prime meridian

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Related to prime meridians: Meridian Line

prime meridian,

meridian that is designated zero degree (0°) longitude, from which all other longitudes are measured. By international convention, it passes through the original site of the Royal Observatory in Greenwich, England; for this reason, it is sometimes called the Greenwich meridian. 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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, the standard basis for determining time throughout the world, is civil timecivil time,
local time based on universal time. Civil time may be formally defined as mean solar time plus 12 hr; the civil day begins at midnight, while the mean solar day begins at noon.
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 measured at the prime meridian.

prime meridian

The arbitrary circle of zero longitude on the Earth or some other planet or mapped celestial body. The Earth's prime meridian is the Greenwich meridian.

Prime Meridian

 

(or zero meridian), the terrestrial meridian that passes through Greenwich, the site of the old Royal Observatory. The prime meridian is the starting point for the calculation of geographic longitude and is the central meridian of the zero time zone. Local mean solar time at the prime meridian is widely used in astronomy (so-called universal time).

prime meridian

[′prīm mə‚rid·ē·ən]
(geodesy)
The meridian of longitude 0°, used as the origin for measurement of longitude; the meridian of Greenwich, England, is almost universally used for this purpose.

prime meridian

The meridian passing through Greenwich (UK). It is longitude 0°. See longitude.

prime meridian

the 0° meridian from which the other meridians or lines of longitude are calculated, usually taken to pass through Greenwich
References in periodicals archive ?
Today's travelers and scientists owe much to the fact that, despite difficulties (including an attempted bombing), the 1884 International Meridian Conference agreed upon and established a single prime meridian to make the world a safer, more easily measurable place.
11) Around 1600, Blaeu designed his maps and globes with a prime meridian passing over the Azores, usually the islands of Corvo and Flores in the Western Azores.
Blaeu published three small terrestrial globes using the Corvo and Flores prime meridian before 1620.
It remained this way until the reigns of Charles II of England and Louis XIV of France, each of whom wanted the privilege of having the prime meridian cross his kingdom.

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