pitkittäiskoordinaatiston

Pitkittäiskoordinaatisto, known in English as longitudinal coordinate system, is a system used to define the position of a point on the surface of the Earth or another celestial body based on its angular distance east or west of a prime meridian. This system is a fundamental component of geographic coordinate systems, working in conjunction with latitude.

The prime meridian, typically the one passing through Greenwich, London, is designated as having a longitude of 0 degrees. Longitudes are measured in degrees, minutes, and seconds, or in decimal degrees, from this prime meridian. Positions to the east of the prime meridian are given positive values, ranging from 0 to 180 degrees East, while positions to the west are given negative values, or are denoted as West, also ranging from 0 to 180 degrees. The 180th meridian, both East and West, is often referred to as the International Date Line.

Understanding longitude is crucial for navigation, cartography, and many scientific disciplines. It allows for precise location determination, facilitates the creation of maps, and is essential for understanding time zones, as the Earth rotates and different longitudes experience sunrise and sunset at different times. The concept of longitude has been developed and refined over centuries, with significant contributions from astronomers and geographers.