Liquid Fuels from Algae

In the previous post, I discussed biofuels in general. Now I shall get more specific, with one particular source that I have worked on. That is attempting to make liquid fuels from macro and microalgae. I was recently sent the following link:

https://www.fool.com/investing/2017/06/25/exxonmobil-to-climate-change-activists-chew-on-thi.aspx

In this, it was reported that ExxonMobil partnering Synthetic Genomics Inc. have a $600 million collaboration to develop biofuels from microalgae. I think this was sent to make me green with envy, because I was steering the research efforts of a company in New Zealand trying to do the same, except that they had only about $4 million. I rather fancy we had found the way to go with this, albeit with a lot more work to do, but the company foundered when it had to refinance. It could have done this in June 2008, but it put it off until 2009. I think it was in August that Lehmans did a nosedive, and the financial genii of Wall Street managed to find the optimal way to dislocate the world economies without themselves going to jail or, for that matter, becoming poor; it was the lesser souls that paid the price.

The background: microalgae are unique among plants in that they devote most of their photochemical energy into either making protein and lipids, which in more common language are oily fats. If for some reason, such as a shortage of nitrogen, they will swell up and just make lipids, and about 75 – 80% of their mass are comprised of these, and when nitrogen starved, they can reach about 70% lipids before they die of starvation. When nitrogen is plentiful, they try to reproduce as fast as they can, and that is rapid. Algae are the fastest growing plants on the planet. One problem with microalgae: they are very small, and hence difficult to harvest.

So what is ExxonMobil doing? According to this article they have trawled the world looking for samples of microalgae that give high yields of oil. They have tried gene-editing techniques to grow a strain that will double oil production without affecting growth rate, and they grow these in special tubes. To be relevant, they need a lot of tubes. According to the article, if they try open tanks, they need an area about the size of Colorado to supply America’s oil demand, and a corresponding lot of water. So, what is wrong here? In my opinion, just about everything.

First, you want to increase the oil yield? Take the microalgae from the rapidly growing stage and grow them in nitrogen-starved conditions. No need for special genetics. Second, if you are going to grow your microalgae in open tanks (to let in the necessary carbon dioxide and reduce containment costs) you also let in airborne algae. Eventually, they will take over because evolution has made them more competitive than your engineered strain. Third, no need to consider producing all of America’s liquid fuels all at once; electricity will take up some, and in any case, there is no single fix. We need what we can get. Fourth, if you want area, where is the greatest area with sufficient water? Anyone vote for the ocean? It is also possible that microalgae may not be the only option, because if you use the sea, you could try macroalgae, some of which such as Macrocystis pyrifera grow almost as fast, although they do not make significant levels of lipids.

We do not know how ExxonMobil intended to process their algae. What many people advocate is to extract out the lipids and convert them to biodiesel by reacting them with something like sodium methoxide. To stop horrible emulsions while extracting, the microalgae need to be dried, and that uses energy. My approach was to use simple high pressure processing in water, hence no need to dry the algae, from which both a high-octane petrol fraction and a high-cetane diesel fraction could be obtained. Conversion efficiencies are good, but there are many other byproducts, and some of the residue is very tarry.

After asking where the best supply of microalgae could be found, we came up with sewage treatment ponds. No capital requirement for building the ponds, and the microalgae are already there. In the nutrient rich water, they grow like mad, and take up the nutrients that would otherwise be considered pollutants like sponges. The lipid level by simple extraction is depressingly low, but the levels that are bound elsewhere in the algae are higher. There is then the question of costs. The big cost is in harvesting the microalgae, which is why macroalgae would be a better bet in the oceans.

The value of the high pressure processing (an accelerated treatment that mimics how nature made our crude oil in the first place) is now apparent: while the bulk of the material is not necessarily a fuel, the value of the “byproducts” of your fuel process vastly exceeds the value of the fuel. It is far easier to make money while still working on the smaller scale. (The chemical industry is very scale dependent. The cost of making something is such that if you construct a similar processing plant that doubles production, the unit cost of the larger plant is about 60% that of the smaller plant.)

So the approach I favour involves taking mainly algal biomass, including some microalgae from the ocean (and containing that might be a problem) and aiming initially to make most of your money from the chemical outputs. One of the ones I like a lot is a suite of compounds with low antibacterial activity, which should be good for feeding chickens and such, which in turn would remove the breeding ground for antibiotic resistant superbugs. There are plenty of opportunities, but unfortunately, a lot of effort and money required it make it work.

For more information on biofuels, my ebook, Biofuels An Overview is available at Smashwords through July for $0.99. Coupon code NY22C

Reducing Greenhouse Gas Emissions

Leaving aside the obstinate few, the world is now coming to realize that our activities are irreversibly changing the climate through sending so-called greenhouse gases into the atmosphere. Finally a number of politicians (but not President Trump) have decided they have to do something about it. Economists argue the answer lies in taxes on emissions, but that will presumably only work if there are alternative sources of energy that do not cause an increase in emissions. The question is, what can be done?

The first thing to note is the climate is significantly out of equilibrium, that is to say, the effects have yet to catch up with the cause. The reason is, while there is a serious net power input to the oceans, much of that heat is being dissipated by melting polar ice. Once that melting process runs its course, there will be serious temperature rises, and before that, serious sea level rises. My point is, the net power input will continue long after we stop emitting greenhouse gases altogether, and as yet we are not seeing the real effects. So, what can we do about the gases already there? The simplest answer to that is to grow lots and lots of forests. There is a lot of land on the planet that has been deforested, and merely replacing that will pull CO2 out of the air. The problem then is, how do we encourage large-scale tree planting when economics seems to have led to forests being simply cut and burned? In principle, forest owners could get credits through an emissions trading scheme, but eventually we want to encourage this without letting emitters off the hook.

Now, suppose we want to reduce our current rate of emissions to effectively zero, what are the difficulties? There are five major sources that will be difficult to deal with. The first is heating. Up to a point, this can be supplied by electricity, including the use of heat pumps, but that would require a massive increase in electrical supply, and an early objective should be to close down coal-fired electricity generators. We can increase solar and wind generators, but note that there will be a large increase in emissions to make the construction materials, and there is a question as to how much they can really produce. Of course, every bit helps.

The second involves basic industrial materials, which includes metal smelting, cement manufacture, and some other processes where high temperatures and chemical reduction are required. In principle, charcoal could replace coal, if we grew enough forests, but this is difficult to really replace coal.

The third includes the gases in a number of appliances or from manufacturing processes. The freons in refrigerators, and some gases used in industrial processes are serious contributors. There may not be so much of them as there is of carbon dioxide, but some are over ten thousand times more powerful than carbon dioxide, and there is no easy way for the atmosphere to get rid of them. Worse, in some cases there are no simple alternatives.

The fourth is agriculture. Dairy farming is notorious for emitting methane, a gas about thirty-five times stronger than carbon dioxide, although fortunately its lifetime is not long, and nitrous oxide from the effluent. Being vegetarian does not help. Rice paddies are strong emitters, as is the use of nitrogen fertilizer, thus ammonium nitrate decomposes to nitrous oxide. Nitrous oxide is also more powerful and longer lived than carbon dioxide.

The fifth is, of course, transport. In some ways transport is the easiest to deal with, but there are severe difficulties. The obvious way is to use electric power, and this is obviously great for electrified railways but it is less satisfactory without direct contact with a mains power supply. Battery powered cars will work well for personal transport around cities, but the range is more questionable. Apparently rapid charge batteries are being developed, where a recharge will take a bit over a quarter hour, although there is a further issue relating to the number of charging points. If you look at many main highways and count the number of vehicles, how would you supply sufficient charging outlets? The recharge in fifteen minutes is no advantage if you have to wait a couple of hours to get at a power point. Other potential problems include battery lifetime. As a general rule, the faster you recharge, the fewer recharges the battery will take. (No such batteries last indefinitely; every recharge takes something from them, irreversibly.) But the biggest problem is power density. If you look at the heavy machinery used in major civil engineering projects, or even combine harvesters in agriculture, you will see that diesel has a great advantage. Similarly with aircraft. You may be able to fly around the world in a battery/solar-powered craft, but that is just a stunt, as the aircraft will never be much better than a glider.

One answer to the power density problem is biofuels. There are a number of issues relating to them, some of which I shall put in a future post. I have worked in this field for much of my career, and I have summarized my thoughts in an ebook “Biofuels”, which over the month of July will be available at $1 at Smashwords. The overall message relating to emissions, though, is there is no magic bullet. It really is a case of “every bit helps”.

The Grenfell Fire, and the Logic of Plastics in Cladding

For me, the most depressing recent news was the London fire, in which a high-rise of flats (apartments for Americans) somehow caught fire, and once it did, it spread like crazy. There is a lot of blame to share around for the death toll. Apparently people were told to stay in their flats, but that advice was given by firemen who were unaware that the building had no useful fire doors, or the other usual means of containing and retarding fires. After all, if the building is concrete, and there is no easy way to spread the fire, it should be able to be kept local. So what went wrong? We don’t know about why the interior of the building seemed to burn very nicely, but it seemed that the outside burned furiously. The outside had an aluminium cladding, apparently to make it look more attractive. The aluminium tiles were backed by polyethylene, which is essentially a solid hydrocarbon of structure similar to diesel, but a much larger molecular weight. That burns very well, and if you saw video of it, you would see great globs of fire falling off the building.

We don’t know exactly why the polyethylene was there. Some say heat insulation, others say to give the cladding rigidity. Much has also been made of the fact that for about $3 a tile more, the backing could have been fire resistant. I am not sure what that backing is as the maker’s website does not say, but would guess it is some sort of polyamide or polyurethane with non-flammable filler. These certainly do not catch fire as easily, but there is another catch with some of them: in a fire they do burn, and while not as well, they tend to give off some rather poisonous gases. There is another catch. According to the manufacturer, the fire resistant tiles passed ASTM E 84 tests, which are the standard tests for surface burning characteristics, but so did the polyethylene backed tiles. That sort of lab test does not represent a real fire.

This brought back memories of my past, when I got involved with two structural foams that could be suitable for building cladding. One was a glass foam, originally intended to be made from waste glass. This would make quite a good wall cladding without the aluminium, except possibly on the bottom floor because it does not have very good impact resistance. Thin glass shatters on impact, but it does not burn or corrode. You can also have a wide range of colours. The other is a plastic foam, for which you do not even need fillers to make it fire resistant.

The story of my involvement with that goes back to the late 1970s. In the late 1960s, New Zealand discovered a large offshore natural gas field, and the government took it upon itself to enter a “take or pay” agreement so the field would be developed. It was not clear what their idea was, but presumably electricity generation was one of them. However, when the first energy crisis struck, about 1972 from memory, there was a sort of panic, and after a lot of deliberation they decided to construct a synthetic fuels plant at Motunui, which was to use a process developed by Mobil. I was on a committee to advise on the science, and I advised this was a bad idea because they could not build it for anything like the costs presented to them. As it turned out, my projected cost was out by $200 million, but no site had been chosen, and my estimate was “plus site development”. (In the end, the site development would have been about $130 million, so I was rather pleased with myself.) However, at the committee, I was about 4.5 times greater than the figure they were comfortable with (and note the government was going to pay) so I was never asked to be on such committees again. However, when that process was chosen, I knew that there was one byproduct they would not know what to do with: 1,2,4,5-tetramethylbenzene. The reason: it is a solid, which is not good in petrol for cars. The good news from my point of view was that it could be oxidized to pyromellitic dianhydride, which would be a precursor to stepladder and even ladder polymers, and in particular to polyimide plastics. The bad news was that the top public servants did not want their synfuels project upstaged, and the politicians were unenthused, probably because they were totally out of their depth.

So to get rid of the road blocks, I needed a stunt. As it happened, the fire hazard with plastic foams was to be the subject of a half-hour nationwide TV program, and I was invited to comment as a scientist. I agreed, provided I could have a few minutes for a demonstration of fire resistant foams. That was agreed, so I made myself some polyimide foam. This was rigid, and not much use for furniture, but you can’t really do much development work with one day’s notice. So I turned up, and at the end of the program, which had the dangers of fires, and of the poisonous gases drilled into everyone, I had the cameras turned on me. I put a bit of home-made foam in the palm of my hand and directed a gas torch at it. It glowed a nice yellow-hot under the flames, and I just sat there. Eventually they got bored of watching this, and they turned off the torch, then made the comment, “It still stinks, though.” So, with a bit of acting here, I held the plastic up to my face and sniffed deeply, and made no expression. Since there was no fire, while the plastic was ablating slowly, once the torch was taken away there was no more reaction. Unfortunately, my wife forgot to record this so I can’t actually prove it.

The whole point of this, of course, is it is possible to make very fire resistant foams. Without the type of chemical plant I was proposing, such foams would be expensive, but the question then is, is preventing x number of deaths worth spending a few extra dollars (or in this case, pounds)? In my opinion, there is no real excuse. Yes, the foam I made was rigid, but as building insulation, so what? While science can provide answers to many problems, there is not much point in it if nobody in power takes any notice.

UK Election Fallout and Qatar: what would you do if in charge?

Suppose like me you are an author of fiction. Given the following situations, put yourself in someone’s shoes and ask yourself, what next?

The first event was the rather unfortunate end result of the UK election. What was delivered was what I consider to be the worst possible outcome. The problem is, voters are sucked in by “jam today”, or “I am annoyed about something.” So, what now? First, some background. The national debt of Britain now stands at £ 1.73 trillion, and the interest payment on this debt is about 6% of revenue. That might seem to be reasonably sustainable, but there is the overall issue of Brexit looming. The UK has apparently had a recent surge in GDP, despite the threat of Brexit, but it is not clear that will last, and interest rates will probably grow from their record low. Suppose they double, which is easy from such lows. 6% suddenly turns to 12%, and that is ugly. (The existing loans will stay at their agreed rate, but can you pay them back when they mature? Otherwise you have to borrow at the new rate.) It appears that Jeremy Corbyn was promising a lot of spending, together with an unspecified increase in taxes. My guess is a lot of the youth vote that went to Corbyn thought the rich would pay. The usual problem with that assessment is that while the rich can be made to pay significantly higher taxes, to get the amounts needed to make a significant difference in revenue tax rises have to go a lot deeper. There are just not enough rich to soak. On the other hand, people may well argue they needed more money to go to health, education, or whatever. The question then is, can you pay for what you want?

May was apparently promising austerity. That is hardly attractive, but it was also put forward in a rather clumsy way. Cutting out school lunches is not only hardly a vote winner, but it is also never going to make a huge difference. Putting that up front is a strange way to win an election. It seems that the Tories were so convinced they were going to win that they decided to put up some policies that they knew would be unpopular, so they could say later, “You voted for them.” The two who are believed to have largely written the manifesto have resigned (really, pushed by angry senior Tories) but the question remains, why were they left to write it? Why did the senior Cabinet Ministers not know what was in it, or if they knew, why did they not do something about it? There’s plenty of blame to go around here, folks, nevertheless there are two hard facts: if Britain and the EU cannot manage Brexit properly, there will be severe economic problems, and economic problems seem to be like a very active virus that goes everywhere very quickly. The second is, if debt gets out of hand, the country spends so much on interest repayments that it ends up in the position Greece is now in. Anyone want that?

So, put yourself in some position: what would you do? My opinion is the Tories should realize that Corbyn has no chance currently of forming a government (because he needs every non-Tory vote) and get on doing something that has at least some public appeal. May either has to go, or learn oratory and get some empathy for the others.

The other event is the Arab attempt at isolating Qatar, on the grounds it is financing terrorism. Actually, the Saudis are almost certainly the biggest such supporters. The real reason appears to be either Qatar is friendly with Iran, or alternatively Qatar is the home of al Jazeera, a TV network that tries by and large to report the facts, warts and all. The US position on this is obscure. President Trump has lashed out against Qatar, without any particular evidence, although Qatar is known to have given refuge a number of Egypt’s Muslim Brotherhood. The US is also bombing Assad’s troops in Syria to prevent them getting at fleeing ISIS fighters; it seems that terrorism is being actively supported by the US, which make no strategic sense. At first, it looks as if Qatar could be quickly invaded from Saudi Arabia, but whoever does that would have to be very careful because Qatar houses the biggest local US base in the region, and has 11,000 military personnel there. To add to the complications, Turkey has promised to send troops. Fighting Turkey should mean fighting NATO, although with President Trump nothing automatically follows.

So, imagine you are the leader of Qatar, what would you do? Return the Muslim Brotherhood members to Egypt where they would probably be tortured and/or executed? Promise to stop funding terrorists? (If you really are not, this is easy to keep, but maybe not so easy to convince others that you are keeping it.) Remember, whatever you decide to do, you have to be prepared for whatever consequences follow. Not easy working out what leaders should do, is it? Writing fiction is, of course, easier, because you control what happens next. But if you want that fiction to have some relation with reality, what happens next has to be plausible, so here is your chance to get some practice.

Star and Planetary Formation: Where and When?

Two posts ago, as a result of questions, I promised to write a post outlining the concept of planetary accretion, based on the current evidence. Before starting that, I should explain something about the terms used. When I say something is observed, I do not mean necessarily with direct eyesight. The large telescopes record the light signals electronically, similarly to how a digital camera works. An observation in physics means that a signal is received that can be interpreted in one only certain way, assuming the laws of physics hold. Thus in the famous two-slit experiment, if you fire one electron through the slits, you get one point impact, which is of too low an energy for the human eye to see. Photomultipliers, however, can record this as a pixel. We have to assume that the “observer” uses laws of physics competently.

The accretion of a star almost certainly starts with the collapse of a cloud of gas. What starts that is unknown, but it is probably some sort of shock wave, such as a cloud of debris from a nearby supernova. Another cause appears to be the collision of galaxies, since we can see the remains of such collisions that are accompanied by a large number of new stars forming. The gas then collapses and forms an accretion disk, and these have been observed many times. The gas has a centre of mass, and this acts as the centre of a gravitational field, and as such, the gas tries to circulate at an orbital velocity, which is where the rate of falling into the star is countered by the material moving sideways, at a rate that takes it away from the star so that the distance from the centre remains the same. If they do this, angular momentum is also conserved, which is a fundamental requirement of physics. (Conservation of angular momentum is why the ice skater spins slowly with arms outstretched; when she tucks her arms in, she spins faster.

The closer to the centre, the strnger gravity requires faster orbital velocity. Thus a stream of gas is moving faster than the stream just further from the centre, and slower than the stream just closer. That leads to turbulence and friction. Friction slows the gas, meaning it starts to fall starwards, while the friction converts kinetic energy to heat. Thus gas drifts towards the centre, getting hotter and hotter, where it forms a star. This has been observed many times, and the rate of stellar accretion is such that a star takes about a million years to form. When it has finished growing, there remains a dust-filled gas cloud of much lower gas density around it that is circulating in roughly orbital velocities. Gas still falls into the star, but the rate of gas falling into the star is at least a thousand times less than during primary stellar accretion. This stage lasts between 1 to 30 million years, at which point the star sends out extreme solar winds, which blow the gas and dust away.

However, the new star cannot spin fast enough to conserve angular momentum. The usual explanation is that gas is thrown out from near the centre, and there is evidence in favour of this in that comets appear to have small grains of silicates that could only be formed in very hot regions. The stellar outburst noted above will also take away some of the star’s angular momentum. However, in our system, the bulk of the angular momentum actually resides in the planets, while the bulk of the mass is in the star. It would seem that somehow, some angular momentum must have been transferred from the gas to the planets.

Planets are usually considered to form by what is called oligarchic growth, which occurs after primary stellar accretion. This involves the dust aggregating into lumps that stick together by some undisclosed mechanism, to make first, stone-sized objects, then these collide to form larger masses, until eventually you get planetesimals (asteroid-sized objects) that are spread throughout the solar system. These then collide to form larger bodies, and so on, at each stage collisions getting bigger until eventually Mars-sized bodies collide to form planets. If the planet gets big enough, it then starts accreting gas from the disk, and provided the heat can be taken away, if left long enough you get a gas giant.

In my opinion, there are a number of things wrong with this. The first is, the angular momentum of the planets should correspond roughly to the angular momentum of the dust, which had velocity of the gas around it, but there is at least a hundred thousand times more gas than dust, so why did the planets end up with so much more angular momentum than the star? Then there is timing. Calculations indicate that to get the core of Jupiter, it would take something approaching 10 million years, and that assumes a fairly generous amount of solids, bearing in mind the solid to gas ratio. At that point, it probably accretes gas very quickly. Get twice as far away from the star, and collisions are much slower. Now obviously this depends on how many planetesimals there are, but on any reasonable estimate, something like Neptune should not have formed. Within current theory, this is answered by having Neptune and Uranus being formed somewhere near Saturn, and then moved out. To do that, while conserving angular momentum, they had to throw similar masses back towards the star. I suppose it is possible, but where are the signs of the residues? Further, if every planet is made from the same material, the same sort of planet should have the same composition, but they don’t. The Neptune is about the same size as Uranus, but it is about 70% denser. Of the rocky planets, Earth alone has massive granitic/feldsic continents.

Stronger evidence comes from the star called LkCa 15 that apparently has a gas giant forming that is already about five times bigger than Jupiter and about three times further away. The star is only 3 million years old. There is no time for that to have formed by this current theory, particularly since any solid body forming during the primary stellar accretion is supposed to be swept into the star very quickly.

Is there any way around this? In my opinion, yes. I shall put up my answer in a later post, although for those who cannot wait, it is there in my ebook, “Planetary Formation and Biogenesis”.

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.

Martian Fluvial Flows, Placid and Catastrophic

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Despite the fact that, apart localized dust surfaces in summer, the surface of Mars has had average temperatures that never exceeded about minus 50 degrees C over its lifetime, it also has had some quite unexpected fluid systems. One of the longest river systems starts in several places at approximately 60 degrees south in the highlands, nominally one of the coldest spots on Mars, and drains into Argyre, thence to the Holden and Ladon Valles, then stops and apparently dropped massive amounts of ice in the Margaritifer Valles, which are at considerably lower altitude and just north of the equator. Why does a river start at one of the coldest places on Mars, and freeze out at one of the warmest? There is evidence of ice having been in the fluid, which means the fluid must have been water. (Water is extremely unusual in that the solid, ice, floats in the liquid.) These fluid systems flowed, although not necessarily continuously, for a period of about 300 million years, then stopped entirely, although there are other regions where fluid flows probably occurred later. To the northeast of Hellas (the deepest impact crater on Mars) the Dao and Harmakhis Valles change from prominent and sharp channels to diminished and muted flows at –5.8 k altitude that resemble terrestrial marine channels beyond river mouths.

So, how did the water melt? For the Dao and Harmakhis, the Hadriaca Patera (volcano) was active at the time, so some volcanic heat was probably available, but that would not apply to the systems starting in the southern highlands.

After a prolonged period in which nothing much happened, there were catastrophic flows that continued for up to 2000 km forming channels up to 200 km wide, which would require flows of approximately 100,000,000 cubic meters/sec. For most of those flows, there is no obvious source of heat. Only ice could provide the volume, but how could so much ice melt with no significant heat source, be held without re-freezing, then be released suddenly and explosively? There is no sign of significant volcanic activity, although minor activity would not be seen. Where would the water come from? Many of the catastrophic flows start from the Margaritifer Chaos, so the source of the water could reasonably be the earlier river flows.

There was plenty of volcanic activity about four billion years ago. Water and gases would be thrown into the atmosphere, and the water would ice/snow out predominantly in the coldest regions. That gets water to the southern highlands, and to the highlands east of Hellas. There may also be geologic deposits of water. The key now is the atmosphere. What was it? Most people say it was carbon dioxide and water, because that is what modern volcanoes on Earth give off, but the mechanism I suggested in my “Planetary Formation and Biogenesis” was the gases originally would be reduced, that is mainly methane and ammonia. The methane would provide some sort of greenhouse effect, but ammonia on contact with ice at minus 80 degrees C or above, dissolves in the ice and makes an ammonia/water solution. This, I propose, was the fluid. As the fluid goes north, winds and warmer temperatures would drive off some of the ammonia so oddly enough, as the fluid gets warmer, ice starts to freeze. Ammonia in the air will go and melt more snow. (This is not all that happens, but it should happen.)  Eventually, the ammonia has gone, and the water sinks into the ground where it freezes out into a massive buried ice sheet.

If so, we can now see where the catastrophic flows come from. We have the ice deposits where required. We now require at least fumaroles to be generated underneath the ice. The Margaritifer Chaos is within plausible distance of major volcanism, and of tectonic activity (near the mouth of the Valles Marineris system). Now, let us suppose the gases emerge. Methane immediately forms clathrates with the ice (enters the ice structure and sits there), because of the pressure. The ammonia dissolves ice and forms a small puddle below. This keeps going over time, but as it does, the amount of water increases and the amount of ice decreases. Eventually, there comes a point where there is insufficient ice to hold the methane, and pressure builds up until the whole system ruptures and the mass of fluid pours out. With the pressure gone, the remaining ice clathrates start breaking up explosively. Erosion is caused not only by the fluid, but by exploding ice.

The point then is, is there any evidence for this? The answer is, so far, no. However, if this mechanism is correct, there is more to the story. The methane will be oxidised in the atmosphere to carbon dioxide by solar radiation and water. Ammonia and carbon dioxide will combine and form ammonium carbonate, then urea. So if this is true, we expect to find buried where there had been water, deposits of urea, or whatever it converted to over three billion years. (Very slow chemical reactions are essentially unknown – chemists do not have the patience to do experiments over millions of years, let alone billions!) There is one further possibility. Certain metal ions complex with ammonia to form ammines, which dissolve in water or ammonia fluid. These would sink underground, and if the metal ions were there, so might be the remains of the ammines now. So we have to go to Mars and dig.