Megameter to Kilometer Converter

A megameter (Mm) is a unit of length in the metric system equal to one million meters (10⁶ m). It is commonly used to measure very large distances, particularly in astronomy and geography.

The megameter was introduced as part of the metric system's decimal-based approach to measurement. The prefix 'mega-' comes from the Greek word 'megas' meaning 'great' or 'large', and was officially adopted in 1960 as part of the International System of Units (SI).

Megameters are primarily used in scientific contexts, particularly in astronomy for measuring distances between celestial bodies within our solar system, and in geography for measuring very large terrestrial distances such as the diameter of planets or the distance between continents.

A kilometer (km) is a unit of length in the metric system equal to 1,000 meters. It is one of the most commonly used units for measuring medium to long distances on Earth.

The kilometer was first introduced in 1795 during the French Revolution as part of the original metric system. The term comes from the Greek word 'khilioi' meaning 'thousand' and the French word 'mètre'. It became widely adopted throughout Europe in the 19th century and is now the standard unit for road distances in most countries worldwide.

Kilometers are extensively used for measuring road distances, city planning, geographical surveys, and athletic events like marathons. Most countries use kilometers for speed limits (km/h) and fuel efficiency measurements. It's the standard unit for mapping and GPS navigation systems globally.