|
|
|
|
|
|
Earth radius is the distance from Earth's center to its surface, about 6,371 km (3,959 mi). This length is also used as a unit of distance, especially in astronomy and geology, where it is usually denoted by R⊕.
Petameter or petametre is equal to 1015 meters (unit of length), comes from a combination of the metric prefix peta (P) and the SI unit of length meter (m). Plural name is petameters.