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:

Coordinates are marked as E (East) or W (West). For example, New York City sits at approximately 74° W, while Tokyo is at roughly 139° E. The Connection Between Longitude and Time

We apply similar coordinate systems to map the surfaces of Mars and the Moon.

Meridian Longitude: The Invisible Lines That Define Our World

This relationship is why time zones were created. Every 15° increment away from the Prime Meridian generally represents a one-hour difference from . If you travel 15° East, you are effectively "stepping" one hour into the future. Why It Matters Today

When we talk about "meridian longitude," we are referring to the angular distance of a place east or west of a specific reference line known as the . The Prime Meridian: Point Zero

Longitude isn’t just about distance; it’s the foundation of how we measure time. Because the Earth rotates 360° every 24 hours, it moves .

Meridian Longitude -

Coordinates are marked as E (East) or W (West). For example, New York City sits at approximately 74° W, while Tokyo is at roughly 139° E. The Connection Between Longitude and Time meridian longitude

We apply similar coordinate systems to map the surfaces of Mars and the Moon. In 1884, the International Meridian Conference met in

Meridian Longitude: The Invisible Lines That Define Our World For example, New York City sits at approximately

When we talk about "meridian longitude," we are referring to the angular distance of a place east or west of a specific reference line known as the . The Prime Meridian: Point Zero

Longitude isn’t just about distance; it’s the foundation of how we measure time. Because the Earth rotates 360° every 24 hours, it moves .