Characteristics of a dual mission concept for intensive study of moon and Mars or moon and asteroids

An assessment is presented of the results of recent feasibility studies on a low cost dual mission concept, employing a single spacecraft for the sequential, intensive survey of two planets. After establishing the features of a basic lunar-Martian polar orbiting mission in the context of existing spacecraft and propulsion technology, an examination of trajectory options shows that an earth return maneuver allows the application of the same concept to lunar-asteroid missions and offers substantial savings for the lunar-Martian mission. The implications of Centaur availability for extension of this concept to main-belt asteroids and to tripple missions are considered, along with questions of cost and reliability.