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ScienceTechnologyLaw

Standard time and the prime meridian

The world agrees to divide the day into zones measured from Greenwich.

When
Known to
± 1 year
Era
Industrial, Holocene

The International Meridian Conference in Washington in 1884 adopts Greenwich as the prime meridian and establishes the framework of time zones, driven by railways and telegraphy which had made local solar time unworkable. France abstained and used Paris mean time for decades. Every timestamp in modern life descends from this agreement, and it is the moment global coordination becomes a technical necessity rather than an aspiration.

Just before

Just after