UTC: Forskelle mellem versioner

'''Koordineret universaltid''' ({{lang-fr|temps universel coordonné}}, '''UTC''') er [[Verden]]s primære [[international]]e [[tidsstandard]] til brug for regulering af [[ur]]e og [[klokken|klokkeslæt]].<ref>[https://www.timeanddate.com/time/aboututc.html timeanddate.com: UTC – The World's Time Standard] Citat: "...UTC is the time standard commonly used across the world. The world's timing centers have agreed to keep their time scales closely synchronized - or coordinated - therefore the name Coordinated Universal Time...", [https://web.archive.org/web/20200925105034/https://www.timeanddate.com/time/aboututc.html backup]</ref><ref>[https://copradar.com/utctime/ copradar.com: Coordinated Universal Time] Citat: "...Mean solar time -- a measurement of the Earth's rotation with respect to the 'fictitious' mean sun...second -- One second (1 s or 1 sec.) is the duration of 9,192,631,770 periods of radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom (Cs)...UT1 -- UT0 corrected for polar motion (widely used)...UTC -- civil atomic time scale on or about the Greenwich meridian kept within 0.9 seconds of UT1...", [https://web.archive.org/web/20200925105034/https://www.timeanddate.com/time/aboututc.html backup]</ref> Koordineret universaltid kaldes på dansk også '''universel tid''' eller undertiden '''verdenstid'''. Tidsstandarden er for de fleste anvendelser det samme som [[Greenwich Mean Time]] (GMT), men GMT er ikke længere præcist defineret af videnskaben.