Problems of Sustaining Settlements on Mars: Somewhere to Live.

People who write science fiction find colonizing Mars to be a fruitful source of plot material. Kim Stanley Robinson wrote three books on the topic, ending up by terraforming Mars. I have also written one (“Red Gold”) that included some of the problems. We even have one scheme currently being touted in which people are signing up for non-return trips. So, what are the problems? If we think about settlers making a one-way trip to New Zealand, as my ancestors did, they would find a rough start to life because much of the land was covered in forest, although there were plains. But forests meant timber for houses, some fuel, and even for sale. Leaving aside the stumps, the soil was ripe for planting crops, and you could run sheep or cows. It would have been a hard life, but there would be no reasons to fear instant death.

Mars is different. It has its resources, but they are in an inconvenient form. Take air. Mars has an atmosphere, but not a very dense one. The air pressure is about two orders of magnitude less that on Earth. That means you will have to live in some sort of dome or cave, and pump up the atmosphere to get adequate pressure, which requires you to build something that is airtight. The atmosphere is also full of carbon dioxide, and has essentially no oxygen. The answer to that is simple: build giant glass houses, pump up the atmosphere, and grow plants. That gives you food and oxygen, although you will need some fairly massive glass houses to get enough oxygen. So, how do you go about that? You will need pumps to pump up the air pressure, some form of filters to get the dust out of the inputs, and equipment to erect and seal the glass houses. That will need equipment brought from Earth. Fortunately you can make a lot of glass houses with one set of equipment. However, there are three more things required: glass, metal framing, and some form of footer, to seal in the pressure and stop it leaking back out. Initially that too will have to come from Earth, but sooner or later you have to start making this sort of thing on Mars, as otherwise the expense will be horrendous.

Glass is made by fusing pure silica with sodium carbonate and calcium oxide, and often other materials are added, such as alumina, magnesium oxide, and or borate. It is important to have some additives because it is necessary to filter out the UV radiation from the sun, so silica itself would not suffice. It is also necessary to find a glass that operates best at the lower temperatures, and that can be done, but how do you get the pure ingredients? Most of these elements are common on Mars, but locked up in basaltic rock or dust. The problem here is, Mars has had very little geochemical processing. On Earth, over the first billion years of ocean, a lot of basalt got weathered by the carbonic acid so a lot of magnesium ended up in the sea, and a lot of iron formed ferrous ions in aqueous dispersion. The earliest seas would have been green. Once life learned how to make oxygen, that oxidized the ferrous to ferric, and as ferric hydroxide is very insoluble, masses of iron precipitated out, eventually to dehydrate and make the haematite deposits that supply our steel industry. Life also started using the calcium, and when the life died and sunk to the bottom, deposits of limestone formed. As far as we know, that sort of thing did not happen on Mars. So, while sand is common on Mars, it is contaminated with iron. Would that make a suitable glass? Lava from volcanoes is not usually considered to be prime material for making glass.

So, how do you process the Martian rock? If you are going to try acid leaching, where do you get the acid, and what do you do with the residual solution? And where do you do all this?

While worrying about that, there is the question of the footer. How do you make that? In my novel Red Gold I assumed that they had developed a cement from Martian sources. That is, in my opinion, plausible. It may not be quite like our cement, which is made from limestone and clays heated to about 1700 degrees C. However, some volcanic eruptions produce material which, when heated and mixed with burnt lime make excellent cements. The main Roman cement was essentially burnt lime mixed with some heat-treated output of Vesuvius. Note once again we need lime. This, in turn, could be a problem.

My solution in Red Gold to the elements problem was simply to smash sand into its atoms and separate the elements by electromagnetism, similar to how a mass spectrometer works. The energy input for such a scheme would be very high, but the argument there was they had developed nuclear fusion, so energy was not a problem, nor for that matter, was temperature. No molecules can survive much more than about ten thousand degrees C, and nuclear fusion has a minimum temperature of about eighty million degrees C. Fine, in a novel. Doing that in practice might be a bit more difficult. However, if you don’t do something like that, how do you get the calcium oxide to make your cement, or your glass? And without a glass house, how can you eat and breathe? Put you off going to Mars? If it hasn’t, I assure you once you have your dome your problems are only beginning. More posts on this some time later.

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Why Are Countries Separating?

In many of my futuristic novels, I have selected a form of government to be in the background. Thus I have had a theocracy, a dictatorship, essentially no government (for the initial settlement of Mars), anarchy, crumbling “democracy” (i.e. our representative republic), real democracy, and finally, something else that I shall call federalism. The concept behind federalism is that a number of countries willingly join a Federation, and on most issues they continue on as they have always done, but there was also an over-riding Council whose function is to set a limited number of rules, and act as referees to make sure the various politicians in the countries behave. Another function is to provide factual information, and prevent political movements from achieving goals by lying. (Hey, I thought about “fake news” before it was popular, but that of course is hardly true either. Telling lies to get votes was bread and butter for the politicians of the Res Publica, and many of the inscriptions on the walls of Karnak by Ramses II had little relation with the facts.) This Federation also has to deal with the futuristic problems that we can see now, such as energy availability, resource allocation, climate change, etc. Interestingly enough, at least for me, the problems upon which the novels depended invariably arose from a similar source: people gaming the system. That may merely reflect my lack of imagination, but I rather fancy that any system will work well if all the people try to make it work. Most Romans thought Augustus was a great leader, even though he was effectively a dictator and probably the greatest manipulator ever.

The plots of these novels focused on how people were trying to get around the various rules. If there were an underlying message here, it was that rules only really work when people can see the point in them. A classic example is road rules. I suspect most of us have, at some time broken the speed limits, and while I have no intention of being specific and attracting unnecessary tickets, I know I have. I actually try to obey parking limits, but some times, well, something happens and I can’t quite make it. However, wherever I am, there is a rule on which side of the road I should drive on, and I keep to that assiduously. There is no specific preference – some countries drive on the right and others drive on the left, but a country has to choose one and stick with it, otherwise there are messy collisions all over the place. Everybody sticks to that rule because they see the point. (Confession time – once I did not. I came over a rise in Czechoslovakia, it was pitch black, and there was a little fire to my left. Suddenly, I realized the problem – there was a tank with camouflage netting parked in the middle of the road. I evaded around the left, not the right, because being in a British car I could better see the space I could use on my right, and also because I was better trained in sliding on gravel, etc, at speed and getting back on the road from that side. Must have given the tankers a bit of a fright. They would see a car first coming straight at their tank at 100k, then it would evade towards them and start sliding sideways, sending up showers of gravel from the side of the road.)

However, the point is, in general people will happily accept such rules if they see a point to them. Which side of the road you should drive on has a very clear point. The speed limit, perhaps less so. We recognize that road construction usually requires speed limits but I know that in some hilly terrain, overtaking a truck would be more important than sticking to a number. The problem with such rules, though is the rule makers seem to get carried away and think there should be rules for everything.

Some may recognize this Federal system. I made it up in the 1980s, and I was inspired in part by the European Union. You may recall at that time there was talk of the currency being the ecu, or European Currency Unit. Accordingly, in my novels I invented the fecu, however I put in one rule that Europe ignored. (They should have consulted me!!) In the novels, the fecu is used for transactions between companies and major corporations, and has a fixed value, a sort of resource standard. However, salaries in different countries, and goods in different countries, are paid in dollars, drachmas, whatever, and the average citizen never sees a fecu. I think the euro is a weakness of the EU because I don’t think you can run a common currency when countries have different economic policies.

Another question is whether the UE, through Brussels, has too many rules. Some say yes, others say no, but in the various discussions on Brexit, there is a lot of talk about untangling the thousands of rules. If that is a problem, there are too many of them. Good rules have a wide acceptance, and they could stay.

Which naturally brings me to the French election. All the commentators I have read say the French were upset over EU rules, and wanted change. So, what do they do? They elect a plutocrat, a banker! Trust the French – reminds me of “plus ça change, plus c’est la même chose” (Jean-Baptiste Alphonse Karr) which translates out as “the more it changes, the more it is the same thing”. So, how do you get rid of the rule of plutocrats? The French elect one. The British go the indirect way and try the “go it alone” way. Neither will probably work, but in answer to the title question, I think it is because so many voters have given up on traditional representatives acting in the interests of the population at large they are prepared to try anything.

Settling Mars and High Energy Solar Particles

Recently, the US government announced that sending people to Mars was a long-term objective, and accordingly it is worth looking at some of the hazards. One that often gets airing is the fact that the sun sends out bursts of high-energy particles that are mainly protons, i.e. hydrogen atoms with their electrons stripped off. If these strike living matter, they tend to smash the molecules, as they have energy far greater than the energy of the chemical bond. These are of little hazard to us usually, though, because they are diverted by the earth’s magnetic field. It is this solar wind that is the primary cause of auroras. The solar wind particles knock electrons out of gas molecules, and the light is generated when electrons return. As you might guess, if these particles can knock out enough electrons from molecules to generate that light show, the particle flux would be quite undesirable for DNA, and a high cancer rate would be expected if some form of protection could not be provided.

The obvious method is to divert the particles, and electromagnetism provides a solution. When a charged particle is moving and it strikes a magnetic field, there is a force that causes the path of the charged particle to bend. The actual force is calculated through something called a vector cross product, but in simple terms the bending force increases with the velocity of the particle, the strength of the magnetic field, and the angle between the path and the magnetic field. The force is maximum when the path is at right angles to the magnetic field, and is actually zero when the particle motion is parallel to the field. The question then is, can we do anything about the solar particles with this?

The first option would be to generate a magnetic field in Mars. Unfortunately, that is not an option, because we have no idea how to generate a dynamo within the planet, nor do we know if it is actually possible. The usual explanation for the earth’s magnetic field is that it is generated through the earth’s rotation and the iron core. Obviously, there is more to it than that, but one thing we know is that the density of Mars is about 3.9 whereas Earth is about 5.5. Basalt, the most common mix of metal silicates, has a density ranging from 3 to 3.8, but of course density also increases with compression. This suggests that Mars does not have much of an iron core. As far as I am aware, it is also unclear whether the core of Mars is solid or liquid. Accordingly, it appears clear there is no reasonable hope of magnetizing Mars.

The alternative is to put an appropriate magnetic field on the line between Mars and the sun. To do that, we have to put a properly aligned strong magnetic field between Mars and the sun. The problem is, bodies orbiting the sun generally only have the same angular rotation about the sun as Mars if they are at the same distance from the sun as Mars, or on average if they are orbiting Mars, in which case they cannot be between, and if they are not between all the time, they are essentially useless.

However, for the general case where a medium sized body orbits a much larger one, such as a planet around a star, or the Moon around Earth, there are five points where a much smaller object can orbit in a fixed configuration with respect to the other two. These are known as Lagrange points, named after the French mathematician who found them, and the good news is that L1, the first such point, lies directly between the planet and the star. Thus on Mars, a satellite at L1 would always seem to “eclipse” the sun, although of course it would be too small to be noticed.

Accordingly, a solution to the problem of high-energy solar particles on settlers on Mars would be to put a strong enough magnetic field at the Mars sun L1 position, so as to bend the path of the solar particles away from Mars. What is interesting is that very recently Jim Green, NASA Planetary Science Division Director, made a proposal of putting such a magnetic shield at the Mars-Sun-L1 position. For a summary of Green’s proposal, see http://www.popularmechanics.com/space/moon-mars/a25493/magnetic-shield-mars-atmosphere/ .

The NASA proposal was focused more on reducing the stripping of the atmosphere by the solar wind. If so, according to Green, such a shield could help Mars achieve half the atmospheric pressure of Earth in a matter of years, on the assumption that frozen CO2 would sublimate, thus starting the process of terraforming. I am not so sure of that, because stopping radiation hitting Mars should not lead to particularly rapid sublimation. It is true that stopping such charged particles would help in stopping gas being knocked off the outer atmosphere, but the evidence we have is that such stripping is a relatively minor effect.

The other point about this is that I made this suggestion in my ebook novel Red Gold, published in 2011, which is about the colonization of Mars. My idea there was to put a satellite at L1 with solar panels and superconducting magnets. If the magnet coils can be shielded from sunlight, even the high temperature superconductors we have now should be adequate, in which case no cooling might be required. Of course the novel is science fiction, but it is always good to see NASA validate one of your ideas, so I am rather pleased with myself.

Why is the Moon so dry?

The Planetary Society puts out a magazine called The Planetary Report, and in the September issue, they pose an issue: why is there more water ice on Mercury than the Moon? This is an interesting question because it goes to the heart of data analysis and how to form theories. First we check our data, and while there is a degree of uncertainty, from neutron scattering as measured from orbiting satellites, Mercury has about 350 times the water than the Moon, not counting whatever is in the deep interior. Further, some of that on the Moon will not be water in the sense we think of water. The neutron scattering picks out hydrogen, and that can also come from materials such as hydroxyapatite, which is present in some lunar rocks. The ice sits in cold traps; parts of the body where the temperature is always below -175 oC. For the Moon, there are (according to the article) about 26,000 km2 cold enough, while Mercury has only 7,000 km2. So, why is the Moon so dry?

Before going any further, it might help some understand what follows if they understand what isotopes are, and what effects they have. The nature of an element is defined by the number of electrons, which also equals the number of protons. For any given number of protons, there may be a variation in the number of neutrons. Thus all chlorine atoms (found in common salt) have 17 protons, and either 18 or 20 neutrons. The two different types of atoms are called isotopes. Of particular interest, hydrogen has two such isotopes: ordinary hydrogen and deuterium with 0 and 1 neutron respectively. This has two effects. The first is the heavier one usually boils or sublimes at a slightly higher temperature and in a gravitational field, is more likely to be at the top, hence ice that spends a lot of time in space tends to be richer in deuterium. The second effect is the chemical bond is stronger for the heavier isotope.

So where do volatiles (water and gases) on the rocky planets come from? I raised some of the issues on where it did not come from earlier: https://wordpress.com/post/ianmillerblog.wordpress.com/564 To summarize, the first option is the accretion disk. That is where Jupiter’s came from. If the body is big enough before the gases are removed, they will remain as an atmosphere. We can reject that. The planets will have had such atmospheres, but soon after formation of the star, it starts spitting out extreme UV/Xray radiation, and intense solar winds, and these strip the volatiles. The evidence that this removed most of the atmosphere from Earth is that some very heavy inert gases, such as krypton and xenon, have heavy isotope enhancements suggesting they have been fractionally distilled, and some of the heavier isotopes were enhanced. These gases are extremely rare, but they also cannot be accreted by any mechanism other than gravity and adsorption, and unless they were so stripped, there would be huge amounts of neon here because physical mechanisms of accretion apply equally to all the so-called rare gases, and neon is very abundant in the accretion disk. However the krypton was accreted, very large amounts of neon would also be accreted. Neon is rare, so most gases that arrived with the krypton would have been similarly removed. As would be water. So after a few hundred million years, the rocky planets were essentially rocks, with only very thin atmospheres. That, of course, is assuming our star behaved the same way as other similar stars, and that the effects of the high energy radiation are correctly assessed.

So, where did our atmosphere and oceans come from? There are only two possibilities: from above and from below. Above means comets and asteroid-type bodies colliding with Earth. Below means the elements were accreted with the solids, and emitted through volcanoes. Which one? This is where the Mercury/Moon data becomes significant. However, as often is the case, there is a catch. Mathematical modeling suggests that the Moon might have changed its obliquity, and once upon a time it was almost lying on its side. If so, and if this occurred for long enough, there would have been no permanently cold points, and the Moon would have lost its ice. It did not, but the questions then are, did this actually happen, did that period last long enough, or did the water arrive on the surface after this tilting?

Back to Earth’s atmosphere. The idea that Earth was struck by comets has been just about falsified. The problem lies in the fact that the comets have enriched deuterium, and there is too much for Earth’s water to have come from there, other than in minor amounts. A similar argument holds for chondrites. It is not the water that is the problem, but rather the solid rock. The isotope ratios of the chondrite rocks do not match Terran rocks. The same applies for the Moon, because the isotope ratios of the surface of the moon are essentially the same as on Earth, and the Moon has not has resurfacing. That essentially requires the water on Earth to have come from below, volcanically. I gave an account of that at https://wordpress.com/post/ianmillerblog.wordpress.com/576

And now we see why the extreme dryness of the Moon is so important: it shows that very little water did land on the Moon from comets and chondrites. Yes, that was shown from isotopes, but it is very desirable that all information is consistent. When you have a set of different sorts of information that lead to the same place, we can have more confidence in that place being right.

The reason why the Moon is so dry is now simple if we accept the usual explanation for how it was formed. The Moon formed from silicates blasted out of the Earth when Theia collided with it. Exactly where Theia came from is another issue, but the net result was a huge amount of silicates were thrown into orbit, and these stuck together to form the Moon. We now come to a problem that annoys me. I saw a review where it said these silicates were at a temperature approaching 1100 oC At that temperature, zinc oxide will start top boil off in a vacuum, and the lunar rocks are depleted in zinc. According to the review, published in October, it could not have been hotter because the Moon is not significantly depleted in potassium. However, in the latest edition of Nature (at the time of writing this) an article argued there was a depletion of potassium. Who is right, and how does whoever it is know? Potasium is a particularly bad element to choose because it separates out and gets concentrated in certain rocks, and we do not have that many samples. However, for water it is clear: the silicates were very hot, and the water was largely boiled off.

So, we have a conclusion. I suppose we cannot know for sure that it is absolutely right because we cannot know there is not some other theory that might explain these facts, but at least this explanation is consistent with what we know.

To conclude, some personal stuff. There will be no post from me next week; I am having hip replacement surgery. Hopefully, back again in a fortnight. Second, for those interested in my economic thoughts, my newest novel, ‘Bot War, will be available from December 2, but it is available for preorder soon.

More on theocracy

In the midst of all the ISIS stuff going on, I had to release my latest literary effort. In the event any of my readers have also read any of my other novels, you might have noticed that they portray a number of different forms of governance, and highlight the flaws in each. And no, I have not worked out what will work best, and maybe nothing will because as some of the books show, what goes wrong is because some of the characters put self-interest before the greater good. That is hardly original, of course, as was the basic reason the Res Publica failed. Anyway, the latest is the theocracy.

You may ask, how could an advanced civilization have theocracy? Well, in this story the planet around Epsilon Eridani was specifically engineered (and no, there is no evidence this planet exists) and seeded with late Cretaceous life that evolved into a civilization. Think about it; in the great debate relating evolution to creation, what would you think if there were no fossils at all prior to 65 My BP? And what is the difference between an advanced alien race of engineers that can operate over several hundred million years and a God? Anyway, the odd one of them ends up deciding that it would be desirable to remove mammals (us) from the planet of creation (Earth). The question is, how can such religious fervour be averted?

After all this thinking, can I suggest anything to apply to ISIS? The best I can come up with is that some Muslims have to overturn the Wahhabi doctrine and reform Islam. That is not exactly a highly probable outcome right now. Nevertheless, I think it is important. If all you do is bomb them, you probably create more angry recruits than you remove. The problem is, you remove infrastructure and kill the innocent as well as the guilty. And here, “innocent” is taken to mean anyone not actively going out there fighting for ISIS. (As usual, it is important to define terms, particularly if you use them in a slightly different way to others.) Even if ISIS were wiped out, what remains? I have seen one estimate that the cost of rebuilding Syria, which has had half its hospitals and about two million homes obliterated, is about $300 billion! And after you leave this mess behind, all the reasons and the Wahhabi philosophy remain, and if anything, are reinforced.

One other alternative is that of Titus Flavius Vespasianus: you start at one end of the country and kill everyone that is not clearly allied. I doubt modern society is ready for that solution. There are only two ways to win a war: remove the opposition from the field, or remove the will to fight. If you are not going to do the first, then you must concentrate on the second. Exactly how to do it remains a problem, but if someone can reform Islam, that would be a great start. The problem is, Islam does not have an official structure, so the only way to do that would appear to require someone with extreme charisma who will overturn wahhabiism. Do I hear a, “Good luck with that”?

Meanwhile, a quick commercial: Ranh, a tale of plotting, conspiracy, religious fervour, murder, treachery, honour, diplomacy, and tail-ball.

Respect for the top job?

Many of my scifi ebooks look at the question, how do people respond to the group, i.e. following fashion, or responding to conditions imposed by governments, or worse still, by religions? In the first novel of my “First Contact” trilogy, a party of five had found that aliens expected humanity to behave better before it thought about going to other star systems. In my second novel, Dreams Defiled, four of them set out to accomplish difficult tasks. The objective of two was to make things fairer for all citizens, of one to manage the greatest engineering feat of mankind, and of one to try to make the settlements on Mars more achievable. The fifth had only one dream: to be important, by any means possible.

The trilogy is really about for most the desire to comply with the group, for a few, the desire to be different, and for some, the desire to take advantage of everything they can, at the expense of all if necessary. The background is one of economic stagnation, where almost everyone works in a corporation because there are very few resources available for the general population, and because it is the political fashion to do so. There are those who do not, and the majority react badly to them. The story revolves about people who have great ability, but who will be subverted by lesser people, and also of how corruption and lack of attention to maintaining solid moral and ethical values amplifies the evil in weak people. Part of the story involves the tendency of the group of people to pick on those who are not part of the group fashion, and those who would betray anyone for money. Also, the story required the most evil person I could manage to create for the third book in the trilogy.

When I published this, it was with a little tongue in cheek. The mindlessness could not happen. If people stepped too far out of line, public opinion would bring them back into line. There is nothing wrong with opposing government actions, and indeed countries following the British parliamentary system have what is called “the loyal opposition”. The idea is, those who lost the last election have the task of keeping the winners honest, and producing arguments to show the flaws in the policies of the winners. It may not always end up quite so “pure”, but in general, that is supposedly what they do. But surely deliberate subversion is out? We may not agree with the top men (or women) but surely we accept they are there.

Unfortunately, it seems to happen, albeit on a much smaller scale. Recall the birthing issue with President Obama? Let us suppose this was truly an issue, what is the correct way to go about dealing with it? In my opinion, simply provide evidence that there was a problem. Fair enough to raise the issue, but without evidence, it cannot go further. And surely, there would be many others who had looked at this first. Then look at President Obama’s record, including what seems to be referred to as Obamacare. This was a policy announced as a candidate, so when he won the election, surely he was required to carry out such a policy. The people had voted for him, hence they voted for his announced policy. Is that not what the electoral system is supposed to mean? Should not those who lose accept it, at least until the next election?

The real question may be, why does the man at the top polarize opinion so much? Is it because we place too much emphasis on the person at the top? In business, do you really think the man at the top actually does what makes the business work? Or is it all the underlings? While there is the occasional great person at the top, most of the leaders I have met are depressingly ordinary, and have got there largely because they have one big ability: the ability to gest to the top.

The theme, if you like, is the place of the individual with respect to the greater group. Everyone cannot be President, which raises the question, why is doing the best you can be a lesser role? Perhaps one of the most admirable examples was that of Marcus Vipsanius Agrippa. Without Agrippa, Augustus would have been nothing, because Agrippa was the man who won his battles, and he was the person who got things done. When another aqueduct was needed, Agrippa arranged for its construction. And Agrippa was always in the background, leaving Augustus to take the credit. The point is, this did not matter to Agrippa. Governments need more people like this.

Why raise this now? Dreams Defiled will be on an Amazon countdown discount as from September 11, so now seemed to be the time ☺

An “invention” in Science Fiction, or reinventing the wheel!

One thing expected of science fiction authors is they should “invent” something, although obviously only in fiction. Remember the Star Trek “communicator”, which now is recognizable as a flip-open cell phone. In other words, Star Trek anticipated it. How? Well, obviously, as with other real inventions, there was a need. People exploring need to communicate with others, so they had a communicator. Obviously, you want it to be small and convenient, so it was small and convenient.

So, what has this got to do with me? Well, in my novels about the colonization of Mars, there were obvious things that had to be done, and one of these was I thought it desirable to have some sort of plant that would live outside of specialized domes. The reason for this is that people badly need the products of plants, and it would be really helpful if you could grow something out in the wastes. This led to the need to “invent” a plant that could grow outside, and hence the genetic engineers developed the “Mars cactus”. So what would it look like?

One thing that a Mars cactus would not need is spikes. No need to defend against plant eaters because there aren’t any. Obviously it had to defend itself against the bitter cold of night, so what I envisaged was a thick-skinned plant that was more like a “flat rock”, and was very thick. Inside, it had antifreeze. It would still need water, so to start with, some form of watering had to be carried out, and more on that in a later post. The next thing it needed was protection against the UV light, and it needed to absorb heat, and fortunately both of these could be achieved with a dark absorber. Many plants on earth actually have UV absorbers. Also, it had to make something useful, but fortunately it is not that difficult to envisage a plant containing cellulose.

However, the really big problem is any plant growing outside has to be able to reproduce to be useful, so I envisaged what I thought was a sneaky strategy, based a little on my experience with seaweeds. Seaweeds have an interesting sex life. They have male and female forms, and these reproduce if they can be close enough together to fertilize each other. Seaweeds, of course, have the advantage that the water currents may et the gametes get together. The offspring of such fertilization are sporophytes, which do not need fertilizing and they send out clouds of spores that if they take hold of anything, they grow into the male and female forms.

So, my Mars cactus had the following reproductive strategy. It grew tendrils underground, and if these touched a tendril of the opposite sex, an entity grew that would reach up and grow on the surface and when mature would send out clouds of spores. The spores would settle, dig into the ground, and form the tendril form. Does that seem plausible? You may think that is ridiculous, but, as I found out later, it is quite plausible. It is, after all, the reproductive strategy of the mushroom, and mushrooms, and other fungi, have existed for a very very long time. Not reinventing the wheel, perhaps, but reinventing the fungus.