10 Facts About UTC


UTC was first officially adopted as CCIR Recommendation 374, Standard-Frequency and Time-Signal Emissions, in 1963, but the official abbreviation of UTC and the official English name of Coordinated Universal Time were not adopted until 1967.

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System has been adjusted several times, including a brief period during which the time-coordination radio signals broadcast both UTC and "Stepped Atomic Time " before a new UTC was adopted in 1970 and implemented in 1972.

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UTC is used in many Internet and World Wide Web standards.

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Weather forecasts and maps all use UTC to avoid confusion about time zones and daylight saving time.

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Since 1972, UTC is calculated by subtracting the accumulated leap seconds from International Atomic Time, which is a coordinate time scale tracking notional proper time on the rotating surface of the Earth .

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Such approximations are designated UTC, where k is an abbreviation for the time laboratory.

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Therefore, telemetry from clocks with a known relation to the geoid is used to provide UTC when required, on locations such as those of spacecraft.

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Time zone using UTC is sometimes denoted UTC±00:00 or by the letter Z—a reference to the equivalent nautical time zone, which has been denoted by a Z since about 1950.

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On electronic devices which only allow the time zone to be configured using maps or city names, UTC can be selected indirectly by selecting cities such as Accra in Ghana or Reykjavik in Iceland as they are always on UTC and do not currently use Daylight Saving Time .

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UTC would be more and more ahead of UT; it would coincide with local mean time along a meridian drifting slowly eastward .

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