Meridian Longitude Extra Quality Direct

A meridian is an imaginary vertical line on the Earth's surface that connects the North and South Poles. These lines are used to measure longitude, which indicates how far east or west a location is from a starting point called the Prime Meridian.  Core Concepts  What is longitude? - NOAA's National Ocean Service

2. Definition

Longitude is a geographic coordinate that specifies the east-west position of a point on Earth’s surface. It is measured as an angle ranging from 0° at the Prime Meridian to +180° eastward and −180° westward. meridian longitude

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 Prime Meridian. The Prime Meridian: Point Zero A meridian is an imaginary vertical line on

Conclusion

What Exactly is a Meridian Longitude?

In strictly geographic terms, a meridian longitude is a semi-great circle connecting the North Pole to the South Pole. Every line of longitude is exactly one-half of a great circle—meaning it represents the shortest path between two points on the Earth’s surface, but only if you travel along that specific line. - NOAA's National Ocean Service 2

GMT (Greenwich Mean Time): Time is calculated based on the sun’s position relative to the Prime Meridian.

1. Definition & Core Concept

Longitude is a geographic coordinate that specifies the east‑west position of a point on Earth’s surface. It is measured as an angle from the prime meridian (0° longitude) to the meridian passing through the point, ranging from 0° to 180° east or west.