International date line Upsc

International date line and its coordinates

  • Latitude: 0° 00′ 0.00″ N
  • Longitude: -180° 00′ 0.00″ W


It is an imaginary line dividing the surface of the earth, which runs from the North Pole to the South Pole and demarcates the border between one calendar day and the next.

It serves as the “line of demarcation” between the two calendar days.

International date line upsc
International date line By –, Public Domain,

Prime meridian

Is the Prime Meridian and the International Date Line the same thing?

The Prime Meridian separates the eastern Hemisphere from the Western Hemisphere. International Date Line is Halfway around the world, at 180-degree Longitude.

The prime meridian is present at 0 degrees Longitude.

What is the time difference between IDL and prime meridian?

The time difference between International Date Line and Prime Meridian is 12 Hours.

IDL Latitude and longitude

It passes through the Mid-Pacific Ocean and follows a 180-degree longitude North-South Line.


It is located halfway around the world from the Prime meridian. The Zero degrees longitude is present or established in Greenwich England in 1852.

International date line passes through

International date line passes through which countries?

It passes through Samoa, Tokelau, Wallis and Futuna, Fiji, Tonga, Tuvalu, and New Zealand the Kermadec Islands and the Chatham Islands are all west of IDL and have the same date.

American Samoa, Cook Islands, Niue, and French Polynesia are located east of IDL and one day behind.

International date line passes through which strait?

It passes most of its to 180 degrees of longitude, but it bends eastward through the Bering Strait. It does so to avoid dividing Siberia and then bends westwards to include the Aleutian Island with Alaska.

International date line and arctic circle
International date line on map By Another Matt (talk) – I (Another Matt (talk)) created this work entirely by myself, incorporating a map from , which is stated to be public domain, CC0,

International date line time zone

UTC−12:00 is an identifier for a time offset from UTC of −12:00. It is the last to enter a new year and is sometimes referred to as the International Date Line West time zone (IDLW).

International date line and arctic circle

The Arctic circle is close to 16,000 km and the area north of the Circle is roughly 20,000,000 km2 which covers almost 4% of Earth’s Surface.

The Arctic is derived from the word “arktikos”, which means bear in the Greek language. The “Ursa Major” Constellation is viewed in the Northern sky. The arctic circle region, where at least 1 day a year will receive sunshine all day during summer and the full one day or 24 will not receive any light and will be dark throughout the day.

The arctic circle passes through the Arctic Ocean, the Scandinavian Peninsula, North Asia, Northern America, and Greenland.

The countries in the Arctic circle are eight, they are Norway, Sweden, Finland, Russia, the United States, Canada, Denmark, and Iceland.

IDL also separates Russia and the US off Alaska’s West Coast.

The Big Diomede Islands in Russia and Little Diomede in the USA are apart by 3.8 Km of the sea and IDL runs midway between them.

The Arctic and Antarctic Circles are the parallels of latitude that are roughly 66.5 degrees (66° 33′ 44″ (or 66.5622°).

Arctic circle latitude

Arctic Circle, parallel, or line of latitude around the Earth, at approximately 66°30′ N. This is due to the Earth’s inclination of about 23 1/2° to the vertical. This marks the southern limit of the area within which, for one day or more each year.

As a result, Sun does not set (about June 21) or rise (about December 21).


a. Where is the dateline located?

The dateline is located, at a 0-degree longitude line in Greenwich, England. It was established in 1884 and passed through the mid-pacific ocean.

b.What is the longitude of the international date line?

It is 0-degree Longitude. It is the starting point.

c. Antarctic circle passes through which countries?

The country that passes through the Antarctic circle, is Antarctica only. But Antarctica is not a country, it is the southernmost continent.


0 0 votes
Article Rating
Notify of
Inline Feedbacks
View all comments
* * All the Notes in this blog, are referred from Tamil Nadu State Board Books and Samacheer Kalvi Books. Kindly check with the original Tamil Nadu state board books and Ncert Books.
Would love your thoughts, please comment.x
%d bloggers like this: