The shuttle was a dismal failure and the entire space advocacy industry should cheer at it’s departure. Waiting in the wings we have the Falcon 9 Heavy, Dragon & Orion, and the VF-200 engine. America and NASA are better positioned for human space exploration than they have been since the 1960s. Quite frankly at this point the only think holding NASA back is it’s reluctance to admit that.

And while Phil does well here, astronomer =/= rocket engineer, and I wish the press would stop confusing the two.

Sending humans anywhere is extraordinarily expensive, and I’ve yet to see something that could be done better by humans than by our deathless automatons. The price of a two way trip to Mars by humans could give us so many other robot missions to find out what is really worthy of direct human attention. And its not like the kind of research into getting robots to land on Mars, Titan, or a comet aren’t giving us any technological know-how too. Its a little different than you’d get from doing a manned mission, but its not like human missions are the *only* way to produce technological innovation.

This may well be true, as far as it goes, but you are making a flawed assumption – that it is a zero-sum game. If the impetus were to exist to support a manned Mars mission, we may quite easily end up with more robotic explorers than we have now. As a previous commenter mentioned, probably the best way to investigate the solar system is a combination of manned and unmanned vehicles.

the Voyager spacecraft will be passing from the Solar System into Outer Space, where, assuming the craft survive the new conditions, they may carry on for millennia, . . .

While they may indeed continue to drift for millenia, their RTGs only have about another ten or twenty years in them, so they will mostly be drifting as unpowered chunks of hardware.

1. Why not?

2. Because it’s there.

Why everyone in USA talks about Mars?

Well, at a wild guess, I’d say it’s because the Moon has been done.

NASA is the only organisation in the world that can say “been there, done that”.

Manned mission to Mars is orders of magnitude harder than Moon, and we even did not get back to Moon.

True, but so what?

Overcoming the challenges of a manned mission to Mars would open up the entire solar system, at least in principle.

Exhibit A: ISS. How often something breaks there? No repairmans on way to, on and from Mars, noooo sir!

Counterexhibit A : Apollo used multiply-redundant systems. The same would necessarily apply to a Mars mission.

However, your point is not so easily dismissed. Systems on a Mars mission would need to be designed to be fixable, and the mission would need to carry a boatload of spare parts.

Exhibit B: project Biosphere. Recycling? What recycling?

Yes, this is a challenge, and probably only limited recycling would be viable, but it need not be a show-stopper. After all, the ISS carries several months’-worth of supplies at a time.

Exhibit C: Curiosity. They said rover have first ever device to measure radiation levels on surface to Mars. What, isn’t that something that had to be done long ago, if someone seriously want go to Mars? How many other things that should be done aren’t done yet?

This is not a valid objection. Most of the radiation on the surface of Mars will be solar wind and cosmic rays, and we already know about these. A Mars habitat can be buried in the regolith, which would shield the occupants against most of the radiation. The bigger issue is radiation on the journey to and from Mars.

James Evans, don’t blame capitalism for short term competitiveness. That was around long before capitalism. If anything, the chain of causation is the other way around.

Yeah, no doubt, and being that there are subsidized markets in our hybridized version of capitalism that I personally wish were subject to sobering realities of free trade, I’m obviously not a devoted opponent. Still, the external costs it causes as a modern economic system don’t get enough attention. And for certain societal needs (such as frontier exploration), it should be regulated more often and to a greater degree than its most vocal beneficiaries are willing to admit, if not outright abandoned.