# Geocentric radius of the Earth

## Description

Geodetic latitude is the angle between the normal and the equatorial plane. The distance from the Earth’s center to a point on the spheroid surface at a defined geodetic latitude is the Geocentric radius of the Earth.

Related formulas## Variables

R_ϕ | Geocentric radius of the Earth (km) |

a | The equatorial radius of the Earth (km) |

ϕ | The geodetic latitude (degree) |

b | The polar radius of the Earth (km) |