Rethinking Hillhouse

Jim says, "it would take 2-3 SLS B-II launches at a minimum for a crewed mission  [to mars]."

I really don't want to wait 20 years. Is there a better way?

The assumption seems to be either we build battlestar galactica in orbit to send to mars or we use Orion. I say forget both, we send twelve crew in two Sundancers.

Why twelve? Because that divides evenly into 3 Mars One landers which they've already discussed with SpaceX to cost $190m each and will be available in just a few years (January 2016?) Each will land 2.5mt; 4 crew and the remaining mass in supplies. So we preposition these in mars orbit with about 6mt of supplies for $570m.

We give the Falcon Heavy whatever upper stage it needs to send the Sundancers to mars orbit. The Sundancers, while less mass than Orion, are about twice the mass of Dragon which the FH would be able to send to mars. Thus a more powerful upper stage would probably be required to send the Sundancers. Perhaps the Centaur? Update: Another option is to use 3 FH for the landers and 2 SLS for the Sundancers.

The Sundancers would have ion thrusters for mid course correction and mars capture. With 2 Sundancers and 3 landers (5 FH launches) the total cost of this mission is right around one billion dollars and could be done in 5 to 10 years depending on how much focus we put on it.

We should of course send some landers to the surface of mars first but that's true regardless of the rest of the mission.

So one billion in ten years or three billion in twenty years.  Hmmmm... now that's a difficult decision!?

Update: As Peter Wilson says,

Simply put, the SLS program should be canceled now to free up approximately $10 billion programmed for this decade. This money could then be redirected to continue the planned flight tests of the Orion Sundancer spacecraft with the much lower-cost Falcon Heavy booster while making a robust investment in a first-generation space station in the vicinity of the Moon. An investment in such a cislunar station would provide—by the early 2020s—a multifunctional platform to act as a fuel depot, a workstation for robotic operations on the Moon and a habitat to protect against the more intense radiation environment outside of the Earth's magnetic field. This station could even be used as a habitat during longer-duration human missions to an asteroid and eventually to Mars.

Sounds about right (w/ my one correction.)

Update: Returning from mars (assuming that some we send are not planning to be permanent colonists.) The Sundancers now in orbit could return to earth on a slow trajectory, but how do those on the surface get to them? Refueling the landers probably doesn't do it. SuperDracos may take you to a certain altitude but not all the way to mars orbit. You need about 4 km/s and they only provide a few hundred m/s. I haven't a clue really. Zubrin's semi direct plan comes closest with a Mars Ascent Vehicle (MAV) where the Sundancers could take the role of the orbital ERV in that plan. You would simply plug in the cost for the MAV which would be now be much more than the original one billion estimate.

Adding a return simply pushes mars farther into the future. We should not wait.

Update: Dragon is a very low mass vehicle for seven. What about the MCT? Musk isn't telling, but does say it will be roomy. Do you suppose it will include Bigelow technology? You can't fool the rocket equation.