The slingshot effect

The slingshot effect is the acceleration of a satellite (probe) into the outer solar system or beyond assisted by the gravitational field of a moon and/or planet. If only a single primary body is involved, the acceleration is a change of direction only. If a moon is involved, the three body interaction may increase the angular momentum and kinetic energy of the probe while decreasing the corresponding quantities for the moon. Since the satellite is very small, the alteration in the moon's orbit is too small to be measured.

The three body interaction is the reverse of moon capture (below).

> More