Millions of people needed for Mars colony, so 80k+ would just be the number moving to Mars per year news.yahoo.com/huge-mars-colo…
— Elon Musk (@elonmusk) November 27, 2012
Reusable rockets are the difference between something costing half a percent of GDP and all of GDP.
At a joint press conference with NASA , SpaceX CEO Elon Musk said the company will try a water landing of its Falcon 9 first stage later year (2013). The landing will be the start of a series of flight tests that could culminate with an attempted propulsive landing of a first stage back at its launch site in the middle of 2014, Musk said. A successful propulsive landing would enable reusable rockets which could lower the cost of launching to space by 100 times.
The cost of the propellant is only about 0.3 percent of the cost of rocket. And we have a low cost rocket….The Falcon 9 is 60 million dollars, and that’s for something with four times the thrust of a 747 and about the same liftoff mass. So that’s a good deal. But the propellant is only 200,000 dollars. So if we could use the — hypothetically use — Falcon 9 rocket 1,000 times, then the capital cost would go from being 60 million dollars per flight to 60,000 dollars a flight.