What type of geographic coordinate measures an object's east-west position on the Earth's surface?

Longitude is the geographic coordinate that measures an object's east-west position on the Earth's surface. It is expressed in degrees, indicating how far a location is from the Prime Meridian, which is located at 0 degrees longitude. Locations to the east of the Prime Meridian have positive longitude values, while those to the west have negative values. This system allows for precise navigation and mapping, making it essential for understanding geographical positioning.

In contrast, latitude measures an object's north-south position, elevation refers to the height above a reference point (often sea level), and altitude typically describes vertical distance relative to the earth’s surface or a specific location within a three-dimensional context. This highlights the unique role of longitude in defining east-west orientation.