SpaceX successfully tested its Raptor interplanetary drive prototype this week, but that was only a hint of what SpaceX has planned. On Tuesday, founder Elon Musk took the stage at the International Astronautical Congress (IAC) to explain how SpaceX plans to make humanity a multi-planetary species. There are still some unanswered questions. But by focusing on fuel efficiency and reusable rocket design, Musk says he believes almost anyone will be able to go to the Red Planet and build a new society.
Before he got into talking about the Interplanetary Transport System, Musk explained why Mars would be the ideal target for human colonization efforts instead of the moon, for instance. While Mars is smaller than the Earth, it still has enough gravity for people to live and work in a similar way to how they do on Earth. The mineral wealth on Mars is also greater than what you’d find on the moon. In addition, Mars has an atmosphere, although it’s very thin.
By increasing the temperature of Mars, Musk says the atmosphere could be thickened and enriched with oxygen. We already know there’s plenty of frozen water on Mars, so increasing the temperature could result in liquid oceans. The carbon dioxide atmosphere Mars currently has could easily be compressed to grow plant life as well. Taken together, that makes Mars feasible for a self-sufficient human colony.
The technology technically exists to go to Mars because it is fairly close in astronomical terms. But it’s extremely expensive. A scaled up Apollo-style mission would cost about $10 billion per person transported. SpaceX plans to develop a fleet of reusable vehicles and can be refueled in orbit. With the right systems in place. SpaceX believes it can get the cost of a ticket to Mars down to $200,000, but this isn’t an extravagant vacation — you’d pay $200,000 to start a new life on Mars after selling most of your possessions on Earth (cargo space is limited). Over time, that price might come down to as little as $100,000.
It’s not clear what sort of training would be needed for the mission, but Musk said it probably wouldn’t be much. Will those with health concerns be allowed to go? Will the colonists own land on Mars? The gravity on Mars is much lower, so will people be able to return to Earth with its high gravity after living on Mars? We don’t know the answer to any of these questions yet.
The Interplanetary Transport System would be multi-stage, but the first stage is designed to land itself back on Earth after getting the spacecraft into orbit, just like the Falcon 9. This booster is powered by 42 Raptor engines for 13,000 tons of liftoff thrust. Due to its size, the first launches will take place on the original Apollo 39A launchpad at Kennedy Space Center.
After it’s in orbit, several tankers of a similar design will be sent up to refuel the ship before it begins its Mars journey. Upon its arrival, the ship will land propulsively on the surface to drop off colonists and supplies. SpaceX chose to go with a methane fuel for the Raptor because that’s easier to make on Mars. The ships that deliver people won’t just sit there — they’ll be refueled and sent back to Earth. This will also allow colonists who have a change of heart to return to Earth.
Musk says that the Interplanetary Transport System will take 100 to 200 people to Mars at a time, and the journey could take as little as 80 to 90 days. There are launch windows to Mars every few years, and SpaceX wants to have fleets of multiple ships ready to go for each one. In a few decades, there could be a million people on Mars, which would be enough to make it self-sufficient.
SpaceX plans to start launching to Mars in the next year or two with Falcon 9 Heavy rockets and Dragon 2 landers. This will serve as the first phase of testing for the colonization efforts. The Interplanetary Transport System should begin orbital testing around 2020, and SpaceX wants to send it on test flights to Mars in the early 2020s.
That’s a very aggressive timetable, and we don’t have any information regarding how colonists would work to warm Mars or protect themselves from radiation. We might learn more as SpaceX begins transporting materials and supplies to Mars on the Dragon landers. Musk wants to have a Mars mission planned for every launch window to begin laying the groundwork for human habitation.
There’s still a lot that could go wrong. But colonizing Mars has never felt so real.