Who invented international date line

Most of these deviations are the result of practical considerations, such as to avoid splitting a country into two time zones, or for political and economic reasons. Although the islands are only separated by the narrowest of margins — just 2 miles 3. It then tracks back, following the degree meridian south again for several thousand miles, passing west of the Hawaiian Islands and east of the independent nation of the Marshall Islands, until reaching the Pacific island nation of Kiribati.

This deviation reaches nearly as far east as the degree meridian and forms a very large and noticeable hammerhead-looking configuration.

Kiribati, which received its independence from the United Kingdom in , is a group of 33 mostly uninhabited islands and atolls that span a vast area encompassing no less than 1. This caused considerable political and economic hardships as the nation tried to conduct normal everyday business with one half of its nation a day ahead and the other a day behind.

In , Kiribati decided it had had enough of this arrangement, and seeking greater economic ties with Australia and New Zealand, extended the IDL eastward to encompass the nation's far-flung eastern islands, thus creating the odd configuration. Shifting the date line is a relatively easy matter, the BBC reported. The country can decide for itself. It then swerves back sharply toward the degree meridian, but does not follow the meridian's exact path.

Instead, it stays parallel to the meridian, keeping to the east of the line so that Tonga, the Kermadec Islands and New Zealand are all east of the IDL. It follows this path until reaching Antarctica, which has multiple time zones. The IDL is not drawn into Antarctica on most maps.

In essence, it is a more sophisticated version of GMT because it is still based on the zero degrees of latitude that passes through Greenwich but relies on atomic clocks. These devices, invented in the s, are incredibly accurate and are based solely on Earth's rotation. The clocks take into account slight variations in the Earth's rotation rate that can cause timekeeping to vary.

This article has been updated from a previous version written by Dan Helm in Tom Garlinghouse is a journalist specializing in general science stories. He has a Ph. This description is based on the most common understanding of the de facto International Date Line. Begin typing your search term above and press enter to search.

Press ESC to cancel. Useful tips. Two adjustments of the date line took place in near the island chain of Hawaii and between Samoa and the Chatham Islands. By the non-existence of these islands had become firmly established and the date line was straightened out at that point.

North of the Bering Strait, at the latitude of Wrangel Island Ostrov Vrangelya which separates the East-Siberian Sea from the Chukchi Sea, the date line experienced some local adjustments during the early s. They did this to facilitate trade with Australia and New Zealand , and Tokelau followed Samoa for the same reasons. Unlike the International Date Line, whose course is determined by the countries bordering it, the Nautical Date Line is defined by international agreements.

Topics: Timekeeping , Time Zone , Geography.