On its way to comet Borrelly, Deep Space 1 set a record at the time for the longest operating time on a spacecraft engine. (An ion engine similar to DS1's is shown at right.)
Deep Space 1 was dubbed the little spacecraft that could
after completing a comet encounter without the use of a star tracker.
Because of Deep Space 1's technology testing, many future missions that would have been unaffordable or even impossible now are feasible.