Elon Musk is serious about colonizing Mars. An article in the journal New Space summarizes Musk's plans on how a human colonization of Mars can actually happen.
Making Humans A Multi-Planetary Species
Musk has never been shy about his space travel ambitions for the humankind, but as it turns out, he has actually already mapped out a pretty clear plan on how the human race could eventually colonize the planet Mars. Apart from avoiding the impending doom of human extinction, Musk's idea is to turn the human race into a space-bearing, multi-planetary species.
In the New Space article, Musk's plan to turn the Red Planet into self-sustaining planet instead of a mere outpost is summarized based on the speech he gave at the 67th International Astronautical Congress in Mexico.
There are quite a few planets in our own solar system, and more exoplanets close to home are being discovered every day. So why Mars? Well, Musk makes his case by pointing out the difficulties of trying to colonize any of the other planets. Simply put, Venus is much too hot and acidic, Mercury is much too close to the sun, while Jupiter and Saturn are both much too far from it.
Musk also described the possibility of colonizing the moon but makes his case that it is much too small, has no atmosphere, and not quite as rich in resources as Mars.
Mars, on the other hand, has 37 percent of the earth's gravity, is near enough to the sun to have decent sunlight, and has an atmosphere.
Improving Trip Costs
One obvious obstacle to colonizing Mars is the sheer steepness of the price of one ticket, which Musk estimates to be about $10 billion per person. To lower the high costs, Musk believes that there are certain things that must be addressed for such a mission, namely using an aircraft with full reusability and capability to refill in orbit and being able to produce the right kind of propellant in Mars, which, according to Musk, is methane.
The Right Vehicle
Musk estimates that if a million people are needed to create a self-sustaining city on Mars and an Earth-to-Mars trip can only be done once every two years, it would be wise to maximize the cargo of the space ship as much as possible.
For this mission, Musk believes that massive improvements of current space vehicles are needed. Though even he confesses that a project of this scale would be difficult to fund, he expects that these improvements could ultimately drop the current Mars trip cost to as low as $100,000 for a Mars trip.
If things go according to plan, though he admits that there are a lot of risks involved in this mission, Musk expects that the Mars colonization could begin within a 10-year time frame.