civil time


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Related to civil time: Zulu time, Local Civil Time

civil time,

local timetime,
sequential arrangement of all events, or the interval between two events in such a sequence. The concept of time may be discussed on several different levels: physical, psychological, philosophical and scientific, and biological.
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 based on universal timeuniversal time
(UT), the international time standard common to every place in the world, it nominally reflects the mean solar time along the earth's prime meridian (renumbered to equate to civil time).
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. Civil time may be formally defined as mean solar timesolar time,
time defined by the position of the sun. The solar day is the time it takes for the sun to return to the same meridian in the sky. Local solar time is measured by a sundial.
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 plus 12 hr; the civil day begins at midnight, while the mean solar day begins at noon. Civil time is occasionally adjusted by one-second increments to ensure that the difference between a uniform timescale defined by atomic clocksatomic clock,
electric or electronic timekeeping device that is controlled by atomic or molecular oscillations. A timekeeping device must contain or be connected to some apparatus that oscillates at a uniform rate to control the rate of movement of its hands or the rate of
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 does not differ from the earth's rotational time by more than 0.9 seconds. Coordinated universal time (UTC), an atomic time, is the basis for civil time. Civil time is usually not used, since it depends on the observer's longitude; instead, standard timestandard time,
civil time used within a given time zone. The earth is divided into 24 time zones, each of which is about 15° of longitude wide and corresponds to one hour of time. Within a zone all civil clocks are set to the same local solar time.
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, which is the same throughout a given time zone, is generally adopted.

civil time

[¦si·vəl ¦tīm]
(astronomy)
Solar time in a day (civil day) that begins at midnight; may be either apparent solar time or mean solar time.