The National Physical Laboratory (NPL)—India's official timekeeper—has suggested that India should have two time zones, with the Northeastern states on 'IST-II', running an hour ahead of the rest of the country, Down To Earthreported. This has been a long-running demand in the region, where sunset and sunrise are well ahead of 'office timings', which are according to India Standard Time (IST).
The Gauhati High Court had, in 2017, quashed a plea seeking a separate time zone for the northeast. The court had noted that a high-level committee, constituted by the Ministry of Science & Technology, had recommended continuation of the present system of a single and uniform standard time throughout the country, and had recommended that the work timings for the northeastern states be moved up by one hour.
However, the NPL report suggested that it is technically feasible to have two time zones, although this is just a recommendation and the ministry will choose whether or not to take it up.
"The demarcation line will pass through the border of West Bengal and Assam and will be very narrow. Only two railway stations—New Cooch Behar and Alipurduar—will need to be managed for time adjustment. Since the signalling system is not fully automatic, two time zones will not cause any disruption in railway operations," NPL director D K Aswal told India Science Wire.
"This is the scientific proof we have provided, now the political decision rests with the government. It is up to the ministry to decide whether or not to implement it," Aswal told Hindustan Times.
To implement and generate IST-II, NPL will have to establish a Primary Time Scale (PTS), which is an ensemble of five caesium clocks and one hydrogen maser, in one of the north-eastern states, similar to the PTS for IST-I, which is located in Delhi. A caesium clock measures time on the basis of the resonance (or change of energy state of an isotope of caesium) and a hydrogen maser measures time on the basis of the resonance of hydrogen across energy states.