13 October - The Greenwich Meridian (0 degrees longitude) became the reference point for measuring time and longitude globally

 

The International Meridian Conference, which took place from October 1 to October 22, 1884, in Washington, D.C., established the Prime Meridian at the Greenwich Observatory in London, UK. This decision was a crucial step in the standardization of time and the establishment of time zones around the world. The Greenwich Meridian (0 degrees longitude) became the reference point for measuring time and longitude globally, and it is still the prime meridian used today. This conference also led to the adoption of the Universal Day system and the division of the world into 24 time zones, each one hour apart.