ENCYCLOPEDIC ENTRY

ENCYCLOPEDIC ENTRY

date line

date line

Encyclopedic entry. The date line, also called the International Date Line, is a boundary from which each calendar day starts. Areas to the west of the date line are one calendar day ahead of areas to the east.

Grades

5 - 12+

Subjects

Geography, Physical Geography

















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Morgan Stanley

The date line, also called the International Date Line, is a boundary from which each calendar day starts. Areas to the west of the date line are one calendar day ahead of areas to the east.

The date line runs from the North Pole to the South Pole through the Pacific Ocean. It is not a straight line, however. The date line curves around several landmasses. For example, it curves around the islands that make up the nation of Kiribati, so that all regions of the country remain on the same day. The date line makes a big detour between Asia and North America in the Bering Strait. Cape Dezhnev, Russia, is always a day ahead of Cape Prince of Wales, Alaska, even though the landmasses are less than 80 kilometers (50 miles) apart.

The date line, which roughly follows the 180-degree meridian, is about halfway around the globe from the prime meridian, which measures 0-degrees longitude.

Fast Fact

Hawai'i and Kiribati
The islands of the U.S. state of Hawai'i lie almost directly north of the islands of the nation of Kiribati in the Pacific Ocean. They fall within the same lines of longitude.
However, because of a curve the date line makes around Kiribati, they are a day apart.

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Writers
Kim Rutledge
Melissa McDaniel
Santani Teng
Hilary Hall
Tara Ramroop
Erin Sprout
Jeff Hunt
Diane Boudreau
Hilary Costa
Illustrators
Mary Crooks, National Geographic Society
Tim Gunther
Editors
Jeannie Evers, Emdash Editing, Emdash Editing
Kara West
Educator Reviewer
Nancy Wynne
Producer
National Geographic Society
other
Last Updated

October 19, 2023

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