A mile is a unit of distance commonly used in the United States and a few other countries. It is part of the imperial system of measurement, which also includes units like feet and inches. One mile equals 1,609.34 meters or about 1.609 kilometers. This is quite different from the metric system, which is based on units of ten and is used by most countries around the world and scientific organizations, including NASA.
NASA primarily uses the metric system for its measurements and calculations, although it sometimes uses miles for communication with the public. The metric system is favored in science and engineering because of its simplicity and ease of conversion between units.
In everyday situations, a mile is often used to measure distances on land, especially in countries like the U.S. where it is the standard unit for road signs and speed limits. For someone used to the metric system, this can be confusing since the metric system is much more straightforward. Transitioning entirely to the metric system in the U.S. has been a long-debated topic, but for now, both systems coexist in different contexts.