|
|
|
|
|
|
The parsec (symbol: pc) is a unit of length used to measure large distances to astronomical objects outside the Solar System.
A league is a unit of length (or, in various regions, area). It was common in Europe and Latin America, but is no longer an official unit in any nation. The word originally meant the distance a person could walk in an hour. Since the Middle Ages, many values have been specified in several countries.