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Astro*Dictionary by Michael Erlewine

 

 

 

 

3 articles for "International"

International Atomic Time   TAI [Astro*Index]

The most precise timescale currently available. It uses an atomic clock and was adopted on January 1, 1972 for all timing purposes. TAI is of greater precision than can be derived from astronomical observations. UTC (Coordinated Universal Time), which is used for civil time distribution, is derived from TAI.

See also:
♦ Time Zone ♦ Civil Time
International Date Line   IDL [Astro*Index]

An irregular political boundary that roughly follows the Earth's 180°-meridian of longitude (12 hours away from the Greenwich Meridian). The notation IDLE and IDLW are used to denote the standard time zones on the east and west sides of the same boundary. Time reckoned in these two zones must differ by 24 hours. (This result is easily demonstrated by starting on the Greenwhich Meridian at noon and moving both eastward and westward to the IDL. When a traveler crosses it from east to west, his or her clock must be advanced by a full day; thus noon Tuesday would become noon Wednesday. For a traveler crossing it from west to east, the clock is set back a full day.

See also:
♦ Greenwich Meridian ♦ Standard Time
International Date Line   IDL [Munkasey M.]

A line which generally follows the Earth's 180th degree of longitude. It is at this line that a traveler going from East to West would subtract one day, while a traveler going from West to East would add one day of time. This action is to compensate for the addition and subtraction of hours when crossing the different time zone boundaries.

See also:
♦ Greenwich Meridian ♦ Standard Time

 

Astro*Index Copyright © 1997 Michael Erlewine