The Indicators are based upon atomic clocks and synchronised with the worldwide program of clocks that assist Coordinated Universal Time. India's time zone relies to the eighty two.5°E meridian, which passes through Mirzapur. The 50 %-hour offset was chosen to maintain the time close to the mean photo voltaic time https://india-standard-time46320.wikiitemization.com/5986835/little_known_facts_about_ist_time