Date Line

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Related to Date Line: deadline, International Date Line

Date Line


an arbitrary line drawn on the earth’s surface to demarcate places where the time of day is the same but the date differs by one full day. The date line coincides with the 180th meridian for most of its length, departing in places to avoid passing over dry land. East of the date line it is one day earlier than it is to the west. The date line serves to maintain a correct count of days of the month when traveling.

The traveler moving eastward passes through points where clocks indicating local (or zone) time show an ever-increasing time reading as compared to the local time at the starting point. By gradually setting his watch ahead, the traveler will have gained a day at the end of a journey around the world. Conversely, if the traveler makes his journey around the world from east to west he will have lost a day at the end of the journey. To resolve this problem, ships or airplanes crossing the date line from west to east set the date back by one day. For instance, if they approach the date line at ten o’clock on May 2, after crossing the line they will assume that it is ten o’clock on May 1. In traveling from east to west one day is added to the calendar date, so that if the date line is approached at ten o’clock on May 2, the time is assumed to be ten o’clock on May 3 after the date line has been crossed.

international date line

international date line
The Greenwich antimeridian, or 180° longitude. The international date line, however, does not follow the Greenwich antimeridian exactly but is distorted to place inhabited areas definitely on one side or the other of the line to avoid a difference in date in an inhabited area. Also called a calendar line or a date line.
References in periodicals archive ?
The imaginary International Date Line passes through the Pacific near the 180-degree meridian and is not set by an international treaty or organization.
The exact course of the International Date Line is jagged as individual nations and territories in the vicinity can set their own time zones and thus decide on which side of the line they fall.
The third part focuses on the difficult concept of The International Date Line, the meridian opposite Greenwich's, and its implementation.
AO: The Pacific Ocean from CONUS West Coast to the International Date Line.
Instead the team had to content itself by stopping at the International Date Line, which runs between the islands of Little Diomede, a part of US territory, and Big Diomede, which belongs to Russia.
wine-rose), Out of this World (cinnamon), Russian to a Party (deep sparkling burgundy), Mauve-a-rita, Por Favor (mauve), Grape Wall of China (amethyst), Int'l Date Line (dark brown), 20 Candles on My Cake (cherry-red) and Matadore Red (crimson).
We note with interest this news item, bearing a New York date line.
With its proximity just west of the international date line, the city will be warmed by the sun of the new millennium some 18 hours before frosty New Yorkers grab one another for a midnight kiss.
Our unease with the report began with two words in the date line, "Reno, Nevada.
For most of its north-south journey through the Pacific the date line follows the 180 degree meridian -- east of this line is one day earlier than it is to the west -- but it zig-zags around land masses for obvious reasons; if it didn't do so, their inhabitants would find themselves living in different days of the week.
Yes, and I thought it would be interesting if between the ship and the island there was the date line, so I complicated space with that.
A typhoon is essentially a hurricane-class storm occurring in the North Pacific, west of the International Date Line.