Columbia Encyclopedia

Search results

48 results found

Meridian

(Encyclopedia)Meridian mərĭdˈēən [key], city (1990 pop. 41,036), seat of Lauderdale co., E Miss., near the Ala. line; settled 1831, inc. 1860. It is an important rail and highway point and the trade and shippi...

celestial meridian

(Encyclopedia)celestial meridian, vertical circle passing through the north celestial pole and an observer's zenith. It is an axis in the altazimuth coordinate system. ...

prime meridian

(Encyclopedia)prime meridian, meridian that is designated zero degree (0°) longitude, from which all other longitudes are measured. By international convention, it passes through the site of the Royal Observatory ...

transit instrument

(Encyclopedia)transit instrument or transit, telescope devised to observe stars as they cross the meridian and used for determining time. Its viewing tube swings on a rigid horizontal axis restricting its movements...

Greenwich mean time

(Encyclopedia)Greenwich mean time or Greenwich meridian time (GMT), the former name for mean solar time at the site of the Royal Observatory in Greenwich, England, which is located on the prime meridian. In 1925 th...

longitude

(Encyclopedia)longitude lŏnˈjĭto͞odˌ [key], angular distance on the earth's surface measured along any latitude line such as the equator east or west of the prime meridian. A meridian of longitude is an imagin...

compass

(Encyclopedia)compass. 1 In mathematics, an instrument for making circles and measuring distances. Frequently called a pair of compasses, it consists of two metal legs with one end of each attached to a pivot to fo...

Browse by Subject