How Science Has Operated

The October 10 edition of the magazine Palladium published an item called The Transformations of Science. The following includes some of my thoughts on what the article stated, relating to the issue of trust in science. In 1660 the Royal Society was formed, and it adopted the motto Nullius in verba, which means take no one’s word for it. This was their version of how science should be carried out: check everything. The article notes that Thomas Hobbes objected, maybe because he was not a member of the Royal Society. Hobbes pointed out that not everyone could make such observations and stated claims should be derived mathematically from axioms. This raised a problem: who was supposed to make the relevant observations and who was supposed to rely on whom? Unstated was another issue: do we require procedures derived from axioms that allows calculations to get the results we need (the epistemic approach), or do we try to understand what is going on (the ontological approach)? This hounds modern quantum mechanics.

None of this produced benefit, however. Back then, science was a curiosity. There was public interest, particularly when the Leyden jar was developed. Apparently, a large number of people would join hands and one would touch the jar, when they would all get an electrical shock. Michael Faraday gave public demonstrations that filled halls and showed phenomena that probably seemed like magic. However, it would not be long before science got too complicated. People might come to see Faraday do some amazing things with electricity, but they would hardly come to watch the manipulation of Maxwell’s partial differential equations.

Nullius in verba implies everything should be re-examined and re-verified. That makes little sense. How many times do you have to check the melting point of benzoic acid? Accordingly, what we have now is settled science. This is the authoritative version, but that brings its own problems. Authority is a powerful resource, and before long politicians saw a point of using it to justify their decisions, and to maintain this, the state supplied money to keep it going. Science made an impact in WW I, and a hugely more important role in WW II. The provision of electrical appliances following Faraday and Maxwell, and the more startling appliances that depend on quantum mechanics, together with the development of modern medicine, have made us dependent on science. The problem with this is how is it “settled”? Giordano Bruno was burnt at the stake for daring to go against “settled” science. He supported Copernicus’ heliocentric theory, and how could anyone reject the settled conclusion that everything went around Earth? Fortunately for heretics like me, we have now developed a different approach: ignore the heresy.

Sometimes science is either not settled or does not give clean answers. The recent issue of mask-wearing is indicative. Politicians had to make decisions based on limited information. From the scientific view, if we restrict our thoughts solely to the virus, mask wearing cannot do harm (i.e. make viruses more likely to infect) as long as people handle the masks properly, whereas they might do good. They were, however, very unpopular and many people objected because the state made them do something. The reputation of science was also damaged.

We have a similar problem with climate change and the effect of greenhouse gases. The problem is the epistemic approach. You hear comments that the climate varies and the variations are due to “natural causes”. Worse, the population has expanded dramatically based on the availability of cheap energy, and in doing so it has locked in the need for it, at least in the short term. To stop burning fossil fuels today would lead to serious economic problems tomorrow; failure to stop today will lead to catastrophic economic problems for our great grandchildren. But politicians never think past the next election, or at least not sufficiently well to act on those thoughts. The scientists lose face because they cannot predict exactly what will happen. The population, however, cannot understand the concept of partial differential equations and cannot understand the consequences of a number of different effects that sometimes reinforce or sometimes cancel. The so-called Southern Oscillation is an example. The scientists know fine well what the causes are, but putting numbers to them and combining them well into the future is a probabilistic effort.

So, what does this article recommend? The first is a reconciliation between exploratory and authoritative elements. That requires changes in scientific practice and public comprehension. It argues some fields should disclaim authority partly or completely. It even suggests some scientific journals should ban authoritative articles. It suggests some parts of science should be shed off and rarely interact with other parts, thereby preventing premature consensus. It also suggests funding has to be restructured, with exploratory science removed from central funding, where authority and settled science resides.

So, what do I think this means. Feel free to offer your thoughts. I shall add more thoughts in a later post, mainly on the issue of “settled science”.

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Success! Defence Against Asteroids

Most people will know that about 64 million years ago an asteroid with a diameter of about 10 km struck the Yucatán peninsula and exterminated the dinosaurs, or at least did great damage to them from which they never recovered. The shock-wave probably also initiated the formation of the Deccan Traps, and the unpleasant emission of poisonous gases which would finish off any remaining dinosaurs. The crater is 180 km wide and 20 km deep. That was a very sizeable excavation. Rather wisely, we would like to avoid a similar fate, and the question is, can we do anything about it? NASA thinks so, and they carried out an experiment.

I would be extremely surprised if, five years ago, anyone reading this had heard of Dimorphos. Dimorphos is a small asteroid with dimensions about those of the original Colosseum, i.e.  before vandals, like the Catholic Church took stones away to make their own buildings. By now you will be aware that Dimorphos orbits another larger asteroid called Didymos. What NASA has done was to send a metallic object of dimensions 1.8 x 1.9 x 2.6 meters, of mass 570 kg, and velocity 22,530 km/hr to crash into Dimorphos to slightly slow its orbital speed, which would change its orbital parameters. It would also change then orbital characteristics of the two around the sun. Dimorphos has a “diameter” of about 160 m., Didymos about 780 m. Neither are spherical hence the quotation marks.

This explains why NASA selected Dimorphos for the collision. First, it is not that far from Earth, while the two on their current orbits will not collide with Earth on their current orbits. Being close to Earth, at least when their orbits bring them close, lowers the energy requirement to send an object there. It is also easier to observe what happens hence more accurately determine the consequences. The second reason is that Dimorphos is reasonably small and so if a collision changes its dynamics, we shall be able to see by how much. At first sight you might say that conservation of momentum makes that obvious, but it is actually more difficult to know because it depends on what takes the momentum away after the collision. If it is perfectly inelastic, the object gets “absorbed” by the target which stays intact, then we simply add its relative momentum to that of the target. However, real collisions are seldom inelastic, and it would have been considered important to determine how inelastic. A further possibility is that the asteroid could fragment, and send bits in different directions. Think of Newton’s cradle. You hit one end and the ball stops but another flies off from the other end, and the total stationary mass is the same. NASA would wish to know how well the asteroid held together. A final reason for selecting Dimorphos would be that by being tethered gravitationally to Didymos, it could not go flying off is some unfortunate direction, and eventually collide with Earth. It is interesting that the change of momentum is shared between the two bodies through their gravitational interaction.

So, what happened, apart from the collision. There was another space craft trailing behind: the Italian LICIACube (don’t you like these names? It is an acronym for “Light Italian Cubesat for Imaging Asteroids”, and I guess they were so proud of the shape they had to have “cube” twice!). Anyway, this took a photograph before and after impact, and after impact Dimorphos was surrounded by a shower of material flung up from the asteroid. You could no longer see the asteroid for the cloud of debris. Of course Dimorphos survived, and the good news is we now know that the periodic time of Dimorphos around Didymos has been shortened by 32 minutes. That is a genuine success. (Apparently, initially a change  by as little as 73 seconds would have been considered a success!) Also, very importantly, Dimorphos held together. It is not a loosely bound rubble pile, which would be no surprise to anyone who has read my ebook “Planetary Formation and Biogenesis”.

This raises another interesting fact. The impact slowed Dimorphos down relative to Didymos, so Dimorphos fell closer to Didymos, and sped up. That is why the periodic time was shortened. The speeding up is because when you lower the potential energy, you bring the objects closer together and thus lower the total energy, but this equals the kinetic energy except the kinetic energy has the opposite sign, so it increases. (It also shortens the path length, which also lowers the periodic time..)

The reason for all this is to develop a planetary protection system. If you know that an asteroid is going to strike Earth, what do you do? The obvious answer is to divert it, but how? The answer NASA has tested is to strike it with a fast-moving small object. But, you might protest, an object like that would not make much of a change in the orbit of a dinosaur killer. The point is, it doesn’t have to. Take a laser light and point it at a screen. Now, give it a gentle nudge so it changes where it impacts. If the screen as a few centimeters away the lateral shift is trivial, but if the screen is a kilometer away, the lateral shift is now significant, and in fact the lateral shift is proportional to the distance. The idea is that if you can catch the asteroid far enough away, the asteroid won’t strike Earth because the lateral shift will be sufficient.

You might protest that asteroids do not travel in a straight line. No, they don’t, and in fact have trajectories that are part of an ellipse. However, this is still a line, and will still shift laterally. The mathematics are a bit more complicated because the asteroid will return to somewhere fairly close to where it was impacted, but if you can nudge it sufficiently far away from Earth it will miss. How big a nudge? That is the question about which this collision was designed to provide us with clues.

If something like Dimorphos struck Earth it would produce a crater about 1.6 km wide and 370 m deep, while the pressure wave would knock buildings over tens of km away. If it struck the centre of London, windows would break all over South-East England. There would be no survivors in central London, but maybe some on the outskirts. This small asteroid would be the equivalent a good-sized hydrogen bomb, and, as you should realize, a much larger asteroid would do far more damage. If you are interested in further information, I have some data and a discussion of such collisions in my ebook noted above.

Did Mars Have an Ocean?

It is now generally recognized that Mars has had fluid flows, and a number of riverbeds, lake beds, etc have been identified, but there are also maps on the web of a proposed Northern Ocean. It has also been proposed that there has been polar wander, and this Northern Ocean was more an equatorial one when it was there about 3.6 billion years ago. The following is a partial summary from my ebook “Planetary Formation and Biogenesis”, where references to scientific papers citing the information can be found.

Various options include: (with bracketed volumes of water in cubic kilometre): a northern lake (54,000), the Utopia basin, (if interconnected, each with 1,000,000), filled to a possibly identified ‘shoreline’ (14,000,000), to a massive northern hemisphere ocean (96,000,000). Of particular interest is that the massive channels (apart from two that run into Hellas) all terminate within an elevation of 60 m of this putative shoreline.

A Northern Ocean would seem to require an average temperature greater than 273 degrees K, but the faint sun (the sun is slowly heating and three and a half billion years ago, when it is assumed water flowed, it had only about two thirds its current output) and an atmosphere restricted to CO₂/H₂O leads in most simulations to mean global temperatures of approximately 225 degrees K. There is the possibility of local variations, however, and one calculation claimed that if global temperatures were thirty degrees higher, local conditions could permit Hellas to pond if the subsurface contained sufficient water, and with sufficient water, the northern ocean would be possible and for maybe a few hundred years be ice free. A different model based on simulations, assuming a 1 bar CO₂ atmosphere with a further 0.1 bar of hydrogen, considered that a northern ocean would be stable up to about three billion years. There is quite an industry of such calculations and it is hard to make out how valid they are, but this one seems not to be appropriate. If we had one bar pressure of carbon dioxide for such a long time there would be massive carbonate deposits, such as lime, or iron carbonates, and these are not found in the required volumes. Also, the gravity of Earth is insufficient to hold that amount of hydrogen and Mars has only 40% of Earth’s gravity. This cannot be correct.

This northern ocean has been criticized on the basis that the shoreline itself is not at a constant gravitational potential, and variations of as much as 1.8 km in altitude are found. This should falsify the concept, except that because this proposed ocean is close to the Tharsis volcanic area, the deformation of forming these massive volcanoes could account for the differences. The magma that is ejected had to come from somewhere, and where it migrated from would lead to an overall lowering of the surface there, while where it migrated to would rise.

Support for a northern sea comes from the Acidalia region, where resurfacing appears to have occurred in pulses, finishing somewhere around 3.65 Gy BP.  Accumulation of bright material from subsequent impacts and flow-like mantling was consistent with a water/mud northern ocean. If water flows through rock to end in a sea, certain water-soluble elements are concentrated in the sea, and gamma ray spectra indicates that this northern ocean is consistent with enhanced levels of potassium and possibly thorium and iron. There may, however, be other reasons for this. While none of this is conclusive, a problem with such data is that we only see the top few centimeters and better evidence could be buried in dust.

Further possible support comes from the Zhurong rover that landed in Utopia Planitia (Liu, Y., and 11 others. 2022. Zhurong reveals recent aqueous activities in Utopia Planitia, Mars. Science Adv., 8: eabn8555). Duricrusts formed cliffs perched through loose soil, which requires a substantial amount of water, and also avoids the “buried in dust” problem. The authors considered these were formed through regolith undergoing cementation through rising or infiltration of briny groundwater. The salt cements precipitate from groundwater in a zone where active evaporation and accumulation can occur. Further, it is suggested thus has occurred relatively recently. On the other hand, ground water seepage might also do it, although the water has to be salty.

All of which is interesting, but the question remains: why was the water liquid? 225 degrees K is about fifty degrees below water’s freezing point. Second, because the sun has been putting out more heat, why is the water not flowing now? Or, alternatively, as generally believed, why did it flow for a brief period than stop? My answer, somewhat unsurprisingly since I am a chemist, is that it depends on chemistry. The gases had to be emitted from below the surface, such as from volcanoes or fumaroles. The gases could not have been adsorbed there as the planet accreted otherwise there would be comparable amounts of neon as to nitrogen on the rocky planets, and there is not. That implies the gases were accreted as chemical compounds; neon was not because it has no chemistry. When the accreted compounds are broken down with water, ammonia forms. Ammonia dissolves very rapidly in water, or ice, and liquefies it down to about 195 degrees K, which is well within the proposed range stated above. However, ammonia is decomposed slowly by sunlight, to form nitrogen, but it will be protected when dissolved in water. The one sample of seawater from about 3.2 billion years ago is consistent with Earth having about 10% of its nitrogen still as ammonia. However, on Mars ammonia would slowly react with carbon dioxide being formed, and end up as solids buried under the dust.

Does this help a northers sea? If this is correct, there should be substantial deposits of nitrogen rich solids below the dust. If we went there to dig, we would find out.

Radiation Protection on Mars

The settlement of Mars is a popular science fiction staple. I have written some “Mars novels” myself. One criticism of settling Mars is that the planet does not have magnetic field to deflect radiation, so what is the situation? In my ebook “Red Gold” I suggested a magnetic field be generated by a superconductor placed between Mars and the sun, specifically at the first Lagrange point so it would be there continuously. That would divert charged particles in the solar wind. However, suppose you do not do that, what are the options. An account has been written on May 27, 2022 and is at arXiv:2205.13786.

There are two sources of radiation. The first is from the sun and consist mainly of protons, helium nuclei (5 – 8%) and heavier nuclei (~1%). These arrive with energies ranging from some keV to hundreds of MeV. Very occasionally they go to even higher energies, and their intensity varies with the solar cycle. The other source are the cosmic rays. These are accelerated by supernova shocks and interstellar magnetic fields, and appear to come evenly from all directions. They have similar composition to the solar radiation, but they arrive with far higher energies, their average being in the GeV range, and of particular hazard are the high-charge ions, thus there may be particles up to iron that are stripped of their electrons and are travelling through space near the speed of light. It is this high energy and high charge that makes them so dangerous.

The first defence Mars offers is bulk. A person standing on the Martian surface, particularly in a crater, receives less than half what they would receive in space, and that applies to cosmic rays. None of these have energy anywhere nearly enough to go through a planet. The atmosphere, while thin, offers some protection, and will remove protons with less than 150 MeV energy, and possibly more if in a deep enough crater (which is partly why in “Red Gold” I had my settlement near the bottom of Hellas Planitia, the deepest part of Mars.) Accordingly, the major chronic hazard is cosmic radiation, but a sudden strike by a major solar event is also lethal.

There are two types of shielding. The first is active, the use of magnetic or plasma shields, but currently these are theoretical, such as my suggested L1 superconducting magnetic field generator. The second is passive, which is to place matter between the person and the source. At present we are reliant on passive measures. The better materials for stopping such charged particles are those with a high number density of atoms with many electrons per unit mass, which ends up meaning elements of low atomic number. Materials rich in hydrogen such as water or polyethylene perform well, although nothing practical can totally eliminate cosmic radiation.

For settlers on Mars, interactions with the atmosphere lead to neutrons and gamma rays being dominant. Terrain offers protection, thus being adjacent to a cliff will halve the exposure compared with open terrain. The water in regolith will greatly attenuate neutrons with less kinetic energy than 10 MeV. Liquid hydrogen is probably the best, but its extremely low temperature probably makes it impractical. Organic plastics work well; aluminium, which is used in spacecraft, is somewhat less satisfactory, but οn Μars the regolith is probably optimal, because it is already there and hence is cheap. On the other hand, it has to be bound by something, otherwise the wind will blow it away. The article suggests making bricks from regolith. The simplest protection is to live in caves. However, there may be a shortage of caves. People talk about lava tubes, but much of the volcanism on Mars has been around very large volcanoes, or older ones that erupted more in a pyroclastic fashion. They will be short on caves, while settlers are more likely to head for craters, which are not the obvious place to find caves, although rapidly exiting steam might leave one. One place where there might be caves is the Margaritifer Chaos, where there  are signs of massive water outflows from a very small source.

However, living underground does not help plant growth, and the idea of having huge caverns with lights would require a huge investment in lights. It should be easy to make glass that will be opaque to UV radiation and will offer tolerable radiation protection. Silicate uses light atoms and should compare favourably with aluminium. Further, the danger of cosmic rays is largely long-term health; plants for food are not long-lived. One of the main problems for people settling on Mars is the cost and mass of what they have to take with them. Making bricks from regolith is great because regolith is there. The cost of lifting stuff up from Earth and taking it to Mars is huge, so as much as possible has to be made there. That is why lights for the underground growing of food would be very expensive. But the making of any habitat or plant growing area on the surface requires sealing to prevent gas pressure escaping. In my “Red Gold” I suggest one of the very first things that has to be learned is how to make a cement from Martian materials. The ability to make concrete is the first requirement to make the footers of “glass-houses” to grow plants, and cement is necessary to put bricks together. There is an awful lot of detail that has to be addressed because once settlers get there, if they haven’t got something, they cannot go to the corner store and get it.

Belief in Science

I recently read something from a libertarian who accused people who “believe in science” as followers of a religion. The first point was, how can you so believe when you find well-credentialled scientists on both sides of an issue? The writer claimed that certain people may prefer people do not know this, but dissenting experts exist on many scientific questions that some pronounce as settled by a consensus. It claims credentialled maverick are often maligned as having been corrupted by industry, while scientists who view the established position are pure and incorruptible. So what do you think of that?

One comment lies in “well-credentialled” and “both sides of the issue”. By the time I started science in earnest, so to speak, Sir Richard Doll had produced a study showing heavy smoking greatly increased the risk of lung cancer. At the time, epidemiology was a “fringe” part of medicine but the statistics showed the truth. Naturally, there were people who questioned it, but I recall a review that showed that cigarette smoke contained a large number of chemicals that could be called carcinogens. One, 3,4-benzopyrene, was so active it guaranteed a cancer if a smear was applied to a certain strain of mice. Yes, they were particularly susceptible, but the point was obvious. Cigarette smoke contains a number of carcinogenic chemicals. Yet for years papers were produced that showed cigarette smoke was “harmless” and something else must be doing it. These were published in fringe journals and while the authors had credentials, they were being paid by the tobacco industry. So much for “both sides of the issue”.

A major criticism that comes to my mind is that the author does not understand what he is talking about. Science is not a collection of facts; it is a methodology for attempting to obtain the truth. Like any other activity, it does not always work well, but in principle you do not accept a statement based on the reputation of the speaker; that is the logic fallacy ad verecundiam. Unfortunately, what actually happens is so many are just plain lazy so they do not seek to check but rather accept it. Of course, if it is not important to you the consensus usually makes a lot of sense because you have not examined the details. Further, you accept it because you are only marginally interested. If someone says that a vaccine has passed a clinical trial in which x thousand people took part, there were no adverse effects and the vaccine worked, I take their word. The alternative is to check everything yourself, but you know that a procedure is in place where independent people have checked the statements, so I accept they are true. Science works by recording what we know and building on it. If there was a huge conspiracy to hide some real problems with a vaccine, the conspirators would eventually be found out, and an extended length of time would be spent in a rather uncomfortable cell.

Another criticism was that the “truth” comes down from a set of anointed scientists, and dissenters can be ignored because they are outside the group that matters. There is an element of truth in this. The anointed always get funding, and they get to peer review other funding applications. Dissent from the anointed means it is far more difficult to get funding. Further, the number of citations and publications you get means more funding. This leads to gaming the system, but such gaming cannot work with a dissenter. Sometimes, up to fifty scientists may agree to be authors on a number of papers (If you have fifty, they should produce fifty times the output of one.) But nobody counts the degree of share, and worse, they can keep citing all the papers within the set when one is being written, so automatically the number of citations jumps. Nobody notices they are self-citations or looks to see if they are relevant. That may seem unfair to others, but with money at stake, scientists also do what they can. This funding anomaly does lead to a group consensus.

Another example lies in climate change. Whether there is consensus is irrelevant; the question is, is there a definitive observation? I concede that initially I was suspicious, largely because there was a lot of modelling but not many facts. The theory was known, but the models ignored too many variables, and nothing seemed to have happened to the climate. The theory suggested there was an effect, but at first there was not much evidence for it. Then the evidence of warmer times started to come, but against that is climate has always changed. What was needed was a definitive set of measurements, and eventually they came (Lyman, J. M. and 7 others, 2010. Nature 465: 334-337.) What this showed was between 1993 and 2008 there was been an increase in the heat power delivered to the oceans of 0.64 w.m^-2. That may not seem to be much, but multiply that across the area of oceans and you will see the planet is getting a very substantial net power input over a long period of time. We are cooking ourselves, but like the proverbial frog, we seem not to notice enough to do much about it.

One final comment. I wrote a chapter on climate change in my first ebook, which was about how to form theories, and which not only included the reasons why we should recognize the effect is real, but also I listed some previous technologies that could go some way towards reducing our dependencies on fossil fuels. These were all published or recorded in various archives, and one of the interesting things about this is that none of the recommended technologies have been proposed to be used. It is almost as if work done in the 1970-80s might as well not have been carried out. So what seemed to be “state of the art” then is now forgotten. There are problems in dealing with scientific issues and getting value from them, but group consensus is only temporary, and anything that can be forgotten probably will be. You don’t get science funding resurrecting the wheel, but you get somewhere. The question is, do we really want to get somewhere?

How Did We Escape the RNA World?

In my ebook “Planetary Formation and Biogenesis” I argue that life had to start with nucleic acids because only nucleic acids can provide a plausible mechanism for reproduction, and, of course, that is exactly what they do now – they reproduce. The RNA world may not qualify as life as more is required, but if this step is not achieved there can be no life. The first reproducing agent had to be RNA because ribose is the only sugar that occurs at least partially in a furanose form. (The furanose is a five-membered ring; the pyranose is a six-membered ring and is generally more stable.) Why do we need the furanose? In my ebook I show various reasons, but the main one is that the only plausible experiment so far to show phosphate esters could have formed naturally lead to AMP and ATP. While the ribose is only about 20% furanose, NO pyranose formed phosphate esters.

Later, DNA was used primarily for reproduction for a very simple reason: it uses 2-deoxyribose. The removal of the 2-hydroxyl from ribose makes the polymer several orders of magnitude more stable. So why did this not be part of the starting mix? Leaving aside the fact we do not really know how to get 2-deoxyribose in any synthesis that could reasonably have happened in some sort of pond without help (complicated laboratory chemical syntheses are out!) there is a more important reason: at the beginning high accuracy in reproduction is undesirable. The first such life forms (i.e. things that reproduce) are not going to be very useful. They were chosen at random and should have all sorts of defects. What we need is rapid evolution, and we are more likely to get that from something that mutates more often. Further, RNA can act as a catalyst, which speeds up- everything.

Bonfio (Nature, 605, p231-2) raises two questions. The first borders on silly: why did proteins as enzymes replace most of RNA catalytic activity? The short answer is they are immensely better. They speed things up by factors of billions, and they are stable, so they can be reused over and over again. So why did they not arise immediately? Consider the enzyme that degrades protein; it has 315 properly sequenced amino acids. If we limit ourselves to 20 different ones, and allow for the initial ones being either left- or right-handed, except for glycine, the probability of random selection is 2 in 39^315. That is, 39 multiplied by itself 315 times. To put that in perspective, there are just 10^85 elementary particles in the visible universe. It was simply impossible. But that raises the second, and extremely interesting question: how could ordered protein selection emerge with such horrendous odds against?

What happens now is that messenger RNA has three nucleotide sequences “recognized” and “transfers” this information to transfer RNA which selects an amino acid and attaches it to the growing chain, then goes back to the messenger RNA to get the next selection information. That is grossly oversimplified, but you might get the picture. The question is, how could this emerge? The answer appears to include non—canonical nucleotides. RNA comprises mainly adenine, guanine, cytosine and uracil, and these are the “information” holders, but there are some additional entities present. One is adenosine with a threonylcarbamoyl group attached. The details are not important at this level – merely that there is something additional there. The important fact is there is no phosphate linkage so this is not in the chain. At first sight, these are bad because they block chain formation. Thus for every time this hydrogen-bonded to a uracil, say, it would block the chain synthesis and stop reproduction. However, it turns out that they may assist peptide synthesis. The non-canonical nucleotide at the terminal point of a RNA strand attracts amino acids. This becomes a donor strand, and it transfers to a similar RNA with a nascent peptide, and we have ordered synthesis. It is claimed that this can be made to happen under conditions that could plausibly occur on Earth. The peptide synthesis involves the generation of a chimeric peptide – RNA intermediate, perhaps the precursor of the modern ribosome. Of course, we are still a long way from an enzyme. However, we have (maybe) located how the peptides could be synthesised in non-random way, and from the RNA we can reproduce a useful sequence, but we are still a very long way from the RNA knowing what sequences will work. The assumption is, they will eventually self-select, based on Darwinian principles, but that would be a slow and very inefficient process. However, as I note in the ebook, the early peptides with no catalytic properties are not necessarily wasted. The most obvious first use would be to incorporate them in the cell wall, which would permit the formation of channels able to bring in fresh nutrients and get rid of excess water pressure. The evolution of life probably a very long time during which much stewing and testing was carried out until something sufficiently robust evolved.

Betelgeuse Dimmed

First, I apologize for the initial bizarre appearance of my last post. For some reason, some computer decided to slice and dice. I have no idea why, or for that matter, how. Hopefully, this post will have better luck.

Some will recall that around October 2019 the red supergiant Betelgeuse dimmed, specifically from magnitude +0.5 down to +1.64. As a variable star, its brightness oscillates, but it had never dimmed like this before, at least within our records. This generated a certain degree of nervousness or excitement because a significant dimming is probably what happens initially before a supernova. There has been no nearby supernova since that of the crab nebula in 1054 AD.

To put a cool spot into perspective, if Betelgeuse replaced the sun, its size is such it would swallow Mars, and its photosphere might almost reach Saturn. Its mass is estimated at least ten times, or possibly up to twenty times, the mass of the sun. Such a variation sparks my interest because when I pointed out that my proposed dependence of characteristic planetary orbital semimajor axes on the cube of the mass of the star ran into trouble because the stellar masses were not known that well I got criticised by an astronomer: they knew the masses to within a few percent. The difference between ten times the sun’s mass and twenty times is more than a few percent. This is a characteristic of science. They can measure stellar masses fairly accurately in double star systems, then they “carry over” the results,

But back to Betelgeuse. Our best guess as to distance is between 500 – 600 light years. Interestingly, we have observed its photosphere, the outer “shell” of the star that is transparent to photons, at least to a degree, and this is non-spherical, presumably due to stellar pulsations that send matter out from the star. The star may seem “stable” but actually its surface (whatever that means) is extremely turbulent. It is also surrounded by something we could call an atmosphere, an envelope of matter about 250 times the size of the star. We don’t really know its size because these asymmetric pulsations can add several astronomical units (the Earth-sun distance) in selected directions.

Anyway, back to the dimming. Two rival theories were produced: one involved the development of a large cooler cell that came to the surface and was dimmer than the rest of Betelgeuse’s surface. The other was the partial obscuring of the star by a dust cloud. Neither proposition really explained the dimming, nor did they explain why Betelgeuse was back to normal by the end of February, 2020. Rather unsurprisingly, the next proposition was that the dimming was caused by both of those effects.

Perhaps the biggest problem because telescopes could only look at the star sone of them however a Japanese weather satellite ended up providing just the data they needed. This was somewhat inadvertent. The weather satellite was in geostationary orbit 35,786 km above the Western Pacific. It was always looking at half of Earth, and always the same half, but the background was also always constant, and in the background was Betelgeuse. The satellite revealed that the star overall cooled by 140 degrees C. This was sufficient to reduce the heating of a nearby gas cloud, and when it cooled, dust condensed and formed obscuring dust. So both theories were right, and even more strangely, both contributed roughly equally to what was called “the Great Dimming”.

It also suggested more was happening to the atmospheric structure of the star before this happened. By looking at the infrared lines, it became apparent that water molecules in the upper atmosphere that would normally create absorption lines in the star’s spectrum suddenly changed to form emission lines. Something had made them become unexpectedly hotter. The current thinking is that a shock-wave from the interior propelled a lot of gas outwards from the star, leading to a cooler surface, while heating the outer atmosphere. That is regarded as the best current explanation. It is possible that there was a similar dimming event in the 1940s, but otherwise we have not noticed much, but possibly it could have occurred but our detection methods may not have been accurate enough. People may not want to get carried away with, “I think it might be dimmer.” Anyway, for the present, no supernova. But one will occur, probably within the next 100,000 years. Keep looking upwards!

Energy Sustainability

Sustainability is the buzzword. Our society must use solar energy, lithium-ion batteries, etc to save the planet, at least that is what they say. But have they done their sums?. Lost in this debate is the fact that many of the technologies use relatively difficult to obtain elements. In a previous post I argued that battery technology was in trouble because there is a shortage of cobalt, required to make the cathode work for a reasonable number of cycles. Others argue that we could obtain sufficient elements. But if we are going to be sustainable, we have to be sustainable for an indefinite length of time, and mining is not sustainable; you can only dig up the ore once. Of course, there are plenty of elements left. There is more gold in the sea than has ever been mined; the problem is that it is too dilute. Similarly, most elements are present in a lump of basalt; just not much of anything useful and it is extremely difficult to get it out. The original copper mines of Cyprus, where even lumps of copper could occasionally be found, are all worked out, at least to the extent that mining is no longer profitable there.

The answer is to recycle, right? Well, according to an article [Charpentier Poncelet, A. et al. Nature Sustain. https://doi.org/10.1038/s41893-022- 00895-8 (2022)] there are troubles. The problem is that even if we recycle, every time we do something we lose some of the metal. Losses here refer to material emitted into the environment, stored in waste-disposal facilities, or diluted in material where the specific characteristics of the elements are no longer required. The authors define a lifetime as the average duration of their use, from mining through to being entirely lost. As with any such definition-dependent study, there will be some points where you disagree.

The first loss for many elements lies in the production state. Quite often it is only economical to obtain one or two elements, and the remaining minor components of the ore disappear in slag. These losses are mainly important for specialty elements. Production losses account for 30% of rare earth metals, 50% for cobalt, 70% for indium, and greater than 95% for arsenic, gallium, germanium, hafnium, selenium and tellurium. So most of those elements critical for certain electronic and photo-electric effects are simply thrown out. We are a wasteful lot.

Manufacturing and use incur very few losses. There are some, but because materials are purified ready for use, pieces that are not immediately used can be remelted and used. There are exceptions. 80% of barium is lost through use; it is used in drilling muds.

The largest losses come from the waste management and recycling stage. Metals undergoing multiple life cycles are still lost this way; it just takes longer to lose them. Recycling losses occur when the metal accumulates in a dust (zinc) or slag(e.g. chromium or vanadium), or get lost in another stream, thus copper is prone to dissolve in an iron stream. Longest lifetimes occur for non-ferrous metals (8 to 76 years) precious metals (4 to 192 years), and ferrous metals (8 to 154 years). The longest lifetimes are for gold and iron.

Now for the problem areas. Lithium has a life-cycle use of 7 years, then it is all gone. But lithium-ion batteries last about this long, which suggests that as yet (if these data are correct) there is very little real recycling of lithium. Elements like gallium and tellurium last less than a year, while indium manages a year. Before you protest that most of the indium goes into swipeable mobile phone screens and mobile phones last longer than a year, at least for some of us, remember that losses occur through being discarded at the mining stage, where the miner/processor can’t be bothered. Of the fifteen metals most lost during mining/processing, thirteen are critical for sustainable energy, such as cobalt (lithium-ion batteries), neodymium (permanent magnets), indium, gallium, germanium, selenium and tellurium (solar cells) and scandium (solid oxide fuel cells). If we look at the recycled content of “new material” lithium is less than 1% as is indium. Gallium and tellurium are seemingly not recycled. Why are they not recycled? Metals that are recycled tend to be like iron, aluminium, the precious metals and copper. It is reasonably easy to find uses for them where purity is not critical. Recycling and purifying most of the others requires technical skill and significant investment. If we think of lithium-ion batteries, the lithium reacts with water, and if it starts burning it is unlikely to be put out. Some items may have over a dozen elements, and some are highly toxic, and not to be in the hands of the amateur. What we see happening is that the “easy” metals are recycled by organizations that are really low-technology organizations. It is not an area attractive to the highly skilled because the economic risk/return is just not worth it, while the less-skilled simply cannot do it safely.

Indigenous Rights in Science

Most readers will have heard of the fights for the rights of indigenous people, but what about people born in the country, whose ancestors have been there for a long period? What rights to they have? Should they have rights to the resources of their own country? You will have heard about animal poaching, where endangered species are smuggled out of the country, and will have a view on that. However, there is a new argument coming in the scientific community, reported in Nature (605, 18 – 19) and it came from an article in the journal Cretaceous Research. The article described Ubirajara jubatus, a 110-million-year-old fossil of a dinosaur that appeared to display the precursors to feathers. The fossil had been collected in Brazil decades earlier but no Brazilian had heard of it. The authors claimed the fossil had been exported with a permit signed by some official, and the skeptic might suspect corruption here.

The publication sparked a revolution. A massive Twitter campaign was launched, and eventually the paper was withdrawn, although how you withdraw a printed paper is another matter. The specimen is in the State Museum of Natural History in Karlesruhe, and apparently the museum is engaged in negotiations to return it.

This practice, called by some colonial palaeontology, has caused a storm across south America. A report that analysed 200 studies published between 1990 and 2021 found that more than half did not involve local researchers, and of the Brazilian fossils used, 88% of them were kept outside Brazil. One of the authors of the Ubirajara paper protested that the study cherry-picked data, and omitted a whole lot of earlier American practices. The author of the report states it picked on starting at 1990 because that was when Brazil introduced laws preventing the export of such fossils, and it would be wrong to criticise a practice that was perfectly legal before then. He also noted it was a curious defence to state that others were doing it, so why not him, despite the law?

Now the South Americans are attempting to persuade scientific journals to act to stop such colonial practices. They noted that none of the 200 studies published an acknowledgement of the permit they should have had to take the specimen out of the country. If you read scientific papers, you often see a remarkable list of acknowledgements, such a X made helpful comments. Acknowledging that you followed the law might seem to be a useful step.

Apparently, this “revolution” had some less that satisfactory behaviour. Members of the public began visibly harassing scientists involved in the Ubirajara research, while the Karlsruhe Museum had to close its Instagram account due to the flood of negative comments.

There followed a spat about how researchers local to where the fossil was found should be involved when the fossil has been in a foreign museum for ages. Our author who protested (above) then continued to protest that this would involve tokenism if they had to include a scientist from the region on the paper. Of course, a way out of that would be to return the fossil. Two other countries particularly affected are the Dominican Republic and Myanmar, both of which have significant fossilized amber, of Jurassic Park fame. What happens next is unclear, although it appears the move to return fossils is growing.

That thought leads to another. Scientific publication involves peer review. It would be interesting to compare the fraction of rejections from third world countries with those from major US/European Universities. Does the address “Harvard” give a serious advantage over some town in Myanmar? Or is it done truly on content?

On a completely different matter, a huge fang of an ichthyosaur has been found from the Swiss alps. From the size of the tooth, the reptile would have measured about 21 meters in length. You might have heard that ichthyosaurs were somewhat vulnerable and only lived in shallow waters. Not this beast. A carnivore the size of a sperm whale would not be a pleasant thing to encounter. However, it died out at the end of the Triassic so no current danger.

Molecular Oxygen in a Comet

There is a pressure, these days, on scientists to be productive. That is fair enough – you don’t want them slacking off in a corner, but a problem arises when this leads to the publication of papers: there are so many of them that nobody can keep up with even a small fraction of them. Worse, many of them do not seem to say much. Up to a point, this has an odd benefit: if you leave a lot unclear, all your associates can publish away and cite you, which has this effect of making you seem more important because funders like to count citations. In short, with obvious exceptions, the less you advance the science, the more important you seem at second level funding. I am going to pick, maybe unfairly, on one paper from Nature Astronomy (https://www.nature.com/articles/s41550-022-01614-1) as an illustration.

One of the most unexpected findings in the coma of comet 67P/Churyumov-Gerasimenko was “a large amount” of molecular oxygen. Something to breathe! Potential space pilots should not get excited; “a large amount” is only large with respect to what they expected, which was none. At the time, this was a surprise to astronomers because molecular oxygen is rather reactive and it is difficult to see why it would be present. Now there is a “breakthrough”: it has been concluded there is not that much oxygen in the comet at all, but this oxygen came from a separate small reservoir. The “clue” came from the molecular oxygen being associated with molecular water when emitted from a warm site. As it got cooler, any oxygen was associated with carbon dioxide or carbon monoxide. Now, you may well wonder what sort of clue that is? My question is, given there is oxygen there, what would you expect? The comet is half water, so when the surface gets warm, it sublimes. When cooler, only gases at that lower temperature get emitted. What is the puzzle?

However, the authors of the paper came to a different conclusion. They decided that there had to be a deep reservoir of oxygen within the comet, and a second reservoir close to the surface that is made of porous frozen water. According to them, oxygen in the core works its way to the surface and gets trapped in the second reservoir. Note that this is an additional proposition to the obvious one that oxygen was trapped in ice near the surface. We knew there was gas trapped in ice that was released with heat, so why postulate multiple reservoirs, other than to get a paper published?

So, where did this oxygen come from? There are two possibilities. The first is it was accreted with the gas from the disk when the comet formed. This is somewhat difficult to accept. Ordinary chemistry suggests that if oxygen molecules were present in the interstellar dust cloud it should react with hydrogen and form water. Maybe that conclusion is somehow wrong, but we can find out. We can estimate the probability by observing the numerous dust clouds from which stars accrete. As far as I am aware, nobody has ever found rich amounts of molecular oxygen in them. The usual practice when you are proposing something unusual is you find some sort of supporting evidence. Seemingly, not this time.

The second possibility is that we know how molecular oxygen could be formed at the surface. High energy photons and solar wind smash water molecules in ice to form hydrogen and hydroxyl radicals. The hydrogen escapes to space but the hydroxyl radicals unite to form hydrogen peroxide or other peroxides or superoxides, which can work their way into the ice. There are a number of other solids that catalyse the degradation of peroxides and superoxides back to oxygen, which would be trapped in the ice, but released when the ice sublimed. So, from the chemist’s point of view there is a fairly ordinary explanation why oxygen might be formed and gather near the surface. From my point of view, Occam’s Razor should apply: you use the simplest explanation unless there is good evidence. I do not see any evidence about the interior of the comet.

Does it matter? From my point of view when someone with some sort of authority/standing says something like this, there is the danger that the next paper will say “X established that . . “  and it becomes almost a gospel. This is especially so when the assertion cannot be easily challenged with evidence as you cannot get inside that comet. Which gives the perverse realization that you need strong evidence to challenge an assertion, but maybe no evidence at all to assert it in the first place. Weird?