| 1. | an ancient Roman god of agriculture, the consort of Ops, believed to have ruled the earth during an age of happiness and virtue, identified with the Greek god Cronus. |
| 2. | Astronomy. the planet sixth in order from the sun, having an equatorial diameter of 74,600 mi. (120,000 km), a mean distance from the sun of 886.7 million mi. (1427 million km), a period of revolution of 29.46 years, and 21 known moons. It is the second largest planet in the solar system, encompassed by a series of thin, flat rings composed of small particles of ice. |
| 3. | Alchemy. the metal lead. |
| 4. | a U.S. space-vehicle booster developing from 2 million to 9 million lb. (900,000 to 4 million kg) of thrust for launching satellites, probes, and spaceships. |
| Saturn (sāt'ərn) Pronunciation Key
The sixth planet from the Sun and the second largest, with a diameter about ten times that of Earth. Saturn is a gas giant that is almost as large as Jupiter in diameter but with only about 30 percent of Jupiter's mass. Its mainly gaseous composition together with its rapid axial rotation (it rotates once every 10.5 hours) cause a noticeable flattening at the poles and a prominent equatorial bulge. Saturn is encircled by a large, flat system of rings made up of rock fragments and tiny ice crystals, first observed by Galileo in 1610. The rings are believed to be unstable and therefore likely of recent origin; they may have been formed from bodies such as asteroids or moons that were shattered as they approached closer than the Roche limit. Saturn has numerous moons, of which the largest is Titan, the second largest moon in the solar system after Jupiter's Ganymede and larger than both Mercury and Pluto. See Table at solar system. |