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Greenwich Mean Time updated with leap seconds

Greenwich Mean Time updated with leap seconds

(UTC, World Time) The standard time common toevery place in the world. UTC is derived from InternationalAtomic Time (TAI) by the addition of a whole number of "leapseconds" to synchronise it with Universal Time 1 (UT1), thusallowing for the eccentricity of the Earth's orbit, therotational axis tilt (23.5 degrees), but still showing theEarth's irregular rotation, on which UT1 is based.Coordinated Universal Time is expressed using a 24-hour clockand uses the Gregorian calendar. It is used in aeroplaneand ship navigation, where it also sometimes known by themilitary name, "Zulu time". "Zulu" in the phonetic alphabetstands for "Z" which stands for longitude zero.UTC was defined by the International Radio ConsultativeCommittee (CCIR), a predecessor of the ITU-T. CCIRRecommendation 460-4, or ITU-T Recommendation X.680 (7/94),contains the full definition.The language-independent international abbreviation, UTC, isneither English nor French. It means both "CoordinatedUniversal Time" and "Temps Universel Coordonné".BIPM(http://www.bipm.org/enus/5_Scientific/c_time/time_1.html).The Royal Observatory Greenwich(http://rog.nmm.ac.uk/leaflets/time/time.html).History of UTC and GMT(http://ecco.bsee.swin.edu.au/chronos/GMT-explained.html).U.S. National Institute of Standards & Technology(http://its.bldrdoc.gov/fs-1037/dir-009/_1277.htm).UK National Physical Laboratory(http://npl.co.uk/npl/ctm/time_scales.html).US Naval Observatory(http://tycho.usno.navy.mil/systime.html).International Telecommunications Union(http://itu.int/radioclub/rr/arts02.htm).Earth's irregular rotation(http://foldoc.org/pub/misc/earth_rotation).