|Indian Standard Time|
Indian Standard Time
|17:09, 30 September 2020 IST|
|Observance of DST|
|DST is not observed in this time zone.|
Indian Standard time (IST) is the time zone observed throughout India, with a time offset of UTC+05:30. India does not observe daylight saving time or other seasonal adjustments. In military and aviation time IST is designated E* ("Echo-Star").
Indian Standard Time is calculated on the basis of 82.5°E longitude in the city of Mirzapur, Uttar Pradesh, which is situated approximately on the corresponding longitude reference line.
After Independence in 1947, the Union government established IST as the official time for the whole country, although Kolkata and Mumbai retained their own local time (known as Calcutta Time and Bombay Time) until 1948 and 1955, respectively. [ citation needed ]The Central observatory was moved from Chennai to a location at Shankargarh Fort in Prayagraj district, so that it would be as close to UTC+05:30 as possible.
Daylight Saving Time (DST) was used briefly during the China–India War of 1962 and the Indo-Pakistani Wars of 1962 and 1971.
The country's east–west distance of more than 2,933 kilometres (1,822 mi) covers over 29 degrees of longitude, resulting in the sun rising and setting almost two hours earlier on India's eastern border than in the Rann of Kutch in the far west. Inhabitants of the northeastern states have to advance their clocks with the early sunrise and avoid the extra consumption of energy after daylight hours.
In the late 1980s, a team of researchers proposed separating the country into two or three time zones to conserve energy. The binary system that they suggested involved a return to British-era time zones; the recommendations were not adopted.
In 2001, the government established a four-member committee under the Ministry of Science and Technology to examine the need for multiple time zones and daylight saving.The findings of the committee, which were presented to Parliament in 2004 by the Minister for Science and Technology, Kapil Sibal, did not recommend changes to the unified system, stating that "the prime meridian was chosen with reference to a central station, and that the expanse of the Indian State was not large."
Though the government has consistently refused to split the country into multiple time zones, provisions in labour laws such as the Plantations Labour Act, 1951 allow the Union and State governments to define and set the local time for a particular industrial area.In Assam, tea gardens follow a separate time zone, known as the Chaibagaan or Bagan time ('Tea Garden Time'), which is one hour ahead of IST. Still Indian Standard Time remains the only officially used time.
In 2014, Chief Minister of Assam Tarun Gogoi started campaigning for another time zone for Assam and other northeastern states of India.However, the proposal would need to be cleared by the Union Government.
In June 2017, Department of Science and Technology (DST) indicated that they are once again studying feasibility of two time zones for India. Proposals for creating an additional Eastern India Time (EIT at UTC+06:00), shifting default IST to UTC+05:00 and Daylight saving (Indian Daylight Time for IST and Eastern India Daylight Time for EIT) starting on 14 April (Ambedkar Jayanti) and ending on 2 October (Gandhi Jayanti) was submitted to DST for consideration. [ needs update ]
Official time signals are generated by the Time and Frequency Standards Laboratory at the National Physical Laboratory in New Delhi, for both commercial and official use. The signals are based on atomic clocks and are synchronised with the worldwide system of clocks that support the Coordinated Universal Time.
Features of the Time and Frequency Standards Laboratory include:
IST is taken as the standard time as it passes through almost the centre of India. To communicate the exact time to the people, the exact time is broadcast over the national All India Radio and Doordarshan television network. Telephone companies have dedicated phone numbers connected to mirror time servers that also relay the precise time. Another increasingly popular means of obtaining the time is through Global Positioning System (GPS) receivers.
A time zone is a region of the globe that observes a uniform standard time for legal, commercial and social purposes. Time zones tend to follow the boundaries of countries and their subdivisions instead of strictly following longitude because it is convenient for areas in close commercial or other communication to keep the same time.
Daylight saving time (DST), also daylight savings time or daylight time and summer time, is the practice of advancing clocks during warmer months so that darkness falls later each day according to the clock. The typical implementation of DST is to set clocks forward by one hour in the spring and set clocks back by one hour in autumn to return to standard time. In other words, there is one 23-hour day in late winter or early spring and one 25-hour day in the autumn.
Western European Summer Time is a summer daylight saving time scheme, 1 hour ahead of Greenwich Mean Time and Coordinated Universal Time. It is used in:
Japan Standard Time, abbreviated as JST, is the standard time zone in Japan, 9 hours ahead of GMT. There is no daylight saving time, though its introduction has been debated several times. During World War II, it was often called Tokyo Standard Time.
The Hawaii–Aleutian Time Zone observes Hawaii–Aleutian Standard Time (HST), by subtracting ten hours from Coordinated Universal Time (UTC−10:00). The clock time in this zone is based on the mean solar time of the 150th meridian west of the Greenwich Observatory.
Time in the United States, by law, is divided into nine standard time zones covering the states, territories and other US possessions, with most of the United States 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. 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.
Time in New Zealand is divided by law into two standard time zones. The main islands use New Zealand Standard Time (NZST), 12 hours in advance of Coordinated Universal Time (UTC) / military M (Mike), while the outlying Chatham Islands use Chatham Standard Time (CHAST), 12 hours 45 minutes in advance of UTC / military M^ (Mike-Three).
The Atlantic Time Zone is a geographical region that keeps standard time—called Atlantic Standard Time (AST)—by subtracting four hours from Coordinated Universal Time (UTC), resulting in UTC−04:00. During part of the year, some portions of the zone observe daylight saving time, referred to as Atlantic Daylight Time (ADT), by moving their clocks forward one hour to result in UTC−03:00. The clock time in this zone is based on the mean solar time of the 60th meridian west of the Greenwich Observatory.
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 Western Standard Time, Australian Central Standard Time, and Australian Eastern Standard Time. Time is regulated by the individual state governments, some of which observe daylight saving time (DST). Australia's external territories observe different time zones.
There are eleven time zones in Russia, which currently observe times ranging from UTC+02:00 to UTC+12:00. Daylight saving time is not used in Russia. From 27 March 2011 to 26 October 2014, permanent DST was used.
Sri Lanka Standard Time (SLST) is the time zone for Sri Lanka. It is 5 hours and 30 minutes ahead of GMT/UTC (UTC+05:30).
Bangladesh Standard Time (BST) is the time zone of Bangladesh. It is offset six hours ahead of Coordinated Universal Time, and observed as a national standard throughout the country. Bangladesh briefly observed daylight saving time (DST) in 2009 to cope with the ongoing electricity crisis, but in 2010 the decision was cancelled by the government of Bangladesh.
The Republic of India uses only one time zone across the whole nation and all its territorries, called Indian Standard Time (IST), which equates to UTC+05:30, i.e. five and a half hours ahead of Coordinated Universal Time (UTC). India presently does not observe daylight saving time.
Daylight saving time in the United States is the practice of setting the clock forward by one hour during the warmer part of the year, so that evenings have more daylight and mornings have less. Most areas of the United States and Canada observe daylight saving time (DST), the exceptions being Arizona, Hawaii, and the overseas territories of American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the United States Virgin Islands. The Uniform Time Act of 1966 established the system of uniform daylight saving time throughout the US.
National Standard Time is the official time zone in Taiwan defined by an UTC offset of +08:00. This standard is also known as Taiwan Time (臺灣時間), Taipei Time (臺北時間) and historically as Chungyuan Standard Time (中原標準時間) until the early 2000s.
Ireland uses Irish Standard Time in the summer months and Greenwich Mean Time in the winter period..
Daylight saving time in the Americas is the arrangement in the Americas by which clocks are advanced by one hour in spring and moved back in autumn, to make the most of seasonal daylight. The practice is widespread in North America, with most of Canada, Mexico, and the United States of America participating, but much less so in South America.
As of 2017, daylight saving time is used in the following Asian countries:
The only African countries and regions that use daylight saving time are: