In 2004, President Bush presented a new agenda for NASA that included human missions to the moon and Mars. The report is in the President’s Commission on Moon, Mars and Beyond. I grew up during the space age and one of the most inspirational moments of my life was witnessing Neil Armstrong walking on the moon in 1969. It certainly was a factor in my decision to pursue a career in science. However, I now firmly believe that manned space flight is intrinsically flawed and should not be supported by the government.
The reasons are two fold. The first is that there is no scientific purpose that requires humans and the second is that humans are very badly adapted to space. Other than bringing back moon rocks (which could now be done with robots) and fixing the Hubble telescope (which could soon be done by robots), there has been no contribution to space science from human exploration. The only science that has been done is the study of the effects of space on humans and the conclusion is that we don’t belong there. The weightlessness causes severe muscle atrophy and bone loss. Even more problematic is the high levels of ionizing radiation present in space. The extra cost required for human over robotic missions is astronomical.
The only reason we should go to Mars is the same reason we should climb Mt. Everest. I think this is perfectly fine and honourable but I don’t think we should support such a junket with federal dollars. Let some maverick billionaire fund the operation. By the time we actually have the technology to be able to colonize other planets or even go beyond the solar system our knowledge of biology and artificial intelligence will have also greatly advanced. Instead of sending people we could send human embryos or better yet just the genetic codes. Once we arrive at our destination we can simply grow our colonizers from available organic molecules. Robots could raise and educate the first generation. This seems far more sensible than sending people in a lead lined cabin or putting them in suspended animation (at least until we get that Star Trek warp drive, force field and artifical gravity generator working).