Name
- Radius
Description
- Radius is a kind of length. [1]
- A radius of a circle or sphere is any line segment from its center to its perimeter. [2]
Radius in astronomy
- Because planets and stars are not perfectly spherical, the radius is the average distance from an astronomical object's center to its surface.
- The Earth radius, Jupiter radius, solar radius and the kilometer (km), are the units used the most often to measure the radius.