Columbia Encyclopedia

Search results

58 results found

Graham, George

(Encyclopedia)Graham, George, 1674?–1751, English instrument maker. A clockmaker by trade, Graham designed clocks and watches that earned him membership in the Royal Society and were still manufactured into the p...

Phoebe, in astronomy

(Encyclopedia)Phoebe fēˈbē [key], in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn IX (or S9), Phoebe is 137 mi (220 km) in diameter, orbits Saturn at a mean distance ...

Encke, Johann Franz

(Encyclopedia)Encke, Johann Franz yōˈhän fränts ĕngˈkə [key], 1791–1865, German astronomer. He was assistant (1816–22) and director (1822–25) of the observatory at Seeberg (near Gotha) and director (fr...

Flamsteed, John

(Encyclopedia)Flamsteed, John flămˈstēd [key], 1646–1719, English astronomer. He was appointed (1675) astronomer royal by King Charles II and carried on his researches at Greenwich Observatory. Over his protes...

ultraviolet astronomy

(Encyclopedia)ultraviolet astronomy, study of celestial objects by means of the ultraviolet radiation they emit, in the wavelength range from about 90 to about 350 nanometers. Ultraviolet (UV) line spectrum measure...

Roche limit

(Encyclopedia)Roche limit, the closest distance that a celestial body held together only by its own gravity can come to a planet without being pulled apart by the planet's tidal (gravitational) force. This distance...

Scholz's star

(Encyclopedia)Scholz's star, dim binary star system, consisting of a red dwarf and brown dwarf, in the constellation Monoceros, apparent magnitude 18.3. The red dwarf is a tiny star, with less than ten percent the ...

Arrokoth

(Encyclopedia)Arrokoth, trans-Neptunian object in the Kuiper Belt (see comet). First observed by the Hubble Space Telescope in 2014 and later nicknamed Ultima Thule (until its official naming in late 2019), it beca...

Bond, George Phillips

(Encyclopedia)Bond, George Phillips, 1825–65, American astronomer, b. near Boston, grad. Harvard, 1845. He became the assistant of his father, William Cranch Bond, and in 1859 succeeded him as director of the Har...

Star of Bethlehem, in the Gospels

(Encyclopedia)Star of Bethlehem, name given to the luminous celestial object rising in the sky that, as related in the Gospel of Matthew, led the Wise Men of the East to the manger in Bethlehem where Jesus was born...

Browse by Subject