The Chamorro Time Zone, [1] formerly the Guam Time Zone, is a United States time zone which observes standard time ten hours ahead of Coordinated Universal Time (UTC+10:00). The clock time in this zone is based on the mean solar time of the 150th meridian east of the Greenwich Observatory.
The zone includes the U.S. territories of Guam and the Northern Mariana Islands, where the Chamorro people are the original inhabitants. Since Daylight Saving Time (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 and 15 hours ahead of North American Eastern Time Zone. As of March 19, 2024 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. The State of Queensland also does not observe DST, so the Commonwealth of the Northern Mariana Islands (CNMI), Guam and Queensland are on the same time year round.
Until the end of 1844, Guam and Mariana Islands belonged to Captaincy General of the Philippines, which followed the date of the western hemisphere on their island, placing them on the eastern side of the International Date Line (IDL). At the end of Monday, December 30, 1844, both Guam and Mariana Islands continued directly to Wednesday, January 1, 1845, effectively removing Tuesday, December 31, 1844 from the calendar to follow the eastern hemisphere on the west side of the IDL and realign themselves from American to Asian dates.[ citation needed ]
Before time zones were introduced, every place used local observation of the sun to set its clocks, which meant that every location used a different local mean time based on its longitude. For example, Hagåtña, the capital of Guam at the time, at longitude 144°45′E, had a local time equivalent to GMT-14:21 under the date of the western hemisphere and GMT+09:39 under the eastern hemisphere.[ citation needed ]
In 1901, "Guam Standard Time" was established within the United States as GMT+10:00.[ citation needed ]
The U.S. Congress formally created Chamorro Standard Time by federal Public Law 106-564 on December 23, 2000. Previously, Guam Standard Time existed per territorial Public Law 5-25 (1959). [2] This statute is still on the territorial law books, although it is preempted by the federal law.[ citation needed ]
The Northern Mariana Islands, as part of the Trust Territory of the Pacific Islands, were not part of any American time zone prior to becoming a U.S. Commonwealth on January 1, 1978. Being directly north of Guam, however, they observed the same time.[ citation needed ]
The history of Guam starts with the early arrival around 2000 BC of Austronesian people known today as the Chamorro Peoples. The Chamorus then developed a "pre-contact" society, that was colonized by the Spanish in the 17th century. The present American rule of the island began with the 1898 Spanish–American War. Guam's history of colonialism is the longest among the Pacific islands.
The Northern Mariana Islands, officially the Commonwealth of the Northern Mariana Islands, is an unincorporated territory and commonwealth of the United States consisting of 14 islands in the northwestern Pacific Ocean. The CNMI includes the 14 northernmost islands in the Mariana Archipelago; the southernmost island, Guam, is a separate U.S. territory. The Northern Mariana Islands were listed by the United Nations as a non-self governing territory until 1990.
A time zone is an area which observes a uniform standard time for legal, commercial and social purposes. Time zones tend to follow the boundaries between countries and their subdivisions instead of strictly following longitude, because it is convenient for areas in frequent communication to keep the same time.
Japan Standard Time, or Japan Central Standard Time, is the standard time zone in Japan, 9 hours ahead of UTC (UTC+09:00). Japan does not observe daylight saving time, though its introduction has been debated on several occasions. During World War II, the time zone was often referred to as Tokyo Standard Time.
Hagåtña, formerly Agana or Agaña, is a coastal village and the capital 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 island's 19 villages in both area and population. However, it remains one of the island's major commercial districts in addition to being the seat of government.
The International Date Line (IDL) is the line between the South and North Poles that is the boundary between one calendar day and the next. It passes through the Pacific Ocean, roughly following the 180.0° line of longitude and deviating to pass around some territories and island groups. Crossing the date line eastbound decreases the date by one day, while crossing the date line westbound increases the date.
The Mariana Islands, also simply the Marianas, are a crescent-shaped archipelago comprising the summits of fifteen longitudinally oriented, mostly dormant volcanic mountains in the northwestern Pacific Ocean, between the 12th and 21st parallels north and along the 145th meridian east. They lie south-southeast of Japan, west-southwest of Hawaii, north of New Guinea, and east of the Philippines, demarcating the Philippine Sea's eastern limit. They are found in the northern part of the western Oceanic sub-region of Micronesia, and are politically divided into two jurisdictions of the United States: the Commonwealth of the Northern Mariana Islands and, at the southern end of the chain, the territory of Guam. The islands were named after the influential Spanish queen Mariana of Austria following their colonization in the 17th century.
In the United States, time is divided into nine standard time zones covering the states, territories and other US possessions, with most of the country observing daylight saving time (DST) for approximately the spring, summer, and fall months. The time zone boundaries and DST observance are regulated by the Department of Transportation, but no single map of those existed until the agency announced intentions to make one in September 2022. Official and highly precise timekeeping services (clocks) are provided by two federal agencies: the National Institute of Standards and Technology (NIST) ; and the United States Naval Observatory (USNO). The clocks run by these services are kept synchronized with each other as well as with those of other international timekeeping organizations.
The Uniform Time Act of 1966, Pub. L.Tooltip Public Law 89–387, 80 Stat. 107, enacted April 13, 1966, was a Law of the United States to "promote the adoption and observance of uniform time within the standard time zones" prescribed by the Standard Time Act of 1918. Its intended effect was to simplify the official pattern of where and when daylight saving time (DST) is applied within the U.S. Prior to this law, each state had its own scheme for when DST would begin and end, and in some cases, which parts of the state should use it.
The Eastern Hemisphere is the half of the planet Earth which is east of the prime meridian and west of the antimeridian. It is also used to refer to Afro-Eurasia and Australia, in contrast with the Western Hemisphere, which includes mainly North and South America. The Eastern Hemisphere may also called the "Oriental Hemisphere", and may in addition be used in a cultural or geopolitical sense as a synonym for "Old World."
The Chamorro people 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, a commonwealth of the US. Today, significant Chamorro populations also exist in several U.S. states, including Hawaii, California, Washington, Texas, Tennessee, Oregon, and Nevada, all of which together are designated as Pacific Islander Americans according to the U.S. Census. According to the 2000 Census, about 64,590 people of Chamorro ancestry live in Guam and another 19,000 live in the Northern Marianas.
Moscow Time is the time zone for the city of Moscow, Russia, and most of western Russia, including Saint Petersburg. It is the second-westernmost of the eleven time zones of Russia. It has been set to UTC+03:00 without DST since 26 October 2014; before that date it had been set to UTC+04:00 year-round on 27 March 2011.
Australia uses three main time zones: Australian Eastern Standard Time, Australian Central Standard Time and Australian Western Standard Time.
Philippine Standard Time, also known as Philippine Time (PHT), is the official name for the time zone used in the Philippines. The country only uses a single time zone, at an offset of UTC+08:00, but has used daylight saving time for brief periods in the 20th century until July 28, 1990.
UTC+00:00 is an identifier for a time offset from UTC of +00:00. This time zone is the basis of Coordinated Universal Time (UTC) and all other time zones are based on it. In ISO 8601, an example of the associated time would be written as 2069-01-01T12:12:34+00:00. It is also known by the following geographical or historical names:
The Samoa Time Zone or Samoa Standard Time (SST) observes standard time by subtracting eleven hours from Coordinated Universal Time (UTC-11:00). The clock time in this zone is based on the mean solar time of the 165th meridian west of the Greenwich Observatory.
Most of the United States observes daylight saving time (DST), the practice of setting the clock forward by one hour when there is longer daylight during the day, so that evenings have more daylight and mornings have less. Exceptions include Arizona, Hawaii, and the territories of American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the United States Virgin Islands. The Uniform Time Act of 1966 established a uniform set of rules for states opting to observe daylight saving time.
Guam The following outline is provided as an overview of and topical guide to Guam:
Alaska is officially covered by two time zones - the Alaska Time Zone and the Hawaii-Aleutian Time Zone. The Hawaii-Aleutian Time Zone is used for the Aleutian Islands west of 169°30′W, and the rest of the state uses the Alaska Time Zone. The entirety of Alaska observes daylight saving time.
Time in Palau is given by Palau Time. Palau does not have an associated daylight saving time.