Elon Musk speaking at a presentation in 2015Stephen Lam / Reuters

Even among tech companies, whose product announcements are geared to be grandiose, Elon Musk's Mars-colonization rollout feels like something new.

In a video shared Tuesday at a space exploration conference in Guadalajara,  Musk outlined his plan: Before this century is out, a small team of humans will open a spacecraft door, step onto red ground and stare at the sun faintly shining through Mars’ hazy atmosphere. A few years later, more people will arrive, but the planet that greets them will look increasingly familiar. Mars will be swaddled in clouds, and the same watery blue that characterizes Earth.

The journey will begin on Launch Pad 39A at Kennedy Space Center, where Apollo 11 lofted humans to another world for the first time. Only now, the patron will not be a global superpower, but SpaceX. Musk unveiled his plans at an annual gathering of the International Astronautical Federation, a group founded during the Cold War.

A self-sustaining, shining city on Mars would need about 1 million people, according to Musk, who envisions launching 1,000 ships to get them there. The goal is to become a multi-planetary species, ensuring humanity could survive an extinction event on Earth. The first flights could leave for Mars by 2022, he claims.

“This is about minimizing existential risk and having a sense of adventure. It’s about ensuring the light of consciousness is not extinguished, which I think is really important. … The probable lifespan of human civilization will be much greater if we are a multi-planetary species,” he said. “But the argument I find most compelling is it would be an incredible adventure. Life needs to be more than solving problems every day. You need to wake up and be inspired.”

The first Martians would be wealthy people, presumably the sort who possess both a pioneering spirit and a knack for construction. Musk hopes to lower the cost of a trip to Mars to roughly the median price of a house in the U.S., about $200,000, he said. The first settlers would build pressurized dome shelters on Mars, to protect them from Mars’s harsh climate and tenuous atmosphere. Larger domes would be built to harbor farms capable of feeding a population of one million. Eventually, SpaceX hopes to ship thousands of people per year to the Red Planet.

They would travel using the newly announced Interplanetary Transport System, which consists of a 40-foot-diameter rocket booster and 55-foot-diameter spaceship, codenamed the BFR and BFS, respectively (yes, those acronyms mean what you think they mean). Initially, Musk referred to his ship as the Mars Colonial Transporter, but earlier this month he said he was ditching that name, because the the rocket will be built to go beyond Mars. On Tuesday, he even invoked Europa, a moon of Jupiter that probably has an enormous ocean under its surface.

In the soaring promo video SpaceX unveiled Tuesday, the rocket lifts off and the ship heads to a “parking orbit” while the booster sails back to Earth, landing straight up on the same launchpad. There, it will pick up a new fuel tank and launch itself again, joining the spaceship in orbit and gassing it up for the trip to Mars. It would repeat this three to five times. Fueling the ship off Earth would dramatically lower costs, Musk said.

The ship resembles a multi-decker space shuttle, but without the iconic delta wings. Instead, once in orbit, it unfurls a pair of wing-like solar panels, like a butterfly emerging from a cocoon. The ship, made from carbon fiber, would accommodate at least 100 passengers and maybe up to 200, Musk said. It is gigantic, and could even have room for on-board eateries: “Pizza joints, you name it,” he said. It would have giant windows in its nose to ensure dazzling views.

“It’s got to be fun and exciting. It can’t feel cramped or boring,” he said. “It will be, like, really fun to go.”

While this all sounds like science fiction, Musk is already working on the engine that could make this happen. A few days ago, he tweeted the first glimpse of the Raptor, a powerful engine that can deliver about 500,000 pounds of thrust. It will use liquid methane for fuel, unlike both the Falcon 9 rockets and the space shuttle main engines. This is a strategic choice: While scientists are still hunting for signatures of methane at Mars, it can certainly be manufactured there, using ice and carbon dioxide from the Martian atmosphere.

The Raptor boosts the ship to a cruising speed of about 63,000 mph. After an interplanetary coast lasting several months, the ship will dive toward Mars, gradually tipping up its nose to skid downward in the same manner the space shuttle used to reenter Earth’s atmosphere. The craft’s heat shield will reach temperatures upward of 3,000 degrees Fahrenheit. A few moments before landing, the vehicle will stand upright, just like SpaceX rockets do now, and unfold three legs to balance itself, finally perching on the ground.

Along with safely delivering colonists, the BFR and its attendant ship would have to deliver 100 tons of payload to Mars, which is 100 times larger than the heaviest thing humans have ever sent to the red planet. Landing may be an even bigger challenge than launching; Curiosity, our biggest Mars rover, weighs 1,982 pounds, and needed a combination of parachutes and an audacious, specially designed sky crane to touch down safely. There is almost no room for error in a landing like this; if one thruster misfires, or something goes wrong with the powered descent, the ship will collapse into the dirt. Mars’s atmosphere isn’t thick enough for parachutes to serve as backup.

Even the journey’s midpoint is treacherous. Earth’s magnetic field deflects the worst of solar and cosmic radiation, and even then, humans visiting low Earth orbit are exposed to ionizing radiation that can damage DNA and cause cancer. Once humans leave Earth’s protective cocoon, they will be exposed to dangerous cosmic rays and solar flares. A colonial transport would also likely have to provide some kind of artificial gravity, or at least good enough exercise equipment that astronauts won’t be bed-bound the minute they land. There will be too much work to do to spend weeks recovering and regaining enough muscle and bone density to walk.

Musk admitted that the funding structure for his grand plan is pretty unclear: “Steal underpants, launch satellites, send cargo and astronauts to ISS, Kickstarter, profit,” he joked.

Tuesday’s announcement was remarkable for the way it fleshed out ideas that Musk has been teasing for years. As far back as 2011, he said he wanted to send people to Mars within 10 to 20 years—10 years would be the “best case,” he said at the time. He envisions SpaceX providing transport, not necessarily driving colonization. In that way, SpaceX could be like the shipping companies that brought people from Europe to America in the 17th century, or the railroad firms that laid track to the West.

“Enough would want to go, and who could afford a trip, that it could happen. Almost anyone, if they have saved up and this was their goal, they could ultimately save enough money and move to Mars,” Musk said. “Mars would have a labor shortage for a long time, so jobs would not be in short supply.”

Before any of this can happen, SpaceX has to surmount plenty of technical hurdles on Earth, let alone interplanetary space. It can’t ship people to the next planet over until it figures out how to stop its rockets from exploding, and then how to safely launch humans into low Earth orbit and bring them home.

And then there are the social challenges. A Mars colony would need much more than shiny domes and potato farms. We would need to develop a system to handle property disputes. We would need a Mars tribunal to handle petty and violent crimes. That means we’d probably need a Mars jail, or at least a fair, ethical way to settle scores. That means we would need an off-planet political system, and it’s not clear what that should look like, or who would get to decide.

Musk has said he favors direct democracy, rather than a U.S.-style representative democracy, because “the potential for corruption is substantially diminished.” But he has mostly been mum on the social, legal and moral issues a Mars colony would raise. Getting there is the focus, for now. On Tuesday, Musk said his goal was “to make Mars seem possible.”

“It’s possible that this dream is real; not just a dream, but something that can be made real,” he said.

After that, the BFR and BFS can go beyond Mars, maybe to worlds like Europa, rich with water, or the many other moons of Jupiter and Saturn. But Mars remains the best place to start an Earth colony for several reasons. It is the planet most like Earth, at least during its deep past, and if Musk’s terraforming dreams come true, in its future. The red planet’s rocky surface will give humans a solid footing on which to plant flags. And it has water, perhaps enough to sustain a small colony. In other words, it’s a good start, just like Musk’s video.

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