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equation of time

(Encyclopedia)equation of time: see solar time. ...

apparent solar time

(Encyclopedia)apparent solar time: see solar time. ...

equal-time rule

(Encyclopedia)equal-time rule, a Federal Communications Commission rule that requires equal air time for all major candidates competing for political office. It was preceded by the fairness doctrine, abolished in 1...

time , in music

(Encyclopedia)time, in music: see tempo; meter; rhythm; syncopation; metronome and musical notation. ...

time and motion study

(Encyclopedia)time and motion study, analysis of the operations required to produce a manufactured article in a factory, with the aim of increasing efficiency. Each operation is studied minutely and analyzed in ord...

period, in geologic time

(Encyclopedia)period, unit of time on the geologic timescale. Periods are shorter than an era and longer than an epoch. Periods are of variable length, generally lasting tens of millions of years, with characterist...

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 ...

Dyson, Sir Frank Watson

(Encyclopedia)Dyson, Sir Frank Watson dīˈsən [key], 1868–1939, English astronomer, b. Ashby-de-la-Zouch, grad. Cambridge. He was astronomer royal of Scotland (1905–10) and of England (from 1910). As director...

De Niro, Robert Anthony Jr.

(Encyclopedia) De Niro, Robert Anthony, Jr., 1943-, American film actor and director, b. New York, N.Y. Both of De Niro’s parents were painters; De Niro was raised...

tropical year

(Encyclopedia)tropical year, time between successive vernal equinoxes; 365 days, 5 hr, 48 min, 46 sec of mean solar time (see solar time). The tropical year is the basis of the year used in the Gregorian calendar. ...