Men on Mars

[Brigliadore]

Originally posted by tw
Eventually, when robots find a reason, then man will go to Mars.

Scientific American Magazine, has an article titled Why go to Mars? that has some of those "logical" reasons that TW is looking for on why to send humans to Mars vs robots. For those that don't want to read the 4 page article I am posting some quotes relevant to what we have been discussing.

"...A thorough hunt for any Martian life that might be hanging on--—despite the present harsh conditions--would also have to be undertaken by humans, according to some experts. Such life will be hidden and probably microscopic, says Pascal Lee, a research associate at the NASA Ames Research Center. "Finding it will require surveying vast tracts of territory," he explains. "It will take a high degree of mobility and adaptability." Robots might be up to the task sometime in the distant future, Lee concedes. But relying on them to survey Mars completely for life would take an unrealistically long time--"decades if not centuries," he believes.
To accomplish the same scientific goals as a series of human missions, far more robotic missions--and therefore launches--would be required. The greater number of launches would mean that the robotic program would take much longer, because opportunities to travel from Earth to Mars are rather limited. They occur only once every 26 Earth-months, when the planets are positioned so that the trip takes less than a year...."

"...Another reason why humans may have to be on site to conduct a thorough search for life stems from the fact that if any such life exists it is probably deep underground. Mars's atmosphere contains trace quantities of a strong oxidizing agent, possibly hydrogen peroxide. As a result, the upper layers of the soil are devoid of organic matter. So most strategies for microbe hunting involve digging down to depths where life or organic matter would be shielded from the oxidizing agent as well as from searingly high levels of ultraviolet light.

Upcoming probes will be equipped with robotic assemblies that can bore several centimeters into rocks or dig a few meters down into the soil. But barring any discoveries at those shallow depths, researchers will have to bring up samples from hundreds of meters below the surface, maybe even one or two kilometers down, before they can declare Mars dead or alive. Drilling for samples at such depths "most likely will require humans," says Charles Elachi, director of the Space and Earth Sciences Program at the Jet Propulsion Laboratory in Pasadena, Calif...."

"...Although a human mission would be more expensive, it would also be more cost-effective, Zubrin insists. He concedes that sending astronauts to collect geologic samples and bring them to Earth would cost about 10 times more than sending robots. But by his calculations the human mission would return 100 times more material gathered from an area 10,000 times larger.
On the other hand, Arden L. Albee, a former chief scientist at JPL and the project scientist for the Global Surveyor mission, cites a 1986 study by NASA's Solar System Exploration Committee that determined that a robotic mission could have accomplished all the geologic sampling carried out on the moon during Apollo 15. In one day during that mission, astronauts David R. Scott and James B. Irwin drove a rover 11.2 kilometers, collecting samples at five stations. They picked up 45 rocks, 17 loose soil samples and eight firmly packed soil "cores." A robotic rover could perform much the same work, the study found, but it would take 155 days to do so..."

I rest my case.