A question for you more astronomically-minded. As an intermediate step between the Moon and Mars, what about a mission to a near Earth asteroid? Using the CEV and a modified lander (for use as a Hab and for some of the propulsion). Perhaps the astronauts could land on the asteroid using a MMU-type backpack, while the spacecrat orbited. The lander then, would not carry any landing gear, saving the weight for other uses. Are there any candidates that would be worthwhile during the 2018-25 time frame? I'm not sure it would be worth doing, I'm just enjoying thinking out-of-the-box.