COMET NUCLEUS SAMPLE RETURN MISSIONS WITH ELECTRICALLY PROPELLED SPACECRAFT.

A mission to one of te periodic comets with the return of original, unaltered comet nucleus material to Earth has been declared a project of great scientific importance and desirability by several committees in the US and in Europe. Electric propulsion systems provide the propulsive capabilities which make such missions practical. The present study describes a mission with an electrically propelled spacecraft, launched by the Shuttle with the Centaur G' as upper stage. The spacecraft will travel to the close vicinity of a comet, make a number of scientific observations, collect several drill core samples from the nucleus, and return those samples to Earth. An almost ideal mission opportunity with a rendezvous early in 1997 will be offered by comet P/Wild 2.