The Chamorro Time Zone, formerly the Guam Time Zone, is a United States time zone which observes

standard time Standard time is the synchronisation of clocks within a geographical region to a single time standard, rather than a local mean time standard. Generally, standard time agrees with the local mean time at some meridian that passes through the r ...

ten hours ahead of

Coordinated Universal Time Coordinated Universal Time or UTC is the primary time standard by which the world regulates clocks and time. It is within about one second of mean solar time (such as UT1) at 0° longitude (at the IERS Reference Meridian as the currently used ...

( UTC+10:00). The clock time in this zone is based on the

mean solar time Solar time is a calculation of the passage of time based on the position of the Sun in the sky. The fundamental unit of solar time is the day, based on the synodic rotation period. Two types of solar time are apparent solar time (sundial ti ...

of the

150th meridian east The meridian 150° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Asia, the Pacific Ocean, Australasia, the Southern Ocean, and Antarctica to the South Pole. The 150th meridian east forms a g ...

of the

Greenwich Observatory The Royal Observatory, Greenwich (ROG; known as the Old Royal Observatory from 1957 to 1998, when the working Royal Greenwich Observatory, RGO, temporarily moved south from Greenwich to Herstmonceux) is an observatory situated on a hill in G ...

. The zone includes the

U.S. territories Territories of the United States are sub-national administrative divisions overseen by the federal government of the United States. The various American territories differ from the U.S. states and tribal reservations as they are not sover ...

Guam Guam (; ch, Guåhan ) is an organized, unincorporated territory of the United States in the Micronesia subregion of the western Pacific Ocean. It is the westernmost point and territory of the United States (reckoned from the geographic cent ...

and the

Northern Mariana Islands The Northern Mariana Islands, officially the Commonwealth of the Northern Mariana Islands (CNMI; ch, Sankattan Siha Na Islas Mariånas; cal, Commonwealth Téél Falúw kka Efáng llól Marianas), is an unincorporated territory and commonw ...

, where the

Chamorro people The Chamorro people (; also CHamoru) are the indigenous people of the Mariana Islands, politically divided between the United States territory of Guam and the encompassing Commonwealth of the Northern Mariana Islands in Micronesia. Today, signif ...

are the original inhabitants. Since

Daylight Saving Time Daylight saving time (DST), also referred to as daylight savings time or simply daylight time (United States, Canada, and Australia), and summer time (United Kingdom, European Union, and others), is the practice of advancing clocks (typicall ...

(DST) is not observed anywhere in this zone, the time is always known as Chamorro Standard Time (ChST). The zone is two hours behind

Wake Island Time Zone {{Short description, UTC+12:00 The Wake Island Time Zone observes standard time by adding twelve hours to Coordinated Universal Time ( UTC+12:00). The clock time in this zone is based on the mean solar time of the 180th degree meridian east of th ...

and 15 hours ahead of North American

Eastern Time Zone The Eastern Time Zone (ET) is a time zone encompassing part or all of 23 states in the eastern part of the United States, parts of eastern Canada, the state of Quintana Roo in Mexico, Panama, Colombia, mainland Ecuador, Peru, and a small por ...

. As of March 8, 2020, it is the easternmost (farthest ahead) time zone shown on the U.S. government's time.gov webpage. Although Wake, Howland and Baker Islands are U.S. territories in more easterly time zones (that are not shown), they are uninhabited. Chamorro Standard Time shares the same time as

Australian Eastern Standard Time Australia uses three main time zones: Australian Western Standard Time (AWST; UTC+08:00), Australian Central Standard Time (ACST; UTC+09:30), and Australian Eastern Standard Time (AEST; UTC+10:00). Time is regulated by the individual state ...

. The State of

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...

also does not observe DST, so the CNMI, Guam and Queensland are on the same time year round.

Populated areas and major cities

Hagåtña, Guam Hagåtña (; ; formerly in English: Agana , in Spanish: Agaña) is the capital village of the United States territory of Guam. From the 18th through mid-20th century, it was Guam's population center, but today it is the second smallest of the ...

Saipan, Northern Mariana Islands Saipan ( ch, Sa’ipan, cal, Seipél, formerly in es, Saipán, and in ja, 彩帆島, Saipan-tō) is the largest island of the Northern Mariana Islands, a commonwealth of the United States in the western Pacific Ocean. According to 2020 est ...

History

The U.S. Congress formally created Chamorro Standard Time by federal Public Law 106-564 on December 23, 2000. Prior thereto, ''Guam'' Standard Time existed per territorial Public Law 5-25 (1959)Guam Code Annotated, Title 1, Section 1010
textPDF
. This statute is still on the territorial law books, though is preempted by the federal law. The Northern Mariana Islands, as part of the

Trust Territory of the Pacific Islands The Trust Territory of the Pacific Islands (TTPI) was a United Nations trust territory in Micronesia administered by the United States from 1947 to 1994. History Spain initially claimed the islands that later composed the territory of the Trus ...

, were not part of any American time zone prior to becoming a U.S. Commonwealth on January 1, 1978. But being directly north of Guam, they observed the same time.

References

{{reflist

Sources

Current time around the world
Time zones Time zones in the United States

Populated areas and major cities

History

See also

References

Sources