Columbia Encyclopedia

(Encyclopedia) Hyades hīˈədēz [key], in astronomy, open star cluster in the constellation Taurus, located immediately to the right of the bright star Aldebaran. The cluster is about 130 light-years from the eart...

(Encyclopedia) Janus jāˈnəs [key], in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn X (or S10), Janus is an irregularly shaped (nonspherical) body measuring about 122 m...

(Encyclopedia) Tethys tēˈthĭs [key], in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn III (or S3), Tethys is 659 mi (1060 km) in diameter, orbits Saturn at a mean dista...

(Encyclopedia) Dione dīōˈnē [key], in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn IV (or S4), Dione is 695 mi (1,120 km) in diameter, orbits Saturn at a mean distanc...

(Encyclopedia) radar astronomy, application of radar to the determination of distances and planetary features within the solar system, such as rotation rates. A short burst of radio waves is transmitted in the direc...

(Encyclopedia) Iapetus īăpˈĭtəs [key], in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn VIII (or S8), Iapetus is 907 mi (1460 km) in diameter, orbits Saturn at a mean...

(Encyclopedia) Saturn, in Roman religion and mythology, god of harvests, later identified with the Greek Kronos. Little is known of the origins of his cult. His reign was regarded as the Golden Age. He was the husba...

(Encyclopedia)  CE5 Phases of the moon phase, in astronomy, the measure of how much of the illuminated surface of a planet or satellite can be seen from a point at a distance from that body; the term is most ofte...

(Encyclopedia) Vesta vĕsˈtə [key], in astronomy, the fourth asteroid to be discovered. It was found in 1807 by H. Olbers. It is the third largest asteroid in size, with a diameter of c.326 mi (525 km). Its averag...

(Encyclopedia) dwarf planet, a nonluminous body of rock or gas that orbits the sun and has a rounded shape due to its gravity. Unlike a planet, a dwarf planet is not capable of clearing its orbit of smaller objects ...