Columbia Encyclopedia

Search results

500 results found

Juno, in astronomy

(Encyclopedia)Juno jo͞oˈnō [key], in astronomy, 3d asteroid to be discovered. It was found in 1804 by C. Harding. It has a diameter of c.120 mi (190 km). Its average distance from the sun is 2.67 astronomical un...

Jupiter, in astronomy

(Encyclopedia)Jupiter jo͞oˈpətər [key], in astronomy, 5th planet from the sun and largest planet of the solar system. Astronomers have discovered 79 satellites orbiting Jupiter, but five of those, small sate...

Janus, in astronomy

(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...

Atlas, in astronomy

(Encyclopedia)Atlas, in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn XV (or S15), Atlas is a small, irregularly shaped (nonspherical) body measuring about 25 mi (40 km) ...

Metis, in astronomy

(Encyclopedia)Metis mēˈtĭs [key], in astronomy, one of the 39 known moons, or natural satellites, of Jupiter. ...

Naiad, in astronomy

(Encyclopedia)Naiad, in astronomy, one of the natural satellites, or moons, of Neptune. ...

Neptune, in astronomy

(Encyclopedia)Neptune, in astronomy, 8th planet from the sun at a mean distance of about 2.8 billion mi (4.5 billion km) with an orbit lying between those of Uranus and the dwarf planet Pluto; its period of revolut...

Mars, in astronomy

(Encyclopedia)Mars, in astronomy, 4th planet from the sun, with an orbit next in order beyond that of the earth. Mars has two natural satellites, discovered by Asaph Hall in 1877. The innermost of these, Phobos...

Mimosa, in astronomy

(Encyclopedia)Mimosa or Beta Crucis bāˈtə kro͞oˈsĭs [key], bright star in the constellation Crux (Southern Cross); 1992 position R.A. 12h47.3m, Dec. −59°39′. It is sometimes called Becrux, from its Bayer...

Mercury, in astronomy

(Encyclopedia)Mercury, in astronomy, nearest planet to the sun, at a mean distance of 36 million mi (58 million km); its period of revolution is 88 days. Mercury passes through phases similar to those of the moon a...