Meridian Longitude [updated] Jun 2026

Longitude and time are inextricably linked. Because the Earth rotates 360 degrees in 24 hours, it turns 15 degrees every hour. Therefore, every degree of longitude represents a four-minute time difference from its neighbor.

In 1884, the International Meridian Conference met in Washington, D.C., and established the (passing through the Royal Observatory in Greenwich, London) as the world's official Prime Meridian. It is designated as 0° longitude . How Longitude is Measured Longitude is measured in degrees, minutes, and seconds: meridian longitude

The physical distance between longitude lines is widest at the Equator (about 111 kilometers or 69 miles per degree) and shrinks to zero at the poles. Longitude and time are inextricably linked

However, in 1884, an international conference decided to establish a single, universal meridian to facilitate global navigation and timekeeping, settling on Greenwich, England, due to its historical role in ocean navigation [UH Manoa]. Key Differences: Longitude vs. Latitude In 1884, the International Meridian Conference met in

Unlike lines of latitude (which are parallel), all meridians converge at the poles. They are not parallel, making them unique in grid systems. The Prime Meridian: By international convention, the 0∘0 raised to the composed with power

当我们再次仰望星空或查看手机上的位置共享时，不禁感叹：正是通过这条看不见的经线之网，一个属于全人类的坐标系，在一代又一代人的不懈追问下，从模糊变成了清晰。