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Nine Time Zones: A Trace of American Empire?

How the United States ended up with one of the highest numbers of time zones for a single country.

July 1, 2018

1. The United States, the third-largest country by land area (after Russia and China) has nine time zones.

2. This number is due not to its core area, but rather to its widely dispersed late 19th century colonial phase and 20th century acquisitions.

3. In the continental United States, there are four time zones. Then there is a fifth for mainland Alaska and a sixth for Hawaii and Alaska’s Aleutian Islands.

4. A seventh U.S. time zone is for the two U.S. Caribbean territories (Puerto Rico and U.S. Virgin Islands), which recently suffered severe hurricane damage.

5. Finally, there are eighth and ninth U.S. time zones covering the three U.S. Pacific territories (American Samoa, Guam and Northern Mariana Islands).

6. This is similar to the United Kingdom, which also has nine time zones, largely due to its overseas territories.

7. For most of human history, time was reckoned or measured based on the local position of the sun.

8. This varied by season and from one region of a country to another. Eventually, more standardized time zone systems were introduced.

9. Today, the United States has nearly as many time zones as Russia (11) and France (12), the world leader.

10. U.S. mainland time is zoned much more effectively for local purposes than China, which uses just one zone for a similar breadth.

Sources: The Globalist Research Center, U.S. National Institute of Standards & Technology

Takeaways

The US, the third-largest country by land area (after Russia and China) has nine time zones.

For most of human history, time was reckoned or measured based on the local position of the sun.

U.S. mainland time is zoned much more effectively for local purposes than China, which uses just one zone for a similar breadth.