That's interesting you should mention this, as the dynamics of an Earth-sized planet with a Moon-sized Moon interacting with, say, a Jovian-sized planet with an Earth-sized moon could very well wind up with the Earth-sized planet forfeiting it's own moon and walking away with Jovian's moon.

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If I set the budget, we'd have Ares and more. Unfortunately, I don't set the budget, and Ares is just too expensive and too far out for us to accomplish our goals within the budget we were given.

If we halt the ISS, all versions of Ares, and transport Orion and Altair aboard DIRECTv3's Jupiter family of Shuttle-Derived Launch Vehicles, we just might make it back to the Moon by 2020.