But how does one transport so many people, and related cargo, across space? Given that the minimum distance between Earth and Mars is 55 million km, a trip is possible only about once every 26 months. Getting there in numbers involves improving the efficiency of spaceflight. Mr Musk reckons that if costs drop to $200,000 per individual — same as the median cost of buying a house in the United States — travel could be a practical option.
His solution is to design methane-propelled spaceships, which can be re-used and are capable of ferrying 100 to 200 passengers each trip. Alongside, build orbital refuelling stations as well as tankers to store fuel. Initial trips will last 80-odd days but this time frame can gradually be reduced to 30 days. Space ships will launch with minimal fuel to get out of Earth’s gravity and tank up at the orbital stations. Mr Musk also provides a lot of details on ship specifications and designs. Such futuristic vehicles could transport cargo from New York to Tokyo in about 10 minutes.
Of course, not everything has been sorted out. For instance, it is not clear how the settlers will be protected from the very high, possibly lethal, radiation in space. The plan also glosses over how settlers will live on the red planet. Mars can be very cold with night temperatures of minus 120 degrees Celsius. It has little atmosphere, no water and no magnetic field to speak of. Mr Musk does suggest “terraforming” to make Mars more Earth-like by pressurising the atmosphere to grow plants and heating the planet to liquefy ice, thickening the atmosphere and raising the oxygen content. But Mars’ lack of a magnetic field might mean that atmosphere will leak away, even assuming the planet can be heated.
NASA released its own plans for going to Mars a couple of years ago. While it hopes to undertake manned missions by 2030, the US space agency is not looking at settlements. China, too, is planning experiments to grow plants on the moon. But in terms of the scale of ambition, SpaceX goes many steps further. In fact, Mr Musk says he hopes to die on Mars (and not from a spaceship crash).
The plans may be too ambitious and some of the problems insurmountable. But if SpaceX, or some competitor, delivers reusable rockets, radiation shielding, cheap methane production and orbital refuelling, it will have pushed space exploration into a new era and altered the logistics of cargo transportation irrevocably. R&D of this nature can have unpredictable but positive consequences, giving rise to discoveries across multiple domains.