Glossary term: International Date Line

Description: The International Date Line is a specific meridian which roughly follows the meridian of longitude 180°. The International Date Line passes north–south between Russia and Alaska, through the Pacific Ocean including parts of Micronesia and Polynesia, and to the east of Australia/New Zealand before reaching the South Pole on Antarctica. The International Date Line marks the boundary where calendar dates change by one. Therefore, regions to the west of the International Date line are one calendar day ahead of regions to the east.

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The OAE Multilingual Glossary is a project of the IAU Office of Astronomy for Education (OAE) in collaboration with the IAU Office of Astronomy Outreach (OAO). The terms and definitions were chosen, written and reviewed by a collective effort from the OAE, the OAE Centers and Nodes, the OAE National Astronomy Education Coordinators (NAECs) and other volunteers. You can find a full list of credits here. All glossary terms and their definitions are released under a Creative Commons CC BY-4.0 license and should be credited to "IAU OAE".