Elon Musk, the CEO of SpaceX, unveiled his company's plans for sending humans to explore and colonize Mars at a Sept. 27 conference in Mexico. Musk's aspirations for the Red Planet have been widely known for years, and the inventor famously quipped, "I'd like to die on Mars, just not on impact." Now Musk is taking steps to see that goal through: According to his plan, SpaceX will use a powerful new rocket system, the Interplanetary Transport System (ITS), to reach Mars by roughly 2022.
First, SpaceX would launch an empty Mars vehicle into Earth's orbit, refueling and stocking it with supplies over the span of multiple launches between the ground and the orbiting rocket. Once fully supplied, the ITS would start its engines and chart a course for Mars. It would, however, have to wait for the optimal conditions before embarking on its journey. Mars and Earth move closest to each other once every 26 months or so; at that distance, the rocket could reach the Red Planet in 80-160 days. After landing on the planet, the Mars vehicle's crew would establish a colony that would produce, among other things, more propellant. This would enable the ITS to travel back to Earth for reuse.
As envisioned, the ITS will boast 550 metric tons of low-earth orbit (LEO) capacity, outpacing even the Saturn V — at an LEO capacity of 140 metric tons, the largest rocket ever launched. By comparison, SpaceX's latest Falcon 9 rocket model has only 22.8 metric tons, though the Falcon Heavy rocket set to debut next year is estimated to have 54.4 metric tons.
Musk's ambitious plan will be both expensive and difficult. During the conference, he acknowledged that even the most conservative estimate puts the price of a Mars mission at $10 billion per person — a prohibitive cost, considering at least 100 people could travel in each ITS. That estimate also disregards four key features of the scheme: the ability to reuse the ITS, boosters and refueling tanks; to refuel in orbit; to produce propellant on Mars; and to use an optimal propellant like supercooled methane. Collectively, Musk believes these four features could push costs as low as $200,000 per person.
Finding the funds for the Mars mission is perhaps the most daunting challenge facing Musk at this point, though it is by no means the only one. Scaling up the project will require massive resources, and at present, SpaceX has only its own profits and financing platforms like Kickstarter to rely on. Moreover, SpaceX does not appear to have a plan in place for selecting potential participants or designing a space colony. An extensive amount of research must still be done to make the program a success. For now, SpaceX will continue to develop parts of the systems in its plans. After a few years, it will try to send at least one object to Mars during each of the launch windows that open. This timeline is admittedly aggressive, but the company did have its first successful test of the Raptor Engine designed to power the ITS earlier this month. (The ITS' first stage will use 42 of the engines.)
Of course, SpaceX is not the only company seeking to boldly go where no one has gone before. In September, Boeing announced its own project to send humans to Mars. Its space station, which would be built over a four-year period beginning in 2021, is intended to serve as a stepping-stone or proving ground for the technologies needed to travel to and operate on Mars.
But colonizing the red planet, as Musk aims to do, is different than simply visiting it. If he is successful, it could have wide-reaching geopolitical implications. Resource scarcity here on Earth will eventually force mankind to look elsewhere for those resources — whether on asteroids, Mars or farther afield — to meet demand. As countries increase their presence in space, the competition to control it will heat up. And though on its face Musk's plan is that of a private company, the United States depends on public-private partnerships with firms like SpaceX to advance its security interests in Earth's orbit and beyond.