Just to throw a hand grenade into the discussion - I honestly don't think it matters if people go to Mars - at least not right now. People can't live on Mars. Or on the Moon. Or anywhere else that we know of except Earth.

The distance between here and where ever the hell else in the universe people can live is so far, that in the absolute best case scenario it would take many, many, many times longer than written history to reach such a place using any propulsion system that we can currently imagine constructing.

Its a total fantasy. In order to make it a reality you need one of three things:

1. New physics.
2. Artificial BioSpheres that are sustainable for multiple generations.
3. Post-Humans.

You're not going to find any of these things on Mars. The first may not exist at all. The second is enormously risky, expensive, and far fetched. We're going to build cities under the sea long before we know how to build sustainable space craft that can last thousands of years, and we're aren't working on the former as far as I know. The later seems like the most likely bet.

We should be focusing on genetics and robotics - not space craft.

We'll build things with human like intelligence that can live comfortably in alien environments before we'll build vessels that enable humans to live comfortably in those same environments.

Decius wrote:
Just to throw a hand grenade into the discussion - I honestly don't think it matters if people go to Mars - at least not right now. People can't live on Mars. Or on the Moon. Or anywhere else that we know of except Earth.

That's just great Tom.. Just keep on destroying our childhood dreams, ok? :)

I will not be happy until there are large numbers of people living in space. We must hit the critical threshold, at which point the inevitable happens: The 0G Porn Industry

Decius wrote:

You're not going to find any of these things on Mars. The first may not exist at all. The second is enormously risky, expensive, and far fetched. We're going to build cities under the sea long before we know how to build sustainable space craft that can last thousands of years, and we're aren't working on the former as far as I know. The later seems like the most likely bet.

We should be focusing on genetics and robotics - not space craft.

I agree that putting humans into space at the present seems silly. Humans are not radiation hard, they are bulky, produce way too much waste mass, and it is extremely space consuming to convert solar or nuclear energy into human food.

Early space exploration has led to a very useful proliferation of satellites and some great engineering, so it seems like something worth *intelligently* continuing.

However, for the foreseeable future I think that space is for robots.

The fact that robotics isn't quite to the point where robots can replace humans in space seems like all the more reason to push hard on this and to develop robots that are excellent and versatile space explorers. The Mars Rover mission is a great example of a stunning and relatively cheap success.

Getting a (mostly) self-sufficient robot colony up in space would seem like a great alternative to ISS-like projects.

I find it interesting to note that the major commercial and applied uses of space today (communications, weather, surveillance, and telescopes) generally do not demand people actually going into space except for really spectacular repair missions.

Another nice thing about robots in space is that they don't need to get anywhere quickly, one can just send them out on the Interplanetary Transport Network and let gravity do all the work. They can wake back up when they arrive at the destination.

Getting really speculative, I can imagine robot fleets slowly drifting around various lagrange points and complex orbits to tug minerals to refineries in high orbit. There large solar arrays could be built for space-based solar power, and compute clusters fabricated to be powered and run massive calculations in space. All of this could have a dramatic benefit without the need to support human life in space or even deal with launch and reentry.