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Elon Musk: Future Round-Trip To Mars Could Cost Under $500,000
An anonymous reader writes with this quote from the BBC:
"Rocket entrepreneur Elon Musk believes he can get the cost of a round trip to Mars down to about half a million dollars. The SpaceX CEO says he has finally worked out how to do it, and told the BBC he would reveal further details later this year or early in 2013. ... 'My vision is for a fully reusable rocket transport system between Earth and Mars that is able to re-fuel on Mars — this is very important — so you don't have to carry the return fuel when you go there,' he said. 'The whole system [must be] reusable — nothing is thrown away. That's very important because then you're just down to the cost of the propellant.' ... He conceded the figure was unlikely to be the opening price — rather, the cost of a ticket on a mature system that had been operating for about a decade. Nonetheless, Musk thought such an offering could be introduced in 10 years at best, and 15 at worst."
Crikey. He could get that on kickstarter in about half an hour.
Probably something like this:
1) Use cheap SpaceX rockets to reach LEO.
2) Use multiple launches, carrying components of the Mars craft, the supplies, fuel, and crew on separate launches. This keeps you from needing a Giganto-rocket that ultimately couldn't lift as much as these separate launches anyway.
3) Transfer to Mars orbit (which is easier than getting to LEO)
4) Detach landing craft, land on Mars
5) Re-fuel with fuel conveniently pre-manufactured by previous robotic missions (this is the only part not obvious to me how it would be done for whatever that's worth).
6) Return to orbiter.
7) Return to earth.
LEO is the big obstacle. Earth's gravity well is a killer -- it's the largest of any rocky body in the solar system. If we can make LEO cheap and easy -- which just happens to be Elon Musk's major goal with SpaceX -- then we've made the rest of the solar system significantly cheaper and easier.
The enemies of Democracy are
Once you get into space you can also use other technologies for propulsion, like ion thrusters (low thrust.... but they can operate for a very long time with continuous thrust and insane specific impulse numbers) or even nuclear rocket engines like NERVA.
In theory, you can travel from the Earth to Mars in about six weeks and possible even less if you had the right engines. Yes, that takes a whole lot of energy.... but space is also full of a whole lot of energy too!
There are also things like Aldrin Cyclers and mission profiles that don't need to worry about how much mass is traveling between the Earth and Mars, so it becomes more like a cruise vacation on the journey complete with 5-star accommodations and staff along with entertainment. Those spaceships can literally be as big as you care... as large as any major cruse ship or larger. They can also be expanded to accommodate more passengers on each cycle or even have the construction crew "on staff" while in flight. It would be a bit of a trick to get the thing built initially, but the per passenger cost would be minimal and doesn't even need to worry about delta-v or even fuel at all and the staff can even be rotated out on each cycle. Food can be grown in such a vehicle, with air and water recycled as necessary... such a system is even being done on the ISS at the moment even though I'll admit it does need to improve to become practical on a larger scale. Solar arrays can be used for what energy needs such a vehicle might have. If you are going insane when running around a spaceship the size of a cruise ship, I can't help you out much. It may not look like a cruise ship, but then again stuff in space doesn't have to look like anything on Earth or even anything like what you've seen Hollywood come up with for spaceflight either.
In other words, it takes changing the notion of how things are done. The first few flights and getting the infrastructure set up are going to be expensive, but once that is built it doesn't have to be expensive for ongoing costs. The tough part is getting to and from the Earth to LEO or at worst to a "Earth Transfer Orbit" position. The sitting "as a sardine in a can" would only be for a couple days, and even then something like an Aldrin Cycler could be built to transfer between LEO and those other positions relatively near the Earth to get to the Earth-Mars cycler.
The idea that you are going to build a disintegrating pyramid starting from sea level at KSC bringing everything with you needed for the trip as you throw parts of your spaceship away is where the perception is flawed. Such a design methodology was useful in a wartime situation like how the Apollo program was built, but that doesn't need to be the only way to travel to other worlds. If anything, getting to the Moon with the Lunar Lander was about the limit of what you can do with chemical rockets flying on the disintegrating pyramid and Mars is simply unreachable. It is that mentality which creates the trillion dollar manned Mars missions too.