High Frontier can help Mars Direct

I tell students in my Space Colonization class that it would be far easier to make a garden (grow corn, tomatoes, potatoes, what-ever) in the Sahara and on the upper slopes of Mount Everest than on Mars. This is a good point. Sometimes when we ask Mars advocates why we will colonize Mars, the answer is, "Because of all the solar system bodies, it's the easiest to live on". But if"ease of living" were the only criteria, we would instead settlethe unexploited dry and cold places here on Earth. The only advantage a Mars settlement would have over such terrestrial settlements is that you'd be somewhere other than on Earth, if this all by itself were an advantage to anyone other than us space cadets. HF thinking, by contrast, is that we will live not where it's "easiest" to do so, but where the economic opportunities are. And that a garden in a green house on the Moon seems more likely to succeed than one on Mars, since there is less gravity and no winds on the Moon, the average temperature is higher, and it is days travel time from Earth rather than the months it is to Mars. I suspect you're right. Zubrin makes the opposite argument. He states that growing crops on any airless body is impossible because he assumes the glass would have to be sufficiently thick to screen out radiation. Of course that's not the method suggested by O'Neill, but we can leave space mirrors the size of cornfields right out of our thinking because that's just plain silly, to hear him say. But there's a fine print to his "plastic wrap" crop fields on Mars which require neither thick glass nor radiation shielding; one which Mars advocates sometimes overlook. It assumes a many-decades-long effort to thicken the Martian atmosphere via release of CF's at a rate comparable to current global production levels. As things stand right now (and for many decades to come), the pressure vessel for a Martian greenhouse would need to be no less sturdy than one for the moon or HEO. The chief difference would be the relative levels of insolation. Of course Mars does have a nearly24 hour day, but the 700 hour lunar day may work to an advantage for rapidly maturing crops. Experiments are needed here if they have not been done. I would be grateful for references on this question. Simulating 14 days of full-intensity sunlight using artificial illumination may be difficult (or power-consuming, at the very least). But it occurs to me that experimenting with raising plants in the solar intensity found on Mars ought to be high-school science fair level stuff. You'd think someone in the Mars Society would have performed this experiment long ago, but if they have, I've not heard tell. Maybe nobody's done it because they wouldn't look forward to the end results they'd probably get. I have been warming to the idea of colonizing the Moon. I don't want to subvert the goals of this group, but it might be useful to discuss that in detail. Discussion is fine, but I doubt I'll ever feel that the moon as a location for permanent settlement could effectively compete with orbital habitats. I feel that all the points which O'Neill made about the disadvantages of a planetary location apply to the moon. I'm sure the moon, as a nearby source of raw materials outside the steepest parts of Earth's gravity well, will see significant development. But I don't anticipate the moon being settled in a manner analogous to the settlement of the New World. The MD folks may not be open to considering colonizing "L-5" and not considering colonizing Mars, as Mark suggests, but they may listen to arguments about colonizing theMoon, especially if theyfeel they could learn valuable lessons to apply to Mars fromthoseplans. Most hold the moon in contempt (been there, done that), or attheir most generous allow that maybe it wouldn't be a bad place to put a few telescopes (still the wrong answer). They argue technical development of systems for the moon have little or no applicability to Mars.