Argument: Colonizing the Moon is not a logical step toward Mars
Gregg Easterbrook. "Moon Baseless". Slate. Dec. 8, 2006: "Don't we need a moon base to go to Mars? No! When George W. Bush made his Mars-trip speech almost three years ago, he said a moon base should be built to support such a mission. This is gibberish. All concept studies of Mars flight involve an expedition departing from low-Earth orbit and traveling directly to the red planet. Stopping at the moon would require fuel to descend to the lunar surface, then blast off again, which would make any Mars mission hugely more expensive. The launch cost of fuel—that is, the cost of placing fuel into orbit—is the No. 1 expense for any manned flight beyond Earth. The Lunar Excursion Module, the part of the Apollo spacecraft that touched down, was two-thirds fuel—all exhausted landing and taking off again from the moon. Rocket technology hasn't changed substantially since the 1960s, so a large portion of the weight of any Earth-to-Moon-to-Mars expedition would be dedicated to the fuel needed for just the layover. This makes absolutely no sense, and the fact that administration officials get away with telling gullible journalists that a Mars mission would use a moon base shows how science illiteracy dominates the big media. (It is imaginable that a moon facility could support Mars exploration by refining supplies from the lunar surface and then using automated vessels to send the supplies to the red planet, or to rendezvous with an expedition en route. But that's pretty speculative, and at any rate, the cost of building a moon base would far exceed that of simply launching the supplies from Earth.)"
John Glenn, NASA's first astronaut to orbit the Earth, said in 2008: "It seems to me the moon is questionable as a way station [to Mars]. If that's what we're doing – which I don't believe it is – but if that's what we're thinking about doing, that is enormously expensive." Mr. Glenn advocates a prominent alternative, which is to build a large space vehicle in Earth orbit and then accelerate it toward Mars, bypassing the need for a lunar outpost. "That to me would be the cheapest way to go," he added.
Donald A. Beattie. "Just how full of opportunity is the Moon?" The Space Review. February 12, 2007: "Human missions to Mars, if and when they might occur, are so far in the future that lessons learned on the Moon will have little relevance. If humans eventually travel to Mars, technology that would be used will be far advanced over that which NASA would employ on the Moon in the next twenty years. The first humans who might travel to Mars will probably not have the immediate objective of establishing a settlement. Rather, they will go as explorers and spend only that amount of time required to meet initial objectives, with their staytime defined by orbital mechanics. Determining how to utilize lunar resources to supply a lunar base will not have applicability to a Mars base as the technology and processes needed to use Mars raw materials will be unique to Mars resources. Other surface conditions on Mars that human explorers will have to cope with will also be much different than those found on the Moon and will require specific technology to ensure safe operations. Costly and risky human exploration of Mars may never be needed. As robots become more capable, the major scientific and philosophical question that drives Mars exploration—does life exist or has it ever existed on Mars—may well be answered by robotic missions. The need to establish human settlements on Mars in the future is problematic."