Yesterday, Elon Musk let us in on his plan to make humans a multi-planetary species. Though the simulation looks like it is from a hit sci-fi film, Musk assured the audience that he is serious about this endeavor and recommends that we get serious about it, too. In fact, SpaceX is already well on their way in developing the proposed Interplanetary Transport System (ITS), having already built one of the fuel tanks.
Why can’t we send people now?
Right now, using traditional methods, Musk says it would cost about $10 billion per person to send one person to Mars. His goal is to get that price down to about $200,000 (perhaps even less than $100,000, assuming optimization over time).
The ITS is a large, 200-foot-tall carbon-fiber structure. It has autogenous pressurization, meaning they gasify methane and use it to pressurize the gas tanks and gasify oxygen to pressurize the oxygen tanks. Their new booster is a scaled up version of the Falcon 9 booster (42 Raptor engines instead of 9).
Many engines means that if a few fail, you can still continue the mission.
Below is what the whole system and process look like in one snapshot. The large booster helps the ship get into outer space and then comes back down to land on Earth the same way Falcon 9 did earlier this year. The ship stays in orbit until a fueling vehicle is sent out to meet it and refuel it, and after refueling has finished, the ship continues carrying the passengers to Mars. Once the ship unloads the passengers on Mars, it has the ability to return to Earth for reuse.
One of the most incredible features of this whole system is how well optimized it is to utilize its size for the payload it needs to carry. Below is a chart of all of the vehicles we have used for space exploration by performance. The white bars show how much of the corresponding vehicle is utilized for its payload. Even the Falcon Heavy (3rd from the right) can only hold 54,400 kg of payload. The ITS (Mars Vehicle), however, can hold up to 550,000 kg of payload, utilizing ever inch of space in the system.
Hammering out a few details
All of this sounds simple enough, right? Well, as Musk stated in his presentation, we need to accomplish the following goals before we buy our tickets to Mars:
- Full reusability. In order to create a self-sustaining city on Mars, we need a foolproof system that will allow us to recycle fuel for reuse. Until we learn how to tap into other Mars resources, we’re going to need to figure out how to keep known resources going for a long time.
- Refueling in orbit. It looks cool in the simulation video, but it seems we’re not quite there with the technology yet.
- Producing propellants on Mars. There is a 500% increase in cost of the trip is we can’t figure out how to do this. We would also have a massive graveyard of ships if we don’t build a propellant plant on Mars and send our ships back to Earth.
- Picking the right propellant. According to Musk, this is an important decision. He argued that deep-cryo methalox (or methane) is the best answer because it’s cheaper than the other two options, kerosene and hydrogen/oxygen.
Many people have been saying things like, “That can’t be all we need to do. What about figuring out how people will live on the ship or on Mars?” Musk has said what he will do for us: get us to Mars. What soap people use on the ship or how to construct buildings on Mars once we get there are issues that he hasn’t yet agreed to take on (officially). SpaceX will build us a ship, and we will worry about hiring experts to help us survive on another planet when we know we will be able to get there. Until then, let us marvel at this beautiful simulation of the crew compartment on the ship:
At the end of his presentation, Musk said something that moved the audience to applause, “The main reason that I am currently accumulating assets is in order to fund this. So, I really don’t have any other motivation for personally accumulating assets except to be able to make the biggest contribution I can to making life multi-planetary.”
We appreciate it, Elon, we really do.
– Lydia Montagnese, @lydeey