Our correspondent Anthony Barreiro has a letter in the current (August) issue of Sky & Telescope, objecting to the assumption that we must send humans to Mars. Doing so would be orders of magnitude more costly, and risky, than sending a fleet of investigating robots; and it is far more urgent to protect the garden of life we know we have here on Earth than to find possible microbes on Mars.
There is a further point to be made. Jim Loudon, who until he died contributed the section on space exploration in my Astronomical Calendar, wrote a lively opinion piece for Sky & Telescope (September 1987), countering the drive toward an early manned probe to Mars: “There might be life on Mars,” and we would never know, if we went there taking even one microbe that could escape and flood the planet. Hardware could be ruthlessly sterilized, but “You can’t boil an astronaut – union rules!” The possibility of any kind of life on Mars should be ruled out before any possible contamination be allowed there.
The general assumption in favor of Mars exploration continued, and once I wrote a letter to S&T myself, trying to point attention back to Jim’s well-argued essay.
I imagine that human presence at other planets will eventually come about, but far ahead, after more important problems have been solved, after it has become technically easier, and after it has been determined either that no alien life exists on them or we can be peacefully compatible with it.