Gigameter (Gm): A gigameter is equal to one billion (10^9) meters. It is used for long-distance measurements, such as the size of celestial objects or interplanetary distances.
Mile: The mile is a unit of length primarily used in the United States and some other countries. It is equal to 5,280 feet or 1,609.34 meters. The mile is commonly used for measuring longer distances, such as road distances.