Have you got what it takes to form a scientific theory?

Making a scientific theory is actually more difficult than you might think. The first step involves surveying what knowledge is already available. That comes in two subsets: the actual observational data and the interpretation of what everyone thinks that set of data means. I happen to think that set theory is a great start here. A set is a collection of data with something in common, together with the rule that suggests it should be put into one set, as opposed to several. That rule must arise naturally from any theory, so as you form a rule, you are well on your way to forming a theory. The next part is probably the hardest: you have to decide what interpretation that is allegedly established is in fact wrong. It is not that easy to say that the authority is wrong, and your idea is right, but you have to do that, and at the same time know that your version is in accord with all observational data and takes you somewhere else. Why I am going on about this now is I have written two novels that set a problem: how could you prove the Earth goes around the sun if you were an ancient Roman? This is a challenge if you want to test yourself as a theoretician. If you don’t. I like to think there is still an interesting story there.

From September 13 – 20, my novel Athene’s Prophecy will be discounted in the US and UK, and this blog will give some background information to make the reading easier as regards the actual story not regarding this problem. In this, my fictional character, Gaius Claudius Scaevola is on a quest, but he must also survive the imperium of a certain Gaius Julius Caesar, aka Caligulae, who suffered from “fake news”, and a bad subsequent press. First the nickname: no Roman would call him Caligula because even his worst enemies would recognize he had two feet, and his father could easily afford two bootlets. Romans had a number of names, but they tended to be similar. Take Gaius Julius Caesar. There were many of them, including the father, grandfather, great grandfather etc. of the one you recognize. Caligulae was also Gaius Julius Caesar. Gaius is a praenomen, like John. Unfortunately, there were not a lot of such names so there are many called Gaius. Julius is the ancient family name, but it is more like a clan, and eventually there needed to be more, so most of the popular clans had a cognomen. This tended to be anything but grandiose. Thus for Marcus Tullius Cicero, Cicero means chickpea. Scaevola means “lefty”. It is less clear what Caesar means because in Latin the “ar” ending is somewhat unusual. Gaius Plinius Secundus interpreted it as coming from caesaries, which means “hairy”. Ironically, the most famous Julius Caesar was bald. Incidentally, in pronunciation, the latin “C” is the equivalent of the Greek gamma, so it is pronounced as a “G” or “K” – the difference is small and we have now way of knowing. “ae” is pronounced as in “pie”. So Caesar is pronounced something like the German Kaiser.

Caligulae is widely regarded as a tyrant of the worst kind, but during his imperium he was only personally responsible for thirteen executions, and he had three failed coup attempts on his life, the leaders of which contributed to that thirteen. That does not sound excessively tyrannical. However, he did have the bad habit of making outrageous comments (this is prior to a certain President tweeting, but there are strange similarities). He made his horse a senator. That was not mad; it was a clear insult to the senators.

He is accused of making a fatuous invasion of Germany. Actually, the evidence is he got two rebellious legions to build bridges over the Rhine, go over, set up camp, dig lots of earthworks, march around and return. This is actually a text-book account of imposing discipline and carrying out an exercise, following the methods of his brother-in-law Gnaeus Domitius Corbulo, one of the stronger Roman Generals on discipline. He then took these same two legions and ordered them to invade Britain. The men refused to board what are sometimes called decrepit ships. Whatever, Caligulae gave them the choices between “conquering Neptune” and collecting a mass of sea shells, invading Britain, or face decimation. They collected sea shells. The exercise was not madness: it was a total humiliation for the two legions to have to carry these through Rome in the form of a “triumph”. This rather odd behaviour ended legionary rebellion, but it did not stop the coups. The odd behaviour and the fact he despised many senators inevitably led to bad press because it was the senatorial class that wrote histories, but like a certain president, he seemed to go out of his way to encourage the bad press. However, he was not seen as a tyrant by the masses. When he died the masses gave a genuine outpouring of anger at those who killed him. Like the more famous Gaius Julius Caesar, Caligulae had great support from the masses, but not from the senators. I have collected many of his most notorious acts, and one of the most bizarre political incidents I have heard of is quoted in the novel more or less as reported by Philo of Alexandria, with only minor changes for style consistency, and, of course, to report it in English.

As for showing how scientific theory can be developed, in TV shows you find scientists sitting down doing very difficult mathematics, and while that may be needed when theory is applied, all major theories start with relatively simple concepts. If we take quantum mechanics as an example of a reasonably difficult piece of theoretical physics, thus to get to the famous Schrödinger equation, start with the Hamilton-Jacobi equation from classical physics. Now the mathematician Hamilton had already shown you can manipulated that into a wave-like equation, but that went nowhere useful. However, the French physicist de Broglie had argued that there was real wave-like behaviour, and he came up with an equation in which the classical action (momentum times distance in this case) for a wave length was constant, specifically in units of h (Planck’s quantum of action). All that Schrödinger had to do was to manipulate Hamilton’s waves and ensure that the action came in units of h per wavelength. That may seem easy, but everything was present for some time before Schrödinger put that together. Coming up with an original concept is not at all easy.

Anyway, in the novel, Scaevola has to prove the Earth goes around the sun, with what was available then. (No telescopes that helped Galileo.) The novel gives you the material avaiable, including the theory and measurements of Aristarchus. See if you can do it. You, at least, have the advantage you know it does. (And no, you do not have to invent calculus or Newtonian mechanics.)

The above is, of course, merely the background. The main part of the story involves life in Egypt, the aanti-Jewish riots in Egypt, then the religious problems of Judea as Christianty starts.

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Monarchic Growth of Giant Planets

In the previous post, I outlined the basic mechanism of how I thought the giant planets formed, and how their mechanism of formation put them at certain distances from the sun. Given that, like everyone else, I assign Jupiter to the snow point, in which case the other planets are where they ought to be. But that raises the question, why one planet in a zone? Let’s take a closer look at this mechanism.

In the standard mechanism, dust accretes into objects by some unknown mechanism, and does this essentially based on collision probability, and so the disk progresses with a distribution of roughly equal sized objects that collide under the same rules, and eventually become what is called planetesimals, which are about the size of the classical asteroid. (I say classical because as we get better at this, we are discovering a huge number of much smaller “asteroids”, and we have the problem of what does the word asteroid mean?) This process continues, and eventually we get Mars-sized objects called oligarchs, or embryos, then these collide to get planets. The size of the planet depends on how many oligarchs collide, thus fewer collided to make Venus than Earth, and Mars is just one oligarch. I believe this is wrong for four reasons: the first is, giants cannot grow fast enough; second, the dust is still there in 30 My old disks; the collision energies should break up the bodies at any given size because collisions form craters, not hills; the system should be totally mixed up, but isotope evidence shows that bodies seem to have accreted solely from the material at roughly their own distance from the sun.

There is an alternative called monarchic growth, in which, if one body can get a hundred times bigger than any of the others, it alone grows by devouring the others. For this to work, we need initial accretion to be possible, but not extremely probable from dust collisions. Given that we see disks by their dust that are estimated to be up to 30 My old, that seems a reasonable condition. Then, once it starts, we need a mechanism that makes further accretion inevitable, that is, when dust collides, it sticks. The mechanism I consider to be most likely (caveat – I developed it so I am biased) is as follows.

As dust comes into an appropriate temperature zone, then collisions transfer their kinetic energy into heat that melts an ice at the point of contact, and when it quickly refreezes, the dust particles are fused to the larger body. So accretion occurs a little below the melting temperature, and the probability of sticking falls off as the distance from that appropriate zone increases, but there is no sharp boundary. The biggest body will be in the appropriate zone because most collisions will lead to sticking, and once the body gets to be of an appropriate size, maybe as little as a meter sized, it goes into a Keplerian orbit. The gas and dust is going slower, due to gas drag (which is why the star is accreting) so the body in the optimal zone accretes all the dust and larger objects it collides with. Until the body gets sufficiently large gravitationally, collisions have low relative velocity, so the impact energy is modest.

Once it gets gravitationally bigger, it will accrete the other bodies that are at similar radial distance. The reason is that if everything is in circular orbits, orbits slightly further from the star have longer periodic times, in part because they move slightly slower, and in part because they have slightly further to go, so the larger body catches up with them and its gravity pulls the smaller body in. Unless it has exactly the same radial distance from the star, they will pass very closely and if one has enough gravity to attract the other, they will collide. Suppose there are two bodies at the same radial distance. That too is gravitationally unstable once they get sufficiently large. All interactions do not lead to collisions, and it is possible that one can be thrown inwards while the other goes outwards, and the one going in may circularise somewhere else closer to the star. In this instance, Ceres has a density very similar to the moons of Jupiter, and it is possible that it started life in the Jovian region, came inwards, and then finished accreting material from its new zone.

The net result of this is that a major body grows, while smaller bodies form further away, trailing off with distance, then there is a zone where nothing accretes, until further out there is the next accretion zone. Such zones get further away as you get further from the star because the temperature gradient decreases. That is partly why Neptune has a Kuiper Belt outside it. The inner planets do not because with a giant on each side, the gravity causes them to be cleaned out. This means that after the system becomes settled, a lot of residues start bombing the planet. This requires what could be called a “Great Bombardment”, but it means each system gets a bombardment mainly of its own composition, and there could be no significant bombardment with bodies from another system. This means the bombardment would have the same chemical composition as the planet itself.

Accordingly, we have a prediction. Is it right? It is hard to tell on Earth because while Earth almost certainly had such a bombardment, plate tectonics has altered the surface so much. Nevertheless, the fact the Moon has the same isotopes as Earth, and Earth has been churned but the Moon has not, is at least minor support. There is, of course, a second prediction. There seem to be many who assume the interior of the Jovian satellites will have much nitrogen. I predict very little. There will be some through adsorption of ammonia onto dust, and since ammonia binds more strongly than neon, then perhaps there will be very modest levels, but the absence of such material in the atmosphere convinces me it will be very modest.

The Formation of the Giant Planets

Before I can discuss how we got the elements required for life delivered to Earth, it is necessary to work out how the planets formed, and why we have what we have. While the giant planets are almost certainly not going to have life, at least not as we would recognise it, they are important because what we have actually gives some important clues as to how planets form, and hence how common life will be, and why so many exoplanetary systems are so different from ours. The standard theory says a core accreted, then when it got sufficiently big, which calculations have at about 10 to 12 times the Earth mass it starts accreting gas in substantial amounts and it grows very slowly, the problem restricting growth being how it can compress its volume and get rid of the heat so generated. After a number of million years, its mass gets big enough, and it accretes everything that comes into range. Apart from the rather slow time the calculations give, that general description is almost certainly essentially correct. The reason we believe the core has to get to about 10 – 12 Earth masses before disk gases get accreted in serious amounts is because the evidence is the Neptune and Uranus have about 2 Earth masses of hydrogen and helium. So far, reasonably good. The fact that there is evidence the calculations are wrong is not damning; the fact that if the mechanism is not properly understood in close detail then the calculations will inevitably be wrong. The original calculations had these stages taking about 10 My to get to a planet the size of Jupiter. The very first calculations had it taking about a billion years to get to Neptune, but that obviously cannot be right because the disk gases had long gone before that. The real problem is how to get to the cores.

The standard theory says they started by the accretion of a distribution of planetesimals that were formed by the accretion of dust, and therefore were distributed according to the dust concentrations through the disk. There are two problems with this for me. First, we see these disks, and we see them because their dust scatters light. Some such disks are 30 My old and still dusty, so the dust itself is not rapidly accreting, altough often there are bands where there seems to be little dust. The second problem is that there is no recognized mechanism by which the dust can accrete and stick together strongly enough not to be disrupted by any other dustball that collides with it. Mathematics indicate that such dustballs, if they reach about 2 cm size, erode from gas motion relative to them.

So, how did the cores form? I think we have evidence from the fact their systems all have different compositions. The theory I outlined in my ebook Planetary Formation and Biogenesis goes like this. The dust that comes from deep space has a lot of very fluffy ice around it, and this has many pores. Within those pores, and around the ice, are the ices of other volatiles. (Such compound ices have been made in the lab, and their behaviour verified.) As the ices come in, the more volatile ones start subliming away at temperatures a little above their melting point, and hydrogen has even been maintained as an ice enclosed in water ice pores up to a little under 15 degrees K, which is well above its boiling point. So, as the ices come in and the disk gets gradually hotter, the ices selectively boil away. The relevant temperatures are: neon (~25 K); nitrogen and carbon monoxide (~65 K); argon and methane (~ 85); ammonia and methanol (~170 K); water (273 K).

What I suggest happened is the same mechanism that forms snowballs started planetary accretion. When snow is squeezed at a temperature a little below its triple point, the pressure causes localised melt fusion, and the particles stick together. In this case we have several ices entrained in the ice/dust, and I suggest the same happens for each ice. This has consequences. The temperature profile in these disks is observed to be where the temperature T is proportional to r^-0.75, r the distance from the star, with a significant variation, which is expected because the faster the gas comes in, or the warmer it was to start with, the further out a specific temperature will be found, while the denser the gas flow, the greater the temperature gradient. Now, because Jupiter is the biggest planet, and water ice is the most common single material, assume (like everyone else) that Jupiter is more or less where the water ice so fuses. If we assume the average disk temperature profile (actually r^-0.82 is better for what follows for our solar system) then the remaining giants are quite close to where they are supposed to be. So the mechanism is that ices come together, they hit, the collisional energy melts an ice in the impact zone such that they rapidly refreeze, and the particles stick together. To predict where the planets should be I put Jupiter at 5.2 A.U. as a water-ice core sets the constant of proportionality. The next ice is ammonia/methanol/water, which could melt between 164 – 195 oK, which suggests that Saturn should be between 7.8 – 9.6 A.U. Saturn has a semimajor axis of 9.5 A.U. The next ice out is methane/argon, with melting between 84 – 90 oK. The calculated position of Uranus is between 20-21.7 A.U., while the observed position is 19.2 A.U. The next ice, carbon monoxide/nitrogen melts between 63 – 68 oK, which predicts Neptune to be between 28.1 – 30.7 A.U., and Neptune has a semimajor axis of 30 A.U. Note that as they form, we excpect some movement through gravitational interactions and the effects of the gas.

This means the Jovian system is both nitrogen and carbon deficient, apart from Jupiter itself which accreted gas from the disk, and the very tenuous atmosphere of Europa is reported to actually have more sodium in it than nitrogen. Sorry, but no life under the ice at Europa because there is nothing much with which to have organic chemistry. The reason for the lack of atmosphere is the satellites have nothing in them that could form a gas at those temperatures. The major component is hydroxyl, from the photochemiclo deomposition of water, but this is extremely reactive and does not build up.

The Saturnian system has water, plus methanol and ammonia. The ammonia has been seen at Enceladus, and its decay product during UV radiation, nitrogen, is the main gas of Titan. The methane there will come from reactions of methanol and rocks. The Uranian system has methane and argon. Unfortunately the satellites are too small to have atmospheres, and Neptune’s satellites are similar, as while Triton has nitrogen volcanoes, it is probably a captured Kuiper Belt object, as it orbits Neptune the wrong way. However the atmosphere of Neptune has more nitrogen than expected from the accretion disk, whereas Uranus does not. More specific details are in the ebook, but in my opinion, the above describes reasonably well how these systems formed, and why they have the chemical composition we see. The Kuiper belt objects are the same as the core of Neptune, and are essentially a “tail” of the accretion process.

Finally, the perceptive will notice the possibility of two further zones of accretion. Further out, there will be a zone where neon trapped in ice might accrete, and even further out, because hydrogen can be trapped in ice even up to about 15 K, a hydrogen accretion zone where the liquid hydrogen dissolves neon, which then refreezes. The latter is not impossible. There are exoplanets a few hundred A.U. from the star, or, say, over ten times further than Neptune. On the other hand, there is a further mechanism that could form them, namely collapse of the disk, which presumably starts the star. So I should be able to predict where this planet 9 is? That is not so easy because the temperature of the disk follows the above relationship only approximately, and when we get down to these low temperatures, any deviation, including the initial temperature of the gas (which in the above relation is taken as zero, but it isn’t) suddenly becomes important. My published estimate for a neon-based planet is at a hundred A.U., with a possible minus 30 and a plus fifty A.U. Not exactly helpful. If I knew thie initial temperature, and the rate of heat loss from the disk by radiation at those distances I could be far more precise.

Was there an Initial Atmosphere from Accretion?

One of the problems with modern science is that once a paradigm has been selected, a layer of “authorities” is set up, and unless the scientist adopts the paradigm, little notice is taken of him or her. This is where conferences become important, because there is an audience that is more or less required to listen. The problem then for the person who has a different view is to show why that view is important enough to be considered. The barrier is rightly high. A new theory MUST do something the old one did not do, and it must not be contradicted by known facts. As I said, a high barrier.

In the previous post, I argued that the chemicals required for life did not come from carbonaceous chondrites or comets, and that is against standard thought. Part of the reason this view is held is that the gases had to come from somewhere, so from where? There are two obvious possible answers. The first is the gases were accreted with the planet as an atmosphere. In this hypothesis, the Earth formed while the disk gases were still there and simple gravity held them. Once the accretion disk was removed by the star, the hydrogen and helium were lost to space because Earth’s gravity was not strong enough, but other gases were retained. This possibility is usually rejected, and in this case the rejection is sound.

The first part of the proposition was almost certainly correct. Gases would have been accreted from the stellar disk, even on rocky planets, and these gases were largely hydrogen and helium. The next part is also correct. Once the disk gases were removed, that hydrogen and helium would be lost to space because Earth’s gravity was not strong enough to hold it. However, the question then is, how was it lost? As it happens, insufficient gravity was not the primary cause, and the loss was much faster than simply seeping off into space. Early in the life of a new star there are vicious solar winds and extreme UV radiation. It is generally accepted that such radiation would boil off the hydrogen and helium, and these would be lost so quickly that the other gases would be removed by hydrodynamic drag, and only some of the very heavier gases, such as krypton and xenon could remain. There is evidence to support this proposal, in that for krypton and xenon higher levels of heavier isotopes are observed. This would happen if most of these gases were removed from the top of the atmosphere, and since the lighter isotopes would preferentially find their way there, they would be removed preferentially. Since this is not observed for neon or argon isotopes, the argument is that all neon and argon in the atmosphere was lost this way, and if so, all nitrogen and carbon oxides, together with all water in the atmosphere would be lost. Basically, apart from the amount of krypton and xenon currently in the atmosphere, there would be no other gases. The standard theory of planetary formation has it that the Earth was a ball of magma, and if so, all water on the surface would be in the gas phase, so for quite some time Earth would be a dry lump of rock with an atmosphere that had a pressure that would be so low only the best vacuum pumps today could match it.

There could be the objection that maybe the star was not that active and we did retain some gases. After all, we weren’t around to check. Can you see why not? I’ll give the reason shortly. However, if we accept that the gases could not have come from the accretion disk, the other alternative is they came from below the ground, i.e. they were emitted by volacanic activity. How does that stand up?

One possibility might be that gases, including water, were adsorbed on the dust, then subsequently emitted by volcanoes. You might protest that if the Earth was a magma ocean, all that water would be immediately ejected from the silicates as a gas, but it turns out that while water is insoluble in silica at surface pressures, at pressures of 5000 atmospheres, granitic magma can dissolve up to 10% water at 1100 degrees C, at least according to Wikipedia. Irrespective of the accuracy of the figures, high temperature silicates under pressure most certainly dissolve water, and it probably hydrolyses the silicate structure and makes it far less viscous. It has been estimated that the water remaining in the mantle is 100 times greater than the current oceans so there is no problem in expecting that the oceans were initially emitted by volcanic activity. As an aside, deep in the mantle the pressures are far greater than 5000 atmospheres. This water is also likely to be very important for another reason, namely reducing the viscosity and lowering the magma density. This assists pull subduction, where the dry, or drier, basalt from the surface is denser than the other material around it and hence descends into the mantle. If the water were not there, we would not have plate tectonics, and if there were no plate tectonics, there would be no recycling of carbon dioxide, so eventually all the carbon dioxide on the surface would be converted to lime and there would be nothing for plants to use. End of life!

However, we know that our atmospheric gases were not primarily adsorbed as dust. How do we know that? In the accretion disk the number of nitrogen atoms is roughly the same as the number of neon atoms, and their heats of adsorption on dust are roughly the same. The only plausible physical means of separating them in the accretion disk is selective sublimation from ice, but ice simply could not survive where Earth formed. So, if our nitrogen came from the disk by simple physical means, then we would have roughly the same amount of neon in our atmosphere as nitrogen. We don’t, and the amount of neon we have is a measure of the amount of gas we have from such adsorption. Neon is present at 0.0018%, which is not very much.

So, in answer to the initial question, for a period there was effectively no atmosphere. To go any further we have to consider how the planets formed, and as some may suspect, I do not accept the standard theory for reasons that will become apparent in the next post.

Meanwhile, may I remind readers that my ebooks on Smashwords are on discount through July. Links to novels:

Puppeteer: http://www.smashwords.com/books/view/69696

‘Bot War: https://www.smashwords.com/books/view/677836

Troubles: https://www.smashwords.com/books/view/174203

Meanwhile, if you want to know scientifically about biofuels:

Biofuels: https://www.smashwords.com/books/view/454344

A Response to Climate Change, But Will it Work?

By now, if you have not heard that climate change is regarded as a problem, you must have been living under a flat rock. At least some of the politicians have recognized that this is a serious problem and they do what politicians do best: ban something. The current craze is to ban the manufacture of vehicles powered by liquid fuels in favour of electric vehicles, the electricity to be made from renewable resources. That sounds virtuous, but have they thought out the consequences?

The world consumption of petroleum for motor vehicles is in the order of 23,000 bbl/day. By my calculation, given some various conversion factors from the web, that requires approximately 1.6 GW of continuous extra electric consumption. In fact much more would be needed because the assumptions include 100% efficiency throughout. Note if you are relying on solar power, as many environmentalists want, you would need more than three times that amount because the sun does not shine at night, and worse, since this is to charge electric vehicles, which tend to be running in daytime, such electric energy would have to be stored for use at night. How do you store it?

The next problem is whether the grid could take that additional power. This is hardly an insurmountable problem, but I most definitely needs serious attention, and it would be more comforting if we thought the politicians had thought of this and were going to do something about it. Another argument is, since most cars would be charged at night, the normal grid could be used because there is significantly less consumption then. I think the peaks would still be a problem, and then we are back to where the power is coming from. Of course nuclear power, or even better, fusion power, would make production targets easily. But suppose, like New Zealand, you use hydro power? That is great for generating on demand, but each kWhr still requires the same amount of water availability. If the water is fully used now, and if you use this to charge at night, then you need some other source during the day.

The next problem for the politicians are the batteries, and this problem doubles if you use batteries to store electricity from solar to use at night. Currently, electric vehicles have ranges that are ideal for going to and from work each day, but not so ideal for long distance travel. The answer here is said to be “fast-charging” stops. The problem here is how do you get fast charging? The batteries have a fixed internal resistance, and you cannot do much about that. From Ohm’s law, given the resistance, the current flow, which is effectively the charge, can only be increased by increasing the voltage. At first sight you may think that is hardly a problem, but in fact there are two problems, both of which affect battery life. The first is, in general an overvoltage permits fresh electrochemistry to happen. Thus for the lithium ion battery you run the risk of what is called lithium plating. The lithium ions are supposed to go between what are called intercalation layers on the carbon anode, but if the current is too high, the ions cannot get in there quickly enough and they deposit outside, and cause irreversible damage. The second problem is too fast of charging causes heat to be generated, and that partially destroys the structural integrity of the electrodes.

The next problem is that batteries can be up to half the cost of the purely electric vehicle. Everybody claims battery prices are coming down, and they are. The lithium ion battery is about seven times cheaper than it was, but it will not necessarily get much cheaper because at present ingredients make up 70% of the cost. Ingredient prices are more likely to increase. Lithium is not particularly common, and a massive increase in production may be difficult. There are large deposits in Bolivia but as might be expected, there are other salts present in addition to the lithium salts. There is probably enough lithium but it has to be concentrated from brines and there are the salts you do not want that have to be disposed of, which reduces the “green-ness” of the exercise. Lithium prices can be assumed to go up significantly.

But the real elephant in the room is cobalt. Cobalt is not part of the chemistry of the battery, but it is necessary for the cathode. The battery works by shuttling lithium ions backwards and forwards between the cathode and anode. The cathode material needs to have the right structure to accommodate the ions, be stable so the ions can move in and out, have valence orbitals to accommodate the electron transfer, and the capacity to store as many lithium ions as possible. There are other materials that could replace cobalt, but cobalt is the only one where, when the lithium moves out, something does not move in to fill the spaces. Cobalt is essential for top performance. There are alternatives to use in current technology, but the cost is in poorer lifetimes, and there are alternative technologies, but nobody is sure they work. At present, a car needs somewhere between 7 – 20 kg of cobalt in its batteries, and as you reduce the cobalt content, you appear to reduce the life of the battery.

Cobalt is a problem because the current usage of cobalt in batteries is 48,000 t/a, while world production is about 100,000 t/a. The price is increasing rapidly as electric vehicles become more popular. At the beginning of 2017, a tonne of cobalt would cost $US 32,500; now it is at least $US 80,000. Over half the world’s production comes from the Democratic Republic of Congo, which may not be the most stable country, and worse, most of that 100,000 t/a comes as a byproduct from copper or nickel production. If there were to be a recession and the demand for stainless steel fell, then the production of cobalt would drop. The lithium ion batteries that would not be affected are the laptops and phones; they only need about 10 – 20 g of cobalt. Even worse, there are a lot of these batteries that currently are not being recycled.

In a previous post I noted there was not a single magic bullet to solve this problem. I stick to that opinion. We need a much broader approach than most of the politicians are considering. By broader, I do not mean the approach of denying we even have a problem.

This post is later than my usual, thanks to time demands approaching Easter, and I hope all my readers have a relaxing and pleasant Easter.

Neanderthal Culture

We like to think that culture separates humans from animals, but what is the sign of culture? The reason this is of interest is that recently cave art has been discovered in some Spanish caves that is at least 60,000 years old, which means that it was drawn by Neanderthals as Homo sapiens did not arrive in Europe for another 20,000 years. It is not as distinctive as some of the cave art found in French caves, but that may not be surprising, since it has had to last an additional 30,000 years or so, and some has been dated to over 100,000 years.

Neanderthals are often considered as unsophisticated brutes, incapable of art, and far less technically capable than us. That has often been argued because Homo sapiens made quite sharp arrowheads and Neanderthals did not. It is true that Homo sapiens also made sharper spear tips, but this may be because the two races/species hunted differently. The Neanderthals were ambush hunters in the ice age forests whereas Homo sapiens arrived as grass-lands were appearing, and had to hunt in the open. This may be why the Neanderthals gave way: they simply could not get enough food. That we shall never know. There is also an argument that we have a few per cent of Neanderthal genes, which means the two interbred, which to me suggests they were simply different races and not different species.

As for being clumsy brutes, I saw in a museum near the palace at Versailles some artifacts, and yes, by and large the weapons used by the Neanderthals for hunting were far more clumsy looking, and would need a lot more power to use. But they were far more powerful. They had strength, but not stamina. They had not mastered flint knapping, and I am not sure whether they even knew about flint. We have to be careful in making such statements because although we have a number of artefacts, they tend to have been collected from a few very selected places, and during an ice age, the supply or resources may have been considerably less. However, at this museum there was also a bone flute that was attributed to them. If so, that means they made music. The caves also contained shells with holes pierced in them, strongly suggestive that the shells were made into necklaces.

Now the paintings. The way we know how old they are is interesting. The cave artists used inorganic pigments, by and large, although the black may have been carbon. However, the dating was done by a particularly crafty means. The paintings have a thin layer of calcite over them, deposited by groundwater seeping down over them. The water contains tiny levels of uranium, and when lodged in the calcite, it decays to thorium. (Thorium oxide is effectively insoluble in water, so it would not have been in the original water.) The uranium/thorium ratio allows us to date the calcite, and interestingly, although this layer is relatively thin, they have been able to shave it and find that the deeper calcite is indeed older.

So they drew, they made music, they adorned themselves. Not that much different from us.

A Ball on Mars

In New Zealand we are approaching what the journalists say is “The Silly Season”, the reason being that what with Christmas and New Year, and with it being in the middle of summer, a lot of journalists take holidays, and the media, with a skeleton staff, have to find almost anything to fill in the spaces that the media makes available. So, in the spirit of getting off to an early start, I noticed an image from Mars that looks as if someone left a cannon ball lying around. (The image is easily found on the web, but details are not, so I am not sure where it was found.) So what is it?

Mars_Ball

Needless to say there were some loopy suggestions from “the fringe”, but while it is easy to scoff, it is not so easy to try to guess what it is. The idea of a cannon ball and nothing else borders on the totally bizarre. So what can we see from the image? The remarkable point about this object is it seems to be lying on the surface, which suggest it did not strike it, as otherwise there would be indentations, or, if it were a meteorite, there would be a crater. There clearly isn’t. Equally, however, it looks smooth, which suggests it has been fused, which means it did not arise there. Some have suggested it is a haematite spherule, but that, to me is not that likely, in part because it is so large (the so-called “blueberries” were quite small) and also because there seems to be only one of it, while what created the “blueberries” created a lot of them. In my opinion, it is probably an iron meteorite, and the reason there is no impact crater is that it landed somewhere else, and rolled to this spot.

So maybe time to get a little more serious, and think about iron meteorites. What can we say about them? The Curiosity rover has also found “Egg rock”, which is an iron meteorite about the size of a golf ball. The Rover found iron, nickel and phosphorus as significant constituents, and the phosphorus is present as iron phosphide. There are two important issues here: how did the iron/nickel ball form separately from everything else, and equally important, how did iron phosphide form? That last question may need explanation, because phosphorus does not normally occur as a phosphide, and phosphides only form under highly reducing conditions. (Reducing conditions are usually in the presence of hydrogen and or an active metal at higher temperatures. The opposite, oxidising conditions, occurs when there is oxygen or water present, but not enough hydrogen or metal to scavenge the oxygen.)

Iron phosphide is known to occur in certain iron meteorites, but such meteorites can always be attributed to having formed at a little more than 1 A.U. from, or closer to the star. Chondrites that formed further out, such as in the asteroid belt, always have their phosphorus in the form of phosphate, which is a very stable, oxidised, phosphorus compound. The point about 1 A.U. (the distance of Earth from the sun) is that was where the temperatures were hot enough to melt iron, and the phosphide would form by the molten iron reacting with phosphate to form the phosphide and iron oxide.

Now for the reason for going on about this. One of the JPL team explained that iron meteorites originated from the cores of asteroids. The premise here is that during initial accretion, the dust assembled into an asteroid-sized object, the object got sufficiently hot and the iron and nickel melted and sunk to the core. Later, there was a massive collision and the asteroid’s core shattered, and the meteorites we see are the fragments from the shattering. (Note, the same people argue planets formed by asteroid sized bodies, and bigger, colliding and everything stick together. Here is having your cake and eating it in action.) The first question is, why did the rock melt? One possibility is radioactive isotopes, so it is possible, nevertheless for the explanation to work the asteroid had to melt hot enough to melt iron, and to hold those temperatures for long enough for the iron to work its way to the centre through the very viscous silicates in a very weak gravitational field. A further problem is that the phosphate would dissolve in the silicates, in which case it would not form iron phosphide because the iron would not get there. Calcium phosphate has a density of about 3, very similar to many of the silicates, so it might be difficult for iron phosphide to form in such an asteroid. Only a very few asteroids, and Vesta is one, have iron cores, and there are some reasons to believe Vesta formed somewhere else and moved.

The reason for my interest is that in my ebook, “Planetary Formation and Biogenesis” I argue that the first way accretion started was for the dust in the accretion disk to get hot enough to get sticky, or to form something that could later act like a cement. When the temperatures got up to about 1550 degrees Centigrade, iron melts and in the disk would form globules that would grow to a certain degree. Many of these would also find molten silicates to coat them, so the separation occurred through the temperature generated by the accreting star. Provided these could separate themselves from the gas flow (and there is at least a plausible mechanism) then these would become the raw materials for rocky planets to form. That is why (at least in my opinion) Earth, Venus and Mercury have large iron cores, but Mars does not.

That, of course, has got a little away from the “Martian cannonball” but part of forming a scientific theory is to let the mind wander, to check that a number of other aspects of the problem are consistent with the propositions. In my view, the presence of iron phosphide in an iron meteorite is most unlikely to have come from the core of an asteroid that got smashed up. I still like my theory, but then again, I suppose I am biased.