronomers, four generations of whom were directors of the Paris Observatory. Gian Domenico Cassini, 1625–1712, was born in Italy and distinguished himself while at Bologna by his studies of the sun and planets,
..... Click the link for more information. in 1684. Tethys's low density (1.2) implies that is composed primarily of water ice. The heavily cratered satellite has two dominant surface features: one is an impact crater—called Odysseus—about 250 mi (400 km) in diameter that is quite flat and without the high wall and central peak common on the moon; the other a huge valley—called Ithaca Chasma—that is 63 mi (100 km) wide, 2.5 mi (4 km) deep, and 1,250 mi (2,000 km) long, stretching three quarters of the way around Tethys's circumference. Tethys is co-orbital with two other moons; that is, they orbit Saturn at the same distance as Tethys but precede (TelestoTelesto
, in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn XIII (or S13), Telesto is an irregularly shaped (nonspherical) body measuring about 21 mi (34 km) by 17 mi (28 km) by 16 mi (26 km); it orbits Saturn at a mean distance of
..... Click the link for more information. ) and follow (CalypsoCalypso,
in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn XIV (or S14), Calypso is a small, irregularly shaped (nonspherical) body measuring about 21 mi (34 km) by 13.5 mi (22 km) by 13.
..... Click the link for more information. ) Tethys by about 60°.
Tethys(teeth -iss) The largest of the inner satellites of Saturn, having a diameter of 1050 km. It was discovered in 1684 by Giovanni Domenico Cassini. In size it is virtually the twin of the satellite Dione. Its low density of 1.2 g cm–3 indicates that it is probably made up mainly of water ice. Tethys has a feature currently unique in the Solar System: a huge canyon system, Ithaca Chasma, extending around the globe from near the north pole down to the equator and extending farther to the south pole; its average width is 100 km and its depth is 4–5 km. There is also an enormous crater, Odysseus, 400 km in diameter at 30° N latitude, 130° W longitude: its diameter is 40% that of the satellite and greater than the diameter of Mimas. The remainder of the surface is covered in craters of a range of sizes up to 20–50 km, indicating that Tethys has suffered intense bombardment in its history. Two much smaller satellites are held in the same orbit as Tethys. Telesto travels about 60° ahead of it and Calypso follows it at the same angular distance. Telesto and Calypso are known as the Tethys Trojans. See also Table 2, backmatter.
a satellite of the planet Saturn. Its diameter is approximately 1,000 km and its mean distance from the center of the planet is 295,000 km. Tethys was discovered in 1684 by the French astronomer G. Cassini.
(named for Thetis, the ancient Greek goddess of the sea), an ancient ocean basin that, during the Mesozoic period, separated the European and Siberian continents from the African and peninsular Indian continents and connected the Atlantic and Pacific oceans. The name was proposed in the late 19th century by the Austrian geologist E. Suess.
The region occupied by the Tethys had formerly been called the Central Mediterranean Region by M. Neumayr; in the French literature it was called the Mésogée. The term “Tethys” was subsequently extended to the Paleozoic ocean of the same region, called the Paleotethys. The Paleogene-Neogene seas that are remnants of the Mesozoic Tethys are called the Paratethys; the present Mediterranean, Black, and Caspian seas are a relict of Paratethys.