[jkimmel]

I'm bullish on SpaceX when it comes to launch systems and vehicles, but to the best of my knowledge they haven't demonstrated any expertise in Life Support Systems.

The hardest part about getting to Mars isn't flinging a metal tube off the Earth. That part we know how to do.

The hard part is keeping people alive for 6 months there, 6 months back, and providing all the equipment necessary to do meaningful science on the surface.

This isn't to say that an adequate launch system isn't essential to the mission, but I would be very surprised if SpaceX developed life support systems independently and more efficiently than NASA. More likely, I can imagine a news headline in which a SpaceX rocket sends a NASA capsule and living module to an off-world mission.

[Joeri]

Why wouldn't SpaceX be capable of doing life support systems? What's so magically complicated about those compared to the rockets themselves? You have to be aware of the shifting goal posts scenario here. At every stop people said SpaceX wasn't going to be able to do what they were going to do, because there was some kind of magic fairy dust that only government space organizations have. And each time that they achieve a milestone, people just keep shifting the goalposts. They've already done things NASA was never able to do, like build a reusable rocket and land it vertically. Clearly they are more capable than NASA in some ways. Personally, I think SpaceX will be able to do everything they say they will do, up to and including putting people on Mars. They've come this far, why wouldn't they go all the way?

[jccooper]

That's about entirely backwards. Flinging a metal tube off of Earth is much harder than keeping a few apes alive in a can. The tolerances and requirements in rocketry are much more severe, the dimensions unfortunately super-human scale, and the ability to test the system limited by the scale, expense, and speed of the final product, not to mention the usually-100% chance of destroying your machine in the process. (Even reusable systems, which are rare, are expensive to run simply due to scale.)

The actual spacecraft part is easy in comparison. It's of reasonable dimension, you can test and fiddle with it on the ground, and plenty of common practice is available due to submarines and high-altitude aircraft as well as decades of continuous operation in space.

The history of manned space systems will present plenty of examples of the booster being the pacing element. But we don't have to look much further than the very system we're talking about here. Orion is ready and flying a projected 4 years (and probably longer in reality) before its booster. And that's not because they got a head start.

That's not to say that rockets and manned space craft are similar problem domains; they're not. Any expertise SpaceX will need in that area will have to be developed separately. But the techniques are well known (thanks largely to NASA, who make no secret of it) and are just plain not that hard. They're already flying a pressurized and temperature-controlled Dragon (which spends time as part of the ISS), and are in development of a crewed one.

It is true that SpaceX has yet to operate any space stations, which NASA has, and which are the closest analogues we have to an interplanetary spacecraft. But again, ISS systems are a known quantity, and SpaceX could easily replicate them. Or, if they don't want to bother, could contract with Bigelow, who is currently flying two (unmanned) pressurized space stations, with designs for manned versions ready to go and awaiting a way to get there. SpaceX and Bigelow have already announced plans to partner for orbital station operations.

A Dragon and a Bigelow station would provide a nice ride to Mars. Getting to the surface and back would be a bit of a problem, but a SpaceX/Bigelow team could possibly land on Phobos and return in the next 5 years. And on a darn low budget, too. If you want to walk on Mars without too much tech development, Dragon 2 should be able to land just as it does on Earth. Dunno how you'd get back up, though. Maybe you could land a Falcon-ish booster loaded with a storable oxidizer (like peroxide) on little enough juice that it could get back into orbit. Haven't looked into the numbers there; F9-1 is certainly single stage to orbit on Mars, but down-and-up on the same fuel load seems unlikely. It'd certainly work with ISRU propellants, but that's a nice can of worms.