Much much more science can be done for the same price if you omit the humans. The commercial viability threshold is much much lower if you omit the humans. The one and only reason to send humans up to space in the foreseeable future is patriotic chest thumping. Well that and to stroke the adolescent fantasies of those who grew up on science fiction.
Tyson, an astrophysicist and director of New York City's Hayden Planetarium,
agreed with his interviewer in saying that "the manned program is a force
of nature on the educational pipeline of America. It is the force that excites
people to want to become scientists in the first place." [1]
[1] http://www.space.com/8184-robots-humans-space-colbert-tyson-...
Even if true, there are likely far more cost-effective ways of generating the same interest, either with robots or other educational programs. I don't see why a robotic program can't be inspirational. And anyway we don't have any shortage of scientists right now.
Not ever. It's never going to happen.
So the comparison is pointless.
The only way you'll ever get that level of funding is to send humans, and now and for the foreseeable future, humans are going to be much more capable. Notice I didn't say efficient, because again, efficiency is a moot point. Efficiency only matters if you get the same scale of funding. And that's just never going to the be case.
It's pure fantasy to think otherwise.
That's okay, there's plenty of other worthy things to spend government money on. If it's manned or bust, I'll take bust. Maybe a future generation won't be so childish.
The Moon is days of travel time, whereas Mars is months of travel time. Round-trip communication delay to the Moon is seconds. Delay to Mars is minutes. Pieces of the Moon can be returned as souvenirs. Delta-v for returning bits of Mars is ridiculous. People can SEE the Moon with the naked eye, even in urban light pollution. Mars requires a map of the sky and a pair of binoculars, at least.
The Moon is important because it motivates the nonscientific people of Earth to support more productive forms of space exploration research. It reminds people that this is not only a very small world, but the only one we have. And it creates a seed economy with a shorter possible cycle of iterations than a few missions clustered around the same 3-month launch window every 780 days. There is some merit to having regular shorter missions to a closer target, so that when that window comes around, you have people with steady jobs and experience around to run the longer missions.
It isn't just about the scientific benefit. You also have to consider the human factors. Nobody wants to train for years to be unemployed 90% of the time, waiting around for the next time someone needs some specific skill. The thing about Moon missions is that they can be done with resources that would otherwise be mothballed and rusting, or used once and discarded.
Manned Mars missions aren't any more "productive" than manned Moon missions. Both are terribly inefficient from any scientific or commercial perspective.
Star Trek succeeded as a television show because it had human actors telling a story, to the point that this fiction is more popular as an entertainment franchise than actual space exploration? Why? Actual space exploration has only produced a handful of biplanetary pedestrians, and only John Glenn has made any kind of a big deal about it.
In my view, the end goal of space exploration is to transplant Earth-origin life to other planets--not just humans, but (at minimum) thousands of species. That goal is not served by ignoring the transporting-the-biologicals portion of space exploration. That means I am completely unwilling to fund with my dollars any scheme that allows other people to fritter away money on pure science that will never become applied science, specifically science applied to my personal lifestyle. Multiply me by the six billion people who will likewise never escape our gravity well, and you had darned well better start thinking about the politics and the economics along with the science.
In short, I don't give a fig about whether it would make the boffins happier to do something else. Humans in space is what I am willing to pay for. If they don't want to play along with my non-optimal prejudices, I'd prefer that they be cut off from tax-derived funds entirely, and go with exclusively private funding. Ask for public money; act in the public's interest. The public is interested in seeing people in space.
It IS stupid, and doesn't make sense. What else would make it a uniquely human endeavor?