Where now, Britain?

I suppose many will be sick of Brexit now, nevertheless I feel like adding my tuppence worth. My futuristic novels generally have some aspect of alternative governments in the background, or as settings for the stories, and in some ways the Federal form in one of the trilogies, and in one other story, has similarities with the EU. The reason I raise this is because I do not feel that Brexit was just a wildly irrational thing to do (and that does not mean I think it was a good thing to do) but rather I think it was a failure of governance on the part of the EU, and a failure of leadership by Cameron.

Take as an example, one Brit I saw interviewed stated his wages were reduced by three quid an hour recently, and his employer did that simply because said employer could get cheaper labour from Eastern Europe. With free movement of labour, wages fall to the lowest available, but the cost of living does not fall correspondingly. The benefits of said lower wages fall into the laps of the employing class. Accordingly, we might suspect the EU bureaucrats are more interested in assisting the welfare of the rich than considering that of the masses. Now, if that happened to you, would you vote to retain such competition for your job? More than one who voted to leave, when interviewed, said something like, “I’m broke, so I vote to break the system that broke me.”

There were two interesting concentrations of votes to remain. The first was in London, where many are professionals, and many are cheap labour from the East, both of whom benefited greatly from remaining. The second was from Scotland, and my guess is some of that was insurance: if exit won, the Scots would wish to exit from the UK and hope their voting for the EU would let them remain in the EU. In short, it was partly a vote to exit from the UK.

The votes to leave apparently mainly came from the unemployed or the wages class, and those with lower levels of education. They also came from the places that used to be part of the UK industrial zones (except for Glasgow, and it was interesting that although Glasgow voted to remain, the turnout was seriously down there, in accord with the theory that they wanted Scotland out of the UK).

There have been threats of dire economic consequences. I do not believe that trade will suffer significantly. Germany sells a lot of manufactured things to the UK, and it is hardly likely to want to lose those sales, and if it wants to keep its sales, it has to permit the UK to sell into the EU. An important point is that neither the manufacturing base nor the demand from people will change dramatically. The main danger is spiteful “punishment”. Undoubtedly there will be adverse economic consequences, and probably the one the EU fears the most is further exits. Greece must be seriously considering it.

The fact that the stock markets went crazy intially is irrelevant. As one of our Prime Ministers once noted, stock traders tend to behave like reef fish: as soon as one heads off in a new direction, all the rest follow. There was another interesting aspect of these markets, and that is a lot of smart traders took short positions. This tends to stop total collapse because the shorts have to be covered, and a sensible trader takes a good profit when on offer. Further, it did not last. At the time of writing this, the FTSE 100 was up on pre-referendum prices.

Another major concern with the EU is the influence of the bureaucrats and technocrats, and it is designed to protect entrenched interests. Thus given the bad choices by BOTH participants, it is the Greeks that must suffer rather than the owners of the German banks. The British, at least, see the EU run to maintain the traditional class system, and if you happen to be nearer the bottom, why maintain it? Over the last decade, the system has run in a way in which the establishment has caused considerable financial chaos through a mix of greed and ineptitude. So who pays? Not those who caused it. Sure, they will have taken hits, but the wealth continues to trickle up in their direction. A week later and some reality is setting in. Some of the countries like Poland and the Czech Republic have expressed concern that Germany, Italy and France are starting to take too much control; they saw the UK as an important counterbalance.

Meanwhile, the overall level of common sense seems to be diving. I have seen some commentators claim the exit is not necessarily going to happen. One way out is for the government to call an election, and if Labour won, they could take that as an endorsement not to leave. The problem with that reasoning is that it is the people who would normally vote Labour who voted to leave. Meanwhile, there was a massive vote of no-confidence in Corbyn, the Labour leader, by his party politicians because he did not campaign strongly to remain. Corbyn refuses to step down, showing a strong commitment to democracy and convention, but perhaps he is right because it is the people who he represents that voted to leave. Meanwhile Cameron has lashed out, saying he should do the decent thing and go for his failure. Failure for what? Rescuing Cameron from his ineptitude?

So, what now? I recently saw a speech from a “leaver” to the EU parliament (at least I think it was) and it was a dreadful example of diplomacy. If ever someone tried to maximise the irritation of his audience, this would have been an example, and the sad thing is, I don’t think it was intended that way. Instead it was simple uncaring stupidity. This makes no sense at all. As to what will happen next, I don’t think anyone knows, which shows the ineptness of Prime Minister Cameron. You should never call a binding referendum unless you have a reasonably clear idea of what you will do if either side wins. Cameron seems to have decided he knew what he would do if remain won: nothing. Unfortunately, that seems to have been his option if exit won, and it is simply not adequate.

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Where did Earth’s water and air come from?

If you accept my picture of how rocky planets form, we are now able to look at the volatiles. As before, this is my interpretation of what happened, and is not standard. Water is obvious, and was discussed in the previous post: water was what cemented the rocky fragments together, and the amount of water present in the rocks was proportional to the amount of cement present, and dependent on which type. Earth has the most water because it was in the optimal distance from the star; Venus had less because it was hotter, and because more of it came from basaltic rocks; Mars had less because it did not have many free aluminosilicates. The current geologies are consistent with this interpretation, although of course the evidence from Venus is a little on the thin side.

The accretion of carbon is more difficult to describe. At Earth’s distance from the star, essentially all carbon was in the form of carbon monoxide. However, there is another possible source, through what the chemist calls the reactive intermediate. The concept is that on dust there would be very low levels of methanol formed by reacting carbon monoxide and hydrogen, and that would immediately decay to form what is called “coke” when this process is carried out in a methanol-making plant. Such coke is a solid, and solids on the dust can be accreted. There should also be more chemistry, to make carbides, which are important for the origin of life, but not for the present discussion.

Similarly, at temperatures over 1000 degrees centigrade, nitrogen can react with a number of materials to form nitrides, which in turn are solids. Such solids will be accreted into the planet with the dust.

As the planet accretes, the interior heats up, simply through gravitational energy. I do not believe the standard theory is correct as far as major collisions are concerned, but irrespective the centre will heat, and together with radioactive decay, the centre and some way out becomes molten. At this point three things happen. Molten iron sinks to the core (thus generating more gravitational energy, and at the same time, the separated aluminosilicates can rise, forming the continents. The water becomes vapour, some of which dissolves in the hot silicate, and the rest either rises to form the oceans, or reacts chemically with something.

There are two important options regarding reaction, and it is important to note that these consume the number of moles of water that are reacted. The first is to oxidise something, like iron. That makes iron oxide, such as magnetite, which may also react with silica to make olivines and pyroxenes, together with some additional special minerals. Reaction of water with hot carbon makes carbon monoxide and hydrogen, the so-called synthesis gas. The second is to react with carbides and nitrides to make materials like methane, acetylene, hydrogen cyanide and ammonia, and at the same time, make oxides. Synthesis gas is in an equilibrium, and under pressure tends to end up as methane. Ammonia is in equilibrium with hydrogen, with pressure favouring ammonia. Geological pressures are far higher than anything we can achieve in a laboratory. So this theory predicts that the initial atmosphere will contain significant amounts of methane and ammonia, which will be degraded by UV radiation from the star to form, with water, carbon dioxide, nitrogen, and hydrogen, the latter being lost to space. So, is there any evidence for this, besides the prevalence of continents?

The first example comes from some rocks from Isua, Greenland, that are 3.8 billion years old. They contain primitive atmosphere in inclusions, as foamy magma congealed. The major gas inside is methane. The second comes from similar rock inclusions from 3.2 billion years ago from Barberton, in South Africa. This too involves magma that appears to have trapped seawater in pores. The salt levels are somewhat higher than modern seawater, presumably because the magma tended to boil off some of the water before it was trapped. What remains are ammonia levels approximately the same level as potassium ions. To me, that means the sea must have had high levels of ammonia in it, and assuming the ratio of nitrogen atoms to water was roughly the same as now, this would indicate that about ten per cent of the planet’s nitrogen was still in the form of ammonia then.

I also believe this mechanism better accounts for planetary deuterium/hydrogen ratios, which are always higher than the star’s. The standard explanation for that is that UV radiation from the star breaks down water, but water with deuterium in it is slightly heavier than ordinary water, so on density grounds it tends to rise less and a little hydrogen is preferentially lost to space. This enhancement is somewhat slight, but if it goes on for long enough, it will increase deuterium levels. From memory, the D/H ratio on Mars is about five times that of Earth, and we know that there are other isotope enhancements, due to the weaker Martian gravity, hence lighter molecules can be physically swept off to space. However, we now come to a problem with Venus, that has at least 100 times the enhancement. If this arose from such photolysis, what happened to the oxygen? This issue is serious because we then have to ask why does Earth not lose water the same way? The answer is that photolysis of water that would enhance deuterium also makes oxygen, and the oxygen makes ozone, and he ozone protects the water. It is also not a very rapid process, and if there was sufficient water on Venus, why did it not fix the carbon dioxide and make lime, like on Earth? The argument that it was hotter, and under pressure, is irrelevant: the hotter the water, the faster it reacts with rock.

My answer is simple. When the water reacts with solids as described above, there is something called the chemical isotope effect that is relevant. That means an O – H bond in water will react somewhere between 4 – 20 times preferentially than an O – D bond. Further, the water will not contain D2O, but rather H – O –D, which in turn will preferentially react the hydrogen atom. Unlike density differences, which is the cause of the vaporization and reaction in the upper atmosphere, this preference depends on the zero point vibrational energy of the bonds, and that makes very significant differences to the activation energy for the reactions. Thus for me, Venus never had significant water on its surface; the lesser amount of water it accreted was largely used up making the huge atmosphere, and whatever remains dissolved in the silicates of the lower mantle.

Next Monday post I should be able to explain the Martian fluvial systems.

Justice, or Authorities being Self-important

This week, there were two news items that I found to be somewhat disquieting for the reason that they do not reflect justice. The first was the banning of Russian athletes from the Olympics, and as far as I can make out, from other sporting events. The reason was that there was a lot of doping amongst Russian athletes. Now, to ban those who were found to have taken drugs is fine by me. They were guilty of breaking the rules so they should pay. However, a blanket ban seems to go against natural justice: guilt by association. Notice that during the time of Lance Armstrong, it turned out all his cycling associates were also doing that, but did anyone suggest banning all American cyclists? Of course not. Banning the guilty is fine, but blanket banning as a punishment for the nation was never considered. So why the Russians? Has it got anything to do with a general anti-Russian sentiment? We shall never know, but punishment by association is, in my view, wrong. More to the point, if it were that prevalent, why weren’t the authorities doing something about it when it was more important to do it, even though the publicity value would be much less? Why don’t they simply test all athletes at the Olympics?

Seemingly, the powers that be decided that, yes, this procedure was either bad, or, more importantly to them, it could be seen to be bad. So something had to be done to give the impression of fairness. So, what did they come up with? Why, each athlete would be given the opportunity to prove they had not doped. How? Hmmmm! That is yet to be decided, but the athletes should start proceedings. Yeah, right! With two months to go to the biggest sporting event, instead of training, they should engage in some undefined bureaucratic procedure. Sorry, but in my opinion, the role of these authorities is to be fair and enforce the rules. It is not to make themselves feel good, and thwart criticism by mounting publicity charades.

The next item involved the trial of the 94 year-old Reinhold Hanning. Again, Hanning was guilty by association, although in this case he was associated with mass genocide. Hanning joined the Hitler youth in 1935, and that was not considered a criminal organization at the time. In 1940 he joined the Waffen SS, and fought on the eastern Front until he was severely wounded by grenade splinters. He was deemed unfit for further combat duties, and ordered to go to Auschwitz, where he was first assigned to register work details, and later for duty in a guard tower. No evidence was provided that Hanning had any part personally in killing, or in selection for killing.

My first problem with this is, suppose you were in Hanning’s shoes, and ordered to Auschwitz, what would you do? Disobey any order, or start protesting, and you would be on the other side of the fence. How many of you would take that stance? Is it even a sensible stance? You get killed and you achieve nothing. Think about this, and if you are so confident you would throw away your life, please add a comment and explain why.

My next problem with this procedure is that following the war, it was estimated that about 10% of the German population had been members of the Nazi party. After all, that was the way to get ahead. In 1963 – 1965, trials of second and third tier personnel at Auschwitz led to convictions of only the worst sadists being convicted for murder, and defendants argued successfully that they had only been following orders. If the justice system could not be bothered prosecuting someone like Hanning then, then why now? Basically, about 50 people have been convicted of crimes at Auschwitz, and up to 7000 people worked there.

In 2011, there was an alleged “breakthrough”. Legally, they decided that if you worked at a factory of death, that made you an accessory to murder because without the likes of you, the place could not have run. That is true, but the question then is, were you a voluntary participant? I am not so sure that the desire to stay alive yourself makes you an accessory.

A related problem with the trial is the argument is made that seventy years ago the German courts “made a mistake” and now is the time to correct it. As one legal scholar put it, this trial is symbolically important for the German legal system, and it helps the survivors. I am afraid I do not agree, and the issue is the same as for the Russian athletes. Justice should reflect guilt. The desire by authorities to feel good, or to wipe out traces of their own useless performance, has no place.

And just to clarify my position, I have walked through Auschwitz before there were many tourists. It was an awful place. I remember the fertile mounds that were the remains of the crematoria. I also remember the chalk drawings where the victims tried to record the horrors in a way that the SS would not erase. I also had an uncle in Dachau so I have no sympathy at all for those guilty of creating those places. But I would never put a 94 year-old on trial for “guilt by association” merely to make myself look as if I were doing something.

How do Rocky Planets Form?

In my previous post, I argued that no simple physical process leads to the rocky planets having an atmosphere. Something was missing, and to explain what, I need to discuss how rocky planets formed in the first place. The standard theory starts with a distribution of planetesimals through space, and these gravitationally accrete. For me there are several things wrong with this theory. The first is there is no known mechanism to get the planetesimals, which can be considered as medium-sized asteroids, say something like 50 km radius, although they would not usually be round. Various theories as to how dust could form planetesimals invariably fail, the problem being if you can persuade dust to accumulate, abrasion turns it back to dust because it has no strength. If you can get to rocks, then these are argued to attract and form rubble piles, but if two such piles collide, what happens next will be like a snooker break. A pile of stones does not join together, let alone a mass of sand, without some other agent.

The next problem is the time taken to form the planets. Early computations on accretion, omitting any degradation, had this as about 100 million years (100 My). When it became obvious that this was wrong (e.g. the moon probably formed after 30 – 60 My) the time got reduced, although nobody said how. We are now reasonably confident that Mars formed within three million years, and no collisional theory as yet can get it formed that quickly. One problem is the small bodies that form initially are entrained in gas and hence in circular orbits, when they never meet. If we assume a physical process, all accretion is at the same rate, leaving aside concentration as a function of distance. As the bodies grow, to collide they need some degree of eccentricity, and the greater the eccentricity, the more violent the collisions. There are examples of such collisions that have occurred in the asteroid belt; almost inevitably the net result is fragmentation, not growth, and the so-called asteroid families remain.

There are also some questions to answer, such as why is Mars so small? Why is there so little between Mars and Jupiter? If you argue that Jupiter upset the mass in this zone, why are the asteroids in almost circular orbits, apart from the “families”?

So, if there is no obvious physical mechanism to start rocky planet accretion, as a chemist I had to think in terms of chemistry. To start, there are three relevant time periods. The first is during stellar accretion, when mass pours into the forming star. The disk temperature now falls off from the star according to about r^-0.75, with temperatures around Earth reaching about 1600 degrees C. Study of such disks elsewhere suggest this stage takes about 1 My. Then the rate of inflow from the disk more or less decreases by about three to seven orders of magnitude, and the disk cools to temperatures similar to those today, with the main source of energy being radiant heat from the star. This second stage can last somewhere between 1 – 30 My. Eventually the star ignites its fusion reactions and there is a significant outflowing of mass, which clears away the accretion disk and any small dust. At this time, there is also a radial distribution of certain isotopes, thus the amount of 17 and 18 oxygen will vary by a few ppm radially, which gives us clues as to where various rocks, etc came from.

The conclusion is, most of the material on any given body in the solar system accreted from material from its own zone, i.e. there was none of the mixing expected from standard collisional theory. The Moon accreted from material in Earth’s zone, or from Earth material. Of course there are problems with such a statement, as we only have samples from Earth, Moon, Mars and some asteroids. So, what are the options remaining for accretion?

The first is if a body can get big enough very quickly. The early solar system had a certain level of 26Al, an isotope that decays with a half-life of 75,000 years. If enough could be trapped inside a large enough body, the heat generated would be enough to melt silicates, and you would end up with a large rock. The problem is to get the body sufficiently big in the first place. However, if you have any mechanism to get a rocky body of sufficient size in the first quarter My or so, that heating could make the object stronger.

My concept is a little different. As the dust in the early accretion disk approaches the forming star it gets hotter. Silicates a little above bright red heat start to get sticky, so dust will agglomerate into small stones. Hotter still, and some liquids start to form, and an important point is that different types of liquids are often mutually immiscible, so you will get phase separation. There are some key temperatures. Specifically, about 1550, iron will liquefy, and globs of iron will merge with other such globs. Above this temperature, iron filled bodies will form, and these may get covered in silicates. About 1250 degrees C, calcium silicate starts to phase separate; about 1500 degrees a series of calcium aluminosilicates start to phase separate, while about 1800 degrees C silicates themselves start to dramatically lose viscosity. The closer to the star, the larger the boulders, and plausibly most of Mercury could have accreted by this mechanism.

The problem now is to accrete the stones into larger bodies in the second stage, i.e. with lower temperatures and some disk gas remaining. Significant collisions will lead to fragmentation and dust formation, and we observe such dust, even in old disks. A larger body orbits with Keplerian motion, but the smaller ones get entrained in the gas and gradually fall towards the star. Accordingly, larger bodies will get continually struck gently by smaller objects, and any such grouping will collect dust. Now, the important point is in certain zones that experienced appropriate temperatures there will be phases of certain materials such as calcium silicate and calcium aluminosilicates, and these are hydraulic cements. Accordingly, water vapour will set the cements. Mars would have to rely only on essentially the calcium silicate type cement, which sets with one mole equivalent of water. Earth would be in an optimal position. There would be iron containing boulders, and the cements would include the calcium aluminosilicates, which can set up to fifteen mole equivalents of water. Venus is in a less desirable zone from the point of view of cement, because the higher temperatures from the star would inhibit the setting, nevertheless, once underway, the concentration of boulders is higher than around Earth.

What evidence is there for this? Perhaps the most impressive is that Earth has continents. These are granitic/feldsic, and are based on aluminosilicates. The reason is that granite and feldspar have relative densities about 2.5 – 3, whereas the basalt that makes up the bulk of the planet has a density > 3. So the continents float on the mantle, like icebergs. Venus is hard to get evidence, however there are two modest continents that are likely to be granitic. Mars has generally much lower levels of aluminium, and has no granite as far as we can tell, although on Syrtis Major there are kilometer-thick sheets of plagioclase, which can be thought of a s a sort of mix of granite and basalt. This also accounts for the atmospheres, but that is for the next Monday post.

Is this mechanism realistic? The Japanese Space Agency sent a mission to the small asteroid Itokawa, and it turned out that it had seemingly formed and had never been struck by anything of significance since. I am attaching an image, which I interpret as two larger boulders having met and been joined together by a concrete in the middle, and the result also grew somewhat by small material landing on it and being cemented on. But then I am biased, having formed this theory. Your thoughts?

Itokawa2

Hawking’s Genius

How do people reach conclusions? How can these conclusions be swayed? How do you know you are correct, as opposed to being manipulated? How could a TV programme about physics and cosmology tell us something about our current way of life, including politics?

I have recently been watching a series of TV programmes entitled Genius, in which Stephen Hawking starts out by suggesting that anyone can answer the big questions of nature, given a little help. He gives them some equipment for them to do some experiments, and they are supposed to work out how to use it and reach the right conclusion. As an aside, this procedure greatly impressed me; Hawking would make a magnificent teacher because he has the ability to make his subjects really register the points he is trying to make. Notwithstanding that, it was quite a problem to get them to see what they did not expect. In the first episode there was a flat lake, or that was what they thought. With more modern measuring devices, including a laser, they showed the surface of the lake was actually significantly curved. Even then, it was only the incontrovertible evidence that persuaded them that the effect was real, despite the fact they also knew the earth is a sphere. In another program, he gets the subjects to recognise relative distances, thus he gets the distances between the earth and the moon by eclipses, then the distance to the sun. The problem here is the eclipses only really give you angles; somewhere along the line you need a distance, and Hawking cheats by giving the relative sizes of the moon and the sun. He makes the point about relative distances very well, but he overlooks how to find the real distances in the first place, although, to be fair, in a TV program for the masses, he probably felt that there was only a limited amount to be covered in one hour.

It is a completely different thing to discover something like that for the first time. Hawking mentions that Aristarchus was the first to do this properly, and his method of getting the earth-moon distance was to wait for an eclipse of the moon, and get two observers some distance apart (from memory, I believe it was 500 miles) to measure the angle from the horizontal when the umbra first made its appearance. Now he had two angles and a length. The method was valid, although there were errors in the measurements, with the result he was out by a factor of two. To get the earth-sun distance, he measured the moon-earth-sun angle when the moon was precisely half shaded. The second angle would be a right angle, he knew the distance to the moon, so with Pythagorus, or, if he were into trigonometry that was not available then, secants, he could get the distance. There was a minor problem; the angle was so close to a right angle and the sun is not exactly a point, and the half-shading of the moon is rather difficult to get right, and of course his actual earth-moon distance was wrong, so he had errors here, and had the sun too close by a factor approaching 5. Nevertheless, with such primitive instruments that he had, he was on the right track.

Notwithstanding the slight cheat, Hawking’s demonstration made one important point. By giving the relative sizes and putting the moon about 5 meters away from the earth (the observer) to get a precise eclipse of the given sun, he showed what the immense distance really looks like proportionately. I know as a scientist I am often using quite monstrous numbers, but what do they mean? What does 10 to the power of twenty look like compared with 10? Hawking stunned his subjects when comparing four hundred billion with one, using grains of sand. Quite impressive.

All of which raises the question, how do you make a discovery, or perhaps how do discoveries get made? One way, in my opinion, is to ask questions, then try to answer them. Not just once, but every answer you can think of. The concept I put in my ebook on this topic was that for any phenomenon, there is most likely to be more than one theoretical explanation, but as you increase the number of different observations, the false ones will start to drop out as they cannot answer some of the observations. Ultimately, you can prove a theory in the event you can say, if and only if this theory is correct, will I see the set of observations X. The problem is to justify the “only if” part. This, of course, goes to any question that can be answered logically.

However, Hawking’s subjects would not have been capable of that because the first step in forming the theory is to see that it is possible. Seeing something for the first time when you have not been told is not easy, whereas if you are told what should be there, but only faintly, most of the time you will see it, even if it isn’t really there. There are a number of psychological tests that show people tend to see what they expect to see. Perhaps the most spectacular example was the canals on Mars. After the mention of canali, astronomers, and Lovell in particular, drew lovely maps of Mars, with lines that are simply not there.

Unfortunately, I feel there was a little cheating in Hawking’s programs, which showed up in a program that looked at whether determinism ruled our lives, i.e. were we pre-programmed to carry out our lives, or do we have free will? To do this, he had a whole lot of people line up, and at given times, they could move one square left or right, at their pleasure. After a few rounds, there was the expected scattered distribution. So, what did our “ordinary people” conclude? I expected them to conclude that that sort of behaviour was statistical, and there was really choice in what people do. But no. These people conclude there is a multiverse, and all the choices are made somewhere. I don’t believe that for an instant, but I also don’t believe three people picked off the street would reach that conclusion, unless they had been primed to reach it.

And the current relevance? Herein lies what I think is the biggest problem of our political system: people can be made to believe what they have been primed to believe, even if they really don’t understand anything relating to the issue.

Where did our water and air come from, and what form was it in?

If we want to answer the question, how likely is there to be life on other planets, then these questions must be answered because life depends on these elements. Also, to answer questions such as how the catastrophic floods on Mars could have occurred also requires answers to where the materials for the floods came from. The questions are also of interest because they illustrate what I think is an ideal method for solving problems, and that is to ask questions and from the answers, eliminate what could not have happened. This gets to Conan Doyle’s mantra: if you have eliminated all but one, even if it seems unreasonable it must be what happened.

First, all material came from the accretion disk, and that got hotter and hotter as it fell into the sun. While the sun was accreting rapidly, temperatures a bit further away than where Earth is now reached about 1550 degrees Centigrade, and much of the material present at the end of rapid accretion made up the material from which the rocky planets formed. We know that because iron melted, we now have iron meteorites, and Earth has a large iron core, whereas Mars has much less iron in its core. (It would still accrete some iron, which would melt, but a lot would also oxidise and form rust if it were finely divided.) The gases in the disk at these temperatures and likely pressures would be mainly hydrogen, helium, water, carbon monoxide, nitrogen, neon, followed by a number of lesser gases. There came a point where the sun’s rate of accretion reduced by several orders of magnitude. The disk that remained now formed the rocky planets, and these planets formed rather quickly. Mars apparently formed within three million years, although of course bombardment led to some additional mass being added later.

So, where did the rocky planets’ atmospheres come from.

Option 1. The rocky planets formed and gravity started to hold atmosphere. We have the residue, after the hydrogen and helium was lost to space. This is obviously wrong. If our air arrived that way, then there should be roughly the same amount of neon in the air as nitrogen, but neon is extremely rare, although some of the krypton and xenon may have survived from this period. Accordingly, the early earth, and presumably the other rocky planets, were basically lumps of rock without atmosphere or oceans.

Option 2. The volatiles were delivered by comets. This was what was thought to be the case for some time, but while some comets probably have struck the earth, they are not considered to be a significant source of water or air. The reason is that the levels of deuterium in comets is about five times that of our seawater. You can concentrate the levels of deuterium by boiling off water, and you would have to lose the hydrogen to space, but you cannot concentrate the hydrogen. There have also been claims that the comets might have come from around Jupiter, because at least one of those has lower deuterium levels. That, however, would not get us any nitrogen, assuming the composition of Europa is typical of icy bodies in the Jovian region. It also presupposes a mass of comets that have essentially disappeared, but not into Jupiter, the obvious gravitational accretional centre.

Option 3 The volatiles were delivered by asteroids. There is some water, nitrogen and carbon in some asteroids, mainly carbonaceous chondrites, but these are in the minority. So, what is being asked for is that there were massive numbers of these asteroids further from the sun that were dislodged and struck Earth, but did not significantly affect the inner asteroids. Unfortunately, there is worse. Earth had to be struck by asteroids with very large amounts of water, large amounts of carbon, and modest amounts of nitrogen. Venus had to be struck by asteroids with modest amounts of water, about the same amount of carbon as Earth, and three times the amount of nitrogen. Mars had to be struck by asteroids with good amounts of water and carbon, but for some reason not as many, despite the fact that all asteroid striking anything have to cross Mars’ path, and seemingly very little nitrogen, although as later posts will show, there is ambiguity here. In other words, there were three different sorts of asteroids, and they each separately struck a different planet. Now, if you believe that, there is another problem. Isotope analysis of other elements (Drake, M. J., Righter, K., 2002. Determining the composition of the Earth. Nature 416: 39-44.) shows us that the rocks in asteroids can only have had a very minor part to play in Earth’s accretion. There are other compositional problems as well, and the overall conclusion is that the volatiles did not come from asteroids either.

Option 4 The volatiles were adsorbed onto dust in the accretion disk, and as the planet accreted, the dust got hotter, turned into rock, and the gases came out of volcanoes to form the atmosphere. Actually, there are two premises here. The first is that the gases were trapped on dust, and the second one is that the gases were emitted from volcanoes (or fumaroles). The first premise is wrong, because nitrogen, carbon monoxide and neon are each adsorbed on silicate dust to roughly the same degree, and so would end up being present in roughly the same amounts. Compared with nitrogen, Earth has roughly a hundred times more carbon, and about five orders of magnitude less neon. That is not the source of the atmosphere. On the other hand, there is good evidence that the volatiles on Mars came from volcanoes. Thus the large “normal” river systems and remains of lakes, etc, are of about the same age as the volcanic activity. For Mars, at least, it seems that for about half a billion years Mars had no atmosphere of significance, then volcanic activity started and there were rivers flowing. This happened on and off for a few hundred million years, then everything started to freeze out. The catastrophic flows actually occurred almost a billion years after the main rivers stopped flowing.

So, the problem now is, we have eliminated just about every possible physical mechanism for getting the gases there. Obviously, we have missed something in the above analysis, yet the clues are there. But to get further, we have to think about how rocky planets could form in the first place, and that will be material for a further Monday post. To get to an explanation for the catastrophic floods, or how the materials for life emerged, we have to go to a number of other places first.

We seem to have candidates

Because I am a foreigner, maybe I should not comment on the current US presidential election cycle, but I can’t help myself. After all, even if I am not an American, this is of significant interest to the rest of the world because the US is such an important country. So, what do we see happening? From my point of view the result seems almost bizarre: the presidential fight will most likely be between two candidates who are basically unliked. There have been varying attacks on Hillary Clinton for the last four years, and one cannot help but suspect that a lot of these were orchestrated by the Republicans. However, just to make this a sporting contest, it would seem, the Republicans have latched onto a candidate that even they really don’t like, and to make matters worse, that candidate has based his program so far on seriously annoying at least 70% of the potential voting public.

What I would have thought would be the most unlikely candidate, Sanders, now appears not to have a chance at nomination, but he ploughs on. He might complain about the party machine, but as far as I am aware, if the super delegates were removed, he would still lose. Notwithstanding that, he has done something quite remarkable, at least in my eyes: he has stood as a socialist (well, he calls himself one, although some Europeans would probably think he was more a slightly right wing social democrat) and nearly succeeded. That goes against what used to be considered the American way of life.

From my point of view, policy now becomes interesting. Hillary Clinton seems to represent the establishment, more or less, but it seems the majority of the electorate is tiring of the establishment. The top of the establishment is doing very well for itself, but at the expense of many at the lower end of the social structures. The American dream used to be that America was a land of opportunity, and even if you were at the bottom of the heap, you could fight your way up. There were ways to the top. They may not have been easy to find, but they were there. And even if you could not get to the top, you could get somewhere very comfortable, if you made the effort. There still are ways to the top, but they are becoming harder to find, and much harder for those below average, which means half the population. Worse, thanks to the exporting of jobs, the middle has been hollowed out, and there are far fewer ways to get comfortable. Sanders campaigned, as far as I could see, to give those at the bottom and possibly the middle a better deal. Many commentators thought his plans would not work, but they still thought he was worth supporting. What I found interesting was that it was the young who were supporting the oldest candidate. That tends to indicate the young are unimpressed with the establishment. Maybe they always were, but to this extent? The question now is, will those young support Hillary? Will Hillary bring herself to adopt some of Sanders’ policies, and if so, will she gain by doing so?

Meanwhile, on the other side, Trump seems to have made an art form out of insulting everyone, and has been very light on policy, apart from wanting to build the modest wall of America, and to keep Muslims out. His verbal lashing out by calling a judge a Mexican seemed bizarre, especially since the judge came from Indiana, or is Trump intending to give Mexico some more states?

Which raises the question, how should people who wish to rule be elected? This problem goes all the way back to Plato, who was opposed to democracy and opted for an enlightened prince. That, of course, leaves aside the problem of how to find one, and what to do if the enlightened one turns out not to be and you get the anything but benign dictator? The advantages of the Republic form of government we have include the option to turf out the disasters after a given period of time, coupled with the fact that if the government is really bad, an awful lot of politicians will be cleaned out too. Their self-interest tends to minimize a disastrous leader.

That may seem to be ideal, but I am far from convinced it is. An unfortunate problem has arisen in many parts of the world: too many politicians have opted for this as a career early on, and as a consequence, have a lot of experience at being a politician, but not much at anything else, so their chances of really understanding a problem they have to make decisions on is slim. What we have done is to find a method to get the politicians into power who are the best at winning elections, but not necessarily being any good at anything else. We appoint people to the most responsible of all jobs, the running of our country, by ignoring whether any of the skill sets required to do the job are actually present.

So, what will happen? Your guess is probably better than mine, however my guess is not encouraging. So far there has been a lot of mud thrown, and there is likely to be a lot of general disgruntlement at the end of November. Unless a very serious healing process takes place, I suspect whoever wins may find the White House something of a poisoned chalice.