# Escape Velocity

## Description

Escape velocity is the speed at which the kinetic energy plus the gravitational potential energy of an object is zero. It is the speed needed to “break free” from a gravitational field without further propulsion. For a spherically symmetric massive body, the escape velocity at a given distance can be calculated by the mass of the massive body, and the distance from the center of gravity. ( Atmospheric friction (air drag) is not taken into account).

“Escape velocity” is the initial speed required to go from an initial point in a gravitational potential field to infinity with a residual velocity of zero, with all speeds and velocities measured with respect to the field.

## Variables

U_{e} | Escape Velocity (m/s) |

G | Newtonian constant of gravitation |

M | Mass of the massive body (kg) |

r | Distance from center of gravity (m) |