| Webster's Online Dictionary |
| Expressions | Domain | Definition | |
| Effective radius of the earth | Aerospace | A fictitious value for the radius of the earth, used in place of the geometrical radius to correct for atmospheric refraction when the index of refraction in the atmosphere changes linearly with height. See modified index of refraction. Under conditions of standard refraction the effective radius of the earth is 8.5 * 106 meters, or four-thirds the geometrical radius. If the effective radius is used in ray tracing diagrams, the rays may be drawn as though they were traveling in straight lines. (references) | |
| Effective radius of the Earth | Geography | The radius of an ideal spherical Earth without atmosphere for which propagation paths are along straight lines, the height and ground distances being the same as for the actual Earth in an atmosphere with a constant vertical gradient of refractivity. Source: European Union. (references) | |
Source: compiled by the editor from various references; see credits. | Top | ||
