Indian Standard Time (IST) is the time observed throughout India and Sri Lanka, with a time offset of UTC+05:30. India does not observe daylight saving time (DST) or other seasonal adjustments, although DST was used briefly during the Sino–Indian War of 1962 and the Indo–Pakistani Wars of 1965 and 1971. In military and aviation time, IST is designated E* ("Echo-Star").
Indian Standard Time is calculated on the basis of 82.5° E longitude, which is...
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Indian Standard Time (IST) is the time observed throughout India and Sri Lanka, with a time offset of UTC+05:30. India does not observe daylight saving time (DST) or other seasonal adjustments, although DST was used briefly during the Sino–Indian War of 1962 and the Indo–Pakistani Wars of 1965 and 1971. In military and aviation time, IST is designated E* ("Echo-Star").
Indian Standard Time is calculated on the basis of 82.5° E longitude, which is just west of the town of Mirzapur, near Allahabad in the state of Uttar Pradesh.
One of the earliest descriptions of standard time in India appeared in the 4th century CE astronomical treatise Surya Siddhanta. Postulating a spherical earth, the book defined the prime meridian, or zero longitude, as passing through Avanti, the ancient name for the historic city of Ujjain (23°10′58″N 75°46′38″E / 23.18278°N 75.77722°E / 23.18278; 75.77722 (Avanti (Ujjain))), and Rohitaka, the ancient name for Rohtak (28°54′N 76°38′E / 28.9°N 76.633°E /...
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