Universal Time
<time, standard> (UT) The mean solar time along the prime meridian (0
longitude) that runs through the Greenwich Observatory outside of London, UK,
where the current system originated. UT is tied to the rotation of the Earth in
respect to the fictitious "mean Sun".
Greenwich Mean Time (GMT) was measured from Greenwich mean midday until 1925
when the reference point was changed from noon to midnight and the name changed
to "Universal Time".
There are three separate definitions, UT0, UT1, and UT2, depending on which
corrections have been applied to the Earth's motion. Coordinated Universal Time
is kept within 0.9 seconds of UT1, by addition of leap seconds to International
Atomic Time.
(2001-08-02)
Nearby terms:
Universal Resource Locator « Universal Serial Bus «
universal thunk « Universal Time » Universal
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