Clock that governs a billion lives

It was on September 1, 1947, soon after Independence, that the Indian government adopted a standard time (IST). It is more than a clock that governs the daily lives of over a billion people; its origin and significance are rooted in the country’s history, symbolising unity and scientific progress.

The concept, however, was not new, having been introduced by the British government in 1906 after it felt the need for a single time zone for the entire country.

Before the 19th century, timekeeping in India was a regional affair. Each area followed its own local time, determined by the position of the sun. When it was, say, noon in Kolkata, it could still be morning in Mumbai. The system worked well for local activities, but subsequently, became impractical as the country developed and the influence of British rule expanded. The need for a standardised time became essential.

The British Raj chose the 82.5° East longitude — passing near Mirzapur in Uttar Pradesh — as the central meridian. This decision was crucial for unifying the vast subcontinent under one standard time and taking a step toward modernisation and uniformity.

The first official astronomer of the Madras Observatory, John Goldingham, calculated the longitude of Madras as 5 hours and 30 minutes ahead of the Greenwich Mean Time (GMT). This was the first-ever use of a local standard time that later evolved into IST. Sri Lanka, too, follows it.

The selection of 82.5° East was not random. This longitude also passes through other states, including Madhya Pradesh, Chhattisgarh, Odisha and Andhra Pradesh.

IST also reflects India’s scientific and technological ambitions. At a time when accurate timekeeping was the hallmark of advancement, the adoption of IST marked a significant step toward a modern world. In essence, IST is not just about knowing when to catch a train or start the workday, it also represents a legacy of India’s journey from colonial rule to Independence. Today, IST plays a vital role in various sectors, from transportation to communication, and continues to synchronise daily life across India.

Despite the vast geographical and cultural differences across the country, IST ensures that everyone follows the same clock. It serves as a reminder that time, in its most literal sense, binds the nation.