All good points. The use of space resources you propose would very likely be the first use of space resources we'll see.

Not to belabor the point, but "dumb mass" for shielding from cosmic rays and solar proton events could also come from a mass driver on the Moon, and like the fuel could be joined with the Mars Direct space craft in orbit. And again, a win-win argument is needed and I think we have to stay with that and not close off discussion with other, maybe even dumb, space enthusiasts. It occurred to me a while back that there's a specific reason why we have a hard time convincing
Mars advocates that High Frontier type infrastructure in cislunar space would be of great value
to a major Mars effort. There are two places where the Mars advocate's mind likes to go. One is a near-term future
where Congress gets into an Apollo frame of mind once again and funds Mars Direct. Human
exploration of Mars begins, with the very first use of Martian resources beginning with in-situ fuel
manufacture for the trip home. The other place is a Mars of the distant future where a thriving, independent branch of human
civilization is present on the red planet. Obviously much has to happen between these two points. But the mind of the Mars advocate
tends not to go there. In their discussions, the narratives tend to move from the one place to the
other with hardly a sentence or two on the in-between eras. This contrasts with High Frontier thought, where a great deal of thinking and research has been
done on questions like how will we mine our first ten thousand tons of lunar/asteroidal ore, how
will we produce our first thousand tons of steel components, our first thousand tons of glass
windows, our first thousand tons of water and air, and how will we plant our first hundred acres
of crops. High Frontier infrastructure is of no benefit to Mars Direct, since it can proceed without so much
as reliance on a LEO space station. High Frontier is of no benefit to a fully-developed Martian
civilization of the distant future, as such a civilization is presumed to already be producing
everything it needs locally. Where HF would come in very handy is in the in-between stage, where we need to transport the
first thousand tons of mining equipment, ore processors and refineries, manufacturing facilities,
and construction equipment to Mars. Because if use of space resources and advanced
manufacturing were already taking place in HEO for other purposes, such facilities could provide
all these to a major Mars settlement effort for a fraction of the price of lifting it all out of the
steep gravity well of the Earth. But this is the era in history that the mind of the Mars advocate tends not to go to. And since they
don't often go there, they don't see any advantage to High Frontier.

Thank you Mike (Combs) for your thoughtful analysis of the Mars Direct mind-set (in RE: [ssi_list] High Frontier can help Mars Direct, May 11). Identifyingthe problems they overlook actually providesa list of opportunities for others to contribute to the future of space developments. I think it worth while to both help them to understandwhat is really possible and what is not, and also to help them solve any technical problems which can be solved. So, I think it would serve both our (the High Frontier) and MD objectives to articulate clearly what needs to be done to colonize Mars. 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. 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. 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. 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. 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. And maybe that way they will learn just how hard and expensive what they want to do will be. Should colonizing the Moonbe called Moon Direct? Wereally are prepared to proceed directly to that, and not directly to Mars. Or colonizing the Moon could be called Moon First? I plan to attend the Lunar Development Conference in Las Vegas this July to pursue this interest. In ancient times, both the Moon and Sun were referred as planets since they also wander (~planeta in Latin) against the back ground stars. Hence we have Sunday and Mo(o)nday as well as Satur(n)day, etc. I wonder if colonizing the Moon would rate higher if the Moon were still called a planet, and if so, if we should start calling it thatagain. Sincerely, Jay Huebner

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.

class7062318-11052001>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

In response to sentences from my earlier e-mail and Mark's e-mails under the above title:" 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 insulations." There were studies of how nuclear or ionizing radiation (which is what cosmic rays are) effects plants 35 to 40 years ago, and the results are that plants can take powers of ten more than animals can. There was a Scientific American article on this, and I am sure a lot of more detailed articles then and since. Meaning gardens can grow with shielding from cosmic radiations, but the gardeners must limit the time they spend in their unshielded gardens. From what Mark said, Zubrin is way off on this. There are other issues for a "plastic wrap" garden on Mars. Mars has no oxygen in its atmosphere and so no ozone protection from the hard solar ultra-violet radiation. Plastic left outside on Earth breaks down in a few months or years from the soft ultra-violet which gets through our ozone layer. Exposed plastic wrap would rapidly be destroyed on Mars. Another issue for gardens everywhere that use "regolith" for soil, is oxygen. When green cells first started producing oxygen from photosynthesis onEarth, the oxygen was consumed in oxidizing the iron and other materials in Earth's surface, so essentially no free oxygen appeared in the atmosphere for millions of years. The soils of Mars, the Moon and asteroids, will be a sponge for oxygenalso, and plantsrootsmust have oxygen in the soil or the roots will die. Roots of green plants use oxidative respiration like we do, consuming oxygen and sugars, to stay alive. The green plant parts above the ground produce oxygen only when "the Sun shines", but when in the dark they also consume oxygen. Studies on soy beans suggest that they do best with about 5 % oxygen. And, in response to " 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." My thinking about the High Frontier (and O'Neill habitats) is that they are the only way to achieve the full potential of space, but I suspect there is a roll for a lunar colony in the near future. Sort of like St. Louis, Missouri in opening the western part of the United States. St. Louis served both those going to Kansas and California, and I can see that the Moon could serve those going to O'Neill habitats in cis-lunar space, to highly eccentric Solar orbits, Mars, the main belt asteroids, the Trojan asteroids, and where-ever. Best wishes, Jay Huebner

In a message dated 5/12/01 3:36:54 PM Eastern Daylight Time, jhuebn@...
writes:

> Should colonizing the Moon be called Moon Direct?

Please excuse my typo in a previous message. I meant to say, "Meaning gardens can grow with OUT shielding from cosmic radiations, but the gardeners must limit the time they spend in their unshielded gardens." The OUT being left out. A factoid on the issue of cosmic rays and life on Earth to illustrate that this topic is well known, though I am not an expert in it. We are protected from cosmic rays by the Earth's magnetic field andthe atmosphere. The Earth's magnetic field periodically dies and then comes back in the reverse polarity. That exposes all life on the Earth's surface to an increased flux of cosmic radiation, and we have survived that manytimes, though there are statistically more new species in the fossil record just after (above) such reversals, suggesting an increased rate of mutations from an increased cosmic ray flux driving evolution a little faster then. With regard to "Some plastics may degrade faster than others. The plastics we use on Mars don't have to last for all of eternity, they only have to last long enough to grow plants. There is no short supply of glass on Mars either. I had a plastic greenhouse once and had to replace the plastic every year." In the hard solar ultra violet (with no ozone layer protection), mostplastics will go fast. Changing (i.e. rebuilding) the greenhouses on Mars several times in a growing season isnot like replacing the plastic on a terrestrial greenhouse in the off season. The ultra violet and loss of the atmosphere while changing the plastic on Mars may kill the crops. Remember an open container of ice water will boil on Mars. What garden plants can stand that? And Martian windstorms are nothing to ignore either. Greenhouses made of glass would require much more investment than a "plastic wrap" garden. Is there some dishonesty here? To be straight out, it would seem that the possibilities are either dishonesty or ignorance, which have different motivations, but would have similar consequences to those depending on the crops. One needs to try these ideas out on Mars before risking many lives and many trillions of dollars on plans based on them. In my view, just testing these ideas out on Mars would cost more than a whole colony on the Moon or at L-5. In fact,probably the best place to try out a proposed Martian greenhouse would be on the Moon. Which is where I came in on this. I may join some other groups, thanks for the tips and URLs on the Moon groups, but I am too busy just now to look into them very much. I wrote O'Neill in the fall of 1974 and got a response from him suggesting some sort of organization be formed. As a result I was the 38th member of The L-5 Society, which made me a member of the National Space Society when it was formed. I was also a member of the Space Studies Institute for many years. As that illustrates, organizations can beuseful. They are about the only way anything gets done. But for now, I need to work on tasks for other organizations I belong to, one ofwhich pays my salary. Sincerely, Jay Huebner

Most people on this list seem to agree that the moon should be our next port of
call. I would certainly agree with that, but for different reasons. Mars
certainly is a far friendlier place than the moon. I have heard estimates that
ionising radiation levels at the Martian surface, are a factor of three less
than those at the moons surface. It also seems likely that plants can be grown
under plastic greenhouses on the Martian surface (as long as those greenhouses
are coated with a UV filtering substance). It is also true to say that Mars is
an infinitely richer world than the moon. Compared to the moon, Mars possesses
mountains of water, sulphur, carbon, nitrogen and virtually every other element
needed for life.
The moon, in comparison, is an impoverished world. The moon is highly
depleted in volatile substances. Many of the elements that are essential to
human life, are almost entirely absent on the moon. Many of the metals that are
essential in modern industry, are extremely hard to come by on the moon.
But the fact remains that no matter how nice Mars may look, it is not in the
position to act as an exporter of goods. This is an extremely important point
and most MD supporters seem to overlook it. As an exporter, the moon is in an
exceptional position. Low gravity, no atmosphere and only 1.28 light seconds
away from Earth.
The only question is, where do we obtain the large quantities of carbon,
nitrogen, phosphorus, hydrogen and the plethora of other substances, that would
be required by lunar or L-5 industry? The only possible source of such materials
would be the asteroids. An elegant solution to the problem, would be to trap a
large asteroid at the L-4 point on the moons orbit.

I have heard estimates that
ionising radiation levels at the Martian surface, are a factor of three less
than those at the moons surface. The figures that I've heard suggest that Mars may be a factor of two to three less than free space. I suspect the moon would be a factor of two belowspace (half of your surroundings is blocked by the moon), so I think Mars has a slim margin over the moon. That to me makes sense, since the only thing Mars presently has over the moon is an atmosphere only 1% as dense as ours.

> The moon, in comparison, is an impoverished world. The moon is highly
> depleted in volatile substances. Many of the elements that are essential to
> human life, are almost entirely absent on the moon.

>>>Which ones were you thinking of here?>>> Manganese, Copper, Germanium,
Arsenic, Gold, Silver, Lithium, Beryllium, Strontium, to name just a few. Of
course you are correct, these substances may be concentrated locally, within
meteorite craters, but we cannot simply assume that they do exist. Assuming that
there are no such local concentrations, we are going to need to find a
supplementary source of these materials. The obvious source would be a near
earth asteroid.

In a message dated 5/14/01 9:00:58 AM Eastern Daylight Time, mikecombs@...
writes:

hollroa@... wrote: The only question is, where do we obtain the large quantities of carbon,
nitrogen, phosphorus, hydrogen and the plethora of other substances, that would
be required by lunar or L-5 industry? The only possible source of such materials
would be the asteroids. An elegant solution to the problem, would be to trap a
large asteroid at the L-4 point on the moons orbit. I have been thinking about how to do this. I started a discussion node at http://www.innertransit.org/secure/ibisview.php?IBISnodeid1> for Tethered Momentum Transfer Intercept. Anybody who would like to add comments feel free to sign in.
Mitchell James
mejames@...
http://www.innertransit.org (homebase for collaborative engineering)

In regards to "On Phobos there is a crater called Stickney that is always
facing Mars, I wonder if Mars would fill the whole sky as seen from the
bottom of Stickney crater. If so then this would be a natural radiation free
area since the
crater walls would protect from the sides, Phobos would shield from below
and Mars would block radiation from above."
If no radiation gets is, then there would be no sunlight getting in either,
and agriculture would be impossible. But you-all have missed the point I
made, namely that agriculture will not be hindered by cosmic rays. Factors
of 1/2 or 1/3 won't change that. Plants can take it. Another point ignored
is that plant roots need oxygen. We can ignore that but the plants won't.
They'll die. And the oxygen partial pressure needed to make soy beans do
well is about 5 times the Martian atmospheric pressure. This means there
will have to be a gas tight floor below the soil, the soil will have to be
treated to either take out the iron and other materials which will combine
with oxygen, or substantial oxygen will be lost to these reactions, and the
"plastic wrap" greenhouses will have to be under significant pressure,
oxygen, water vapor plus carbon dioxide.
Sincerely, Jay S. Huebner at jhuebn@...

>>>Another point ignored
is that plant roots need oxygen. We can ignore that but the plants won't.
They'll die. And the oxygen partial pressure needed to make soy beans do
well is about 5 times the Martian atmospheric pressure. This means there
will have to be a gas tight floor below the soil, the soil will have to be
treated to either take out the iron and other materials which will combine
with oxygen, or substantial oxygen will be lost to these reactions, and the
"plastic wrap" greenhouses will have to be under significant pressure,
oxygen, water vapor plus carbon dioxide.>>>

> With regard to "Some plastics may degrade faster than others. The
> plastics we use on Mars don't have to last for all of eternity, they
> only have to last long enough to grow plants. There is no short supply
> of glass on Mars either. I had a plastic greenhouse once and had to
> replace the plastic every year." In the hard solar ultra violet (with
> no ozone layer protection), most plastics will go fast.