Longitude refers to the angular distance of a place east or west of the meridian at Greenwich, England, or west of the standard meridian of a celestial object. It is usually measured in degrees (°), minutes ('), and seconds ("). Longitude is an essential component of every geographic coordinate system which is used to accurately pinpoint locations on Earth.

What is Longitude?

Longitude forms part of the basis for cartography and navigation. Lines of longitude, also known as meridians, run from the North Pole to the South Pole. When paired with its counterpart, latitude, longitude enables precise location setting and correlation around the globe. The Prime Meridian, which is designated 0° longitude, passes through the Royal Observatory in Greenwich, England. This serves as the reference point for all other lines of longitude, which extend up to 180° eastward and -180° westward.

Longitude has crucial applications in various sectors, from enabling GPS navigation to assisting in international law, which delineates boundaries in longitudes and latitudes. Understanding longitude is vital for several activities, such as ocean and flight navigation, mapping and surveying, and even orchestrating international telecommunications.


What is the Prime Meridian?

The Prime Meridian is the line of 0° longitude, the starting point for measuring distance both east and west around the Earth. The Prime Meridian passes through Greenwich, London, UK.

How does Longitude affect time zones?

Time zones are defined by lines of longitude. Each time zone is approximately 15° of longitude wide and represents one hour, with the Prime Meridian representing Greenwich Mean Time (GMT).

What is the difference between Longitude and Latitude?

Longitude lines run from North to South, while Latitude lines run from East to West. The point where they intersect determines a specific location on the globe. Longitude represents locations East or West of the Prime Meridian, while Latitude represents locations North or South of the equator.

Why is Longitude important?

Longitude plays a crucial role in navigation and cartography, as it allows exact locations to be identified anywhere on Earth. It’s also integral to defining time zones and international borders.

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