There is a time for everything and a season for every activity under the heavens … (Ecclesiastes 3, v1)
He has made everything beautiful in its time. He has also set eternity in the human heart …
(Ecclesiastes 3, v11)
John writes …
I quoted these verses at the front of my PhD thesis many years ago. They sandwich a passage in which ‘[there is] a time to …’ as used in the folk song ‘Turn, turn, turn.’ Many people have some familiarity with at least part of the passage without knowing that it comes from the Bible. The version of ‘Turn, turn, turn’ recorded in 1966 by Pete Seeger was recently played on BBC radio. It was obvious that the programme’s presenter was one of those who do not know that the words are Biblical – he ascribed them to the anti-war movement of the 1960s.
In recent days I have gone back to these verses and again thought about them in relation to the creation. The existence of seasons results from the way our planet is set up but it doesn’t have to be that way. Planets without seasons are perfectly good planets. So, as I enjoy the lovely autumn colours and indeed understand the underlying biology, I thank God that He has made everything beautiful in its time.
But that also challenges me. Autumns are getting warmer; the biological changes, except those driven entirely by day-length, are occurring later. Ecosystems are changing because the climate is changing; this is a matter for prayer and urgent action.
All pictures are credited to the author.
Graham writes …
In October’s post, John discussed the winner of the Nobel Prize of Physiology and Medicine, and this month I’d like to say something about the work of the winners of the Physics Prize, and the extraordinary things it says about the nature of reality. There were three winners, Alain Aspect, John Clauser and Anton Zeilinger, and broadly speaking they earned the prize for their work on the topic of quantum entanglement. So what is quantum entanglement, and why is it important? I’d like to say something about this concept, hopefully in language that is accessible to non-physicists
As you may know, prior to the 1900s, the laws devised by Isaac Newton reigned supreme. It is also fair to say that for many engineering and science applications today, Newton’s theory still works. This classical theory is elegant, compact and powerful, and is still part of the education of a young science student today. One of the main aspects of Newton’s physics is what it says about the nature of reality. Put simply, if you tell me how the world is now, then the theory will tell you precisely how the world will be tomorrow (or indeed yesterday). In other words, if the positions and velocity of all the particles in the Universe were known at a particular time, then in principle Newton will be able to determine the state of all the particles at another time. This total determinism is a defining facet of Newtonian physics.
However, in the early years of the 20th Century, the comforting edifice of classical physics collapsed under the onslaught of a new theory. Physicists investigating the world of the very small – the realm of molecules, atoms and elementary particles – found that Newton’s laws no longer worked. A huge developmental effort on the part of scientists, such as Einstein, Planck, Bohr, Heisenberg, Schrödinger and others, ultimately led to an understanding of the micro-world through the elaboration of a new theory called quantum mechanics (QM). However, it was soon realised that the total determinism of classical physics was lost. The nature of reality had changed dramatically. In the new theoretical regime, if you tell me how the world is now, QM will tell you the probability that the world is in this state or in that.
Einstein was one of the principal founders of the theory of QM, but it is well known that over time he came to reject it as a complete description of the Universe. Much has been made of Einstein’s resistance to QM, summed up by his memorable quote that “God does not play dice with the world”. However, Einstein could not deny that QM probabilities provided a spectacularly accurate prediction of what was going on in the microworld. Instead, he believed that QM was a provisional theory that would ultimately be replaced by a deeper understanding, and the new theory would eliminate the probabilistic attributes. He could not come to terms with the idea that probabilities defined the Universe, and felt there must be an underlying reality that QM did not describe. He believed that this deeper understanding would emerge from a new theory involving what has become known as ‘hidden variables’. On a personal note, I have to say I have great sympathy with Einstein’s view. As an undergraduate, with a very immature appreciation of QM, I too could never get to grips with it from the point of view of its interpretation of how the Universe works. This is one of the reasons why I studied general relativity – Einstein’s gravity theory – at doctorate level, which is inherently a classical theory.
Getting back to the discussion, Einstein strived to find his ultimate theory until the end of his life. Along the way, he was always attempting to find contradictions and weaknesses in QM. If he believed that he had found something, he would throw out a challenge to his circle of eminent ‘QM believers’. This stimulating discourse continued for many years. Then in 1935, with the publication of a paper with coauthors Podolsky and Rosen, Einstein believed he had found the ultimate weakness in QM in a property referred to as quantum entanglement (QE). This publication became known as the ‘EPR paper’. In broad terms, QE can be summarised along the lines of – if two objects interact and then separate, a subsequent measurement of one of them revealing some attribute would have an instantaneous influence on the other object regardless of their distance apart.
You might ask, why does this have such a profound impact on our understanding of reality? To grasp this, we need to discuss in a little more detail what this means when we consider quantum objects, like subatomic particles, and their quantum qualities, such a quantum spin. We have discussed the enigma of quantum spin before (see the March 2022 blog post). If we measure the quantum spin of a particle about a particular axis, then the result always reveals that it is spinning either anti-clockwise or clockwise (as seen from above), with the same magnitude. The former state is referred to ‘spin up’ and the latter ‘spin down’. There are just two outcomes, and this is a consequence of the quantised nature of the particle’s angular momentum (or rotation). As I have said before – nobody said quantum spin was an intuitive concept! It is possible to produce two particles in an interaction in the laboratory such that they zoom off in opposite directions, one in a spin up state and the other in a spin down state (for example). In the process of their interaction the two particles have become entangled, and we can measure their spin in detectors placed at each end of the laboratory.
Another part of this story is understanding the nature of measurement in QM. In the example we have chosen above, the conventional interpretation of QM says that the particle’s spin state is only revealed when a measurement takes place. Prior to this moment the particle is regarded as being in a state in which it is neither spin up nor spin down, but in a fuzzy state of being both. The probability of one or other state is defined by something called the wave function, and a collapse of the wave function occurs the moment a measurement is made, to reveal the actual spin state of the particle. This process is something of a mystery, and is still not fully understood. However, that is another story. For interested readers, please Google ‘the collapse of the wave function’ for more detail.
So, in our discussion, we have two ways of interpreting our experiment. That of QM which says that the spin state of the particle is only revealed when a measurement is made, and that of Einstein who believed in an underlying reality in which the spin state has a definite value throughout. If you think about the two entangled particles created in the lab, discussed above, then QE only presents us with an issue if QM is correct and Einstein is wrong. In this case, the measurement of the spin of one particle reveals its value (up or down), and an instantaneous causal influence will reveal the state of the other (the opposite value), even if the two particles are light years apart.
Einstein called this "strange spooky action at a distance”, and it troubled him deeply, particularly as both his theories of relativity forbid instantaneous propagation of any physical influence. QM could not, in his view, give a full final picture of reality. For years, nobody paid much attention to the EPR paper, mostly because QM worked. The theory was successful in explaining physics experiments and in technology developments. Since no one could think of a way of testing Einstein’s speculation that one day QM would be replaced by a new theory that eliminated probability, the EPR paper was regarded merely as an interesting philosophical diversion.
Einstein died in 1955, and the debate about QE seemed to die with him. However, in 1964 an Irish physicist called John Stuart Bell proved mathematically that there was a way to test Einstein’s view that particles always have definite features, and that there is no spooky connection. Bell’s simple and remarkable incite was that doable experiments could be devised that would determine which of the two views is correct. Put another way, Bell's theorem asserts that if certain predictions of QM are correct then our world is non-local. Physicists refer to this ‘non-locality’ as meaning that there exist interactions between events that are too far apart in space and too close together in time for the events to be connected even by signals moving at the speed of light. Bell’s theorem has been in recent decades the subject of extensive analysis, discussion, and development by both physicists and philosophers of science. The relevant predictions of QM were first convincingly confirmed by the experiment of Alain Aspect (one our Nobel Prize winners) et al. in 1982, and they have been even more convincingly reconfirmed many times since. In light of these findings, the experiments thus establish that our world is non-local. I emphasise once again that this conclusion is very surprising, given that it violates the theories of relativity, as mentioned above.
In summary then, this year’s Nobel Prize for Physics has been awarded to Alain Aspect, John Clauser and Anton Zeilinger, whose collective works have used Bell’s theorem to establish to most people’s satisfaction (1) that Einstein’s conventional view of reality is ruled out (2) that quantum entanglement is real and (3) that quantum mechanics and quantum entanglement can be used to develop new technologies (such as quantum computing and quantum teleportation).
Usually, the Nobel Physics Prize is awarded to scientists whose work makes sense of Nature. This year’s laureates reveal that the Universe is even stranger than we thought, and in addition they achieved the rarest of things – they proved Einstein wrong!
John writes …
I am sure that many of our readers, on seeing the title of this post, will think of the use of DNA ‘fingerprinting’/ DNA profiling in police detection work. The discovery, by Alec Jeffreys and his team at Leicester University, that these profiles were unique to an individual enabled an identification of miscreants at a level of statistical certainty that had not previously been possible. Many of us remember the first conviction secured on the basis of DNA, that of Colin Pitchfork for the rape and murder of two teenage girls in Leicestershire (1). However, this was not the first time that the technique had been employed in the public arena. DNA fingerprinting had been used to establish that a young man from Nigeria was indeed the son of someone already living in the UK and could therefore stay here; the Home Office had disputed his claim and wanted to deport him. Both these examples show how the findings of science can be used in a way that promotes societal good.
One of the features of DNA profiling that often causes surprise is the small amount biological material needed in order obtain the profile. Obviously if a larger amount is available (such as from a blood sample), all well and good but if push comes to shove, the DNA from one cell is enough material to work with. This is nicely illustrated by a technique called Pre-implantation Genetic Diagnosis (PGD). As I have described elsewhere, prospective parents who are at risk of having a child with a genetic disorder may elect to undergo in vitro fertilisation (IVF) in order that the embryos may be tested for the presence or absence of the genetic mutation. In order to do this, just one cell is removed from the embryo at the eight-cell stage. This provides enough material for the genetic test.
One of the things we hear from time to time in relation to forensic use of DNA profiling is that a case has been re-opened because of ‘new DNA evidence’. Quite often this arises because forensic scientists are becoming better and better at extracting and purifying DNA from what appear to be unpromising biological samples. But these skills also have a role in other types of investigation, of which I will give three examples. The first concerns resistance to the plague-causing bacterium, Yersinia pestis. An international group of scientists have extracted DNA from the teeth of 206 human skeletons that were buried before, during and after the 14th century plague pandemic known as The Black Death (2). The level of detailed analysis that they were able to achieve with this material is truly remarkable. They were able to show that people with a mutation in a gene that regulates part of the immune system – a mutation that makes that part of the immune system more active – were 40% more likely to survive the plague than those without the mutation. Further, that mutation is still present in the population of modern Europe and people who possess it are more likely to suffer from an over-active immune system, leading to a variety of auto-immune diseases.
We think quite rightly that being able to analyse in detail the DNA from teeth that have been buried for 700 years is remarkable. However, the next two examples are even more amazing. A research team based at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany has extracted DNA from teeth and fragments of bone belonging to a group of eleven Neanderthals living in cave in Siberia 51,000 years ago. The team analysed DNA from the Y-chromosome, specific for males and mitochondrial genes which are passed down only via females. The analysis shows clearly the family and social structure of the little group as well as some insights into the life of this hunter-gatherer community. We do not have space to comment further on this but it is well worth reading a fuller commentary on this work, for example in New Scientist (3).
This brings us to our third example. One of the scientists who investigated the Siberian group of Neanderthals was Professor Svante Pääbo. Earlier this year he was awarded the Nobel Prize of Physiology and Medicine (4). He is an interesting choice because, unlike many Nobel Prize winners, he is not very well known in the wider science scene, despite his huge contributions to our understanding of the evolution of early humans and other hominins. This has involved refinement and improvement of methods for extraction of ancient DNA enabling Pääbo and his team to analyse and compare DNA from bones and teeth of Neanderthals, Denisovans (see Chapter 6 of the book) and early humans and DNA from a range of modern humans. This analysis included a full sequence of the nuclear genome of Neanderthals which was a truly remarkable achievement, almost worthy of a Nobel Prize on its own! His work showed that Neanderthals and Denisovans were ‘sister-groups’ existing for a time in parallel with humans (as we show on p. 148 of the book). He has also been able to measure gene-flow between these species resulting from limited inter-breeding and the extent to which present-day humans carry Neanderthal genes (and for Melanesian humans, Denisovan genes). Svante Pääbo is certainly an amazing DNA detective and a worthy winner of the Nobel Prize.
(1) I recently had the privilege of meeting one of the detectives (now retired) who had worked on the case.
(2) Evolution of immune genes is associated with the Black Death | Nature and Black Death 700 years ago affects your health now | BBC News.
(3) Neanderthal family life revealed by ancient DNA from Siberian cave | New Scientist.
(4) The Nobel Prize in Physiology or Medicine 2022 – Advanced information.
Graham writes ...
In case you were wondering what happened to the Artemis 1 mission …? Hurricane Ian put paid to the launch attempts and the SLS had to ‘run’ for cover back to the Vertical Assembly Building. The date of the next launch attempt is uncertain at the time of writing, but it is hoped that it may be in November 2022.
Graham writes ...
The DART spacecraft successfully impacted the asteroid Dimorphos in the early hours of this morning (UK time: 27 Sept), and I thought you might want to see what happened!
Please click here to see a video courtesy of BBC News showing the moments just before impact. We will learn in the coming days whether the experiment was successful in changing Dimorphos's orbital speed, and consequently its orbit around Didymos.
Graham writes …
Alongside the impact event of the DART mission (see next blog post below), the other big happening this month is the proposed launch of the Artemis 1 mission – the first uncrewed test of the systems that are intended to return astronauts to the moon.
The objectives of the Artemis programme are to establish a permanent crewed base on the moon, and to enable and test the necessary systems required for future missions beyond the moon. After the lack of ethnic diversity of the Apollo moon-walking astronauts, another unofficial aim is to take women and Black astronauts (and indeed Black women astronauts) to the lunar surface. NASA have already identified its ‘Artemis Team’ of 18 American candidates, and the involvement of other space agencies – ESA (European Space Agency), JAXA (Japan Aerospace Exploration Agency) and the CSA (Canadian Space Agency) – ensures a mix of other nationalities in future landing crews. The Artemis programme will also be supported by other initiatives, in particular the Lunar Gateway, which is a small, lunar-orbiting space station. This is expected to be in place by about 2027, and is intended to operate as a solar-powered communications node, a science laboratory and a short-term habitation module for astronauts.
Unfortunately, the efforts to launch the Artemis 1 mission have not been successful so far. The first attempt took place on 29 August, but was abandoned because the temperature of one of the four main engines was indicated to be above the maximum allowable for launch. A second attempt, too, was aborted on 3 September due to a service arm fuel supply line leak. I have to admit that I tuned in on both occasions to NASA’s excellent live stream HD TV coverage with great excitement and anticipation. At my ‘great age’, I feel very impatient to see space exploration programmes up and running again – I just want them to get on with it! The next launch opportunity is 27 September, with a back-up on 2 October, and I shall be tuning again to the live coverage.
The Artemis 1 mission will be the first outing of the Orion spacecraft, which is planned to be of 38 days duration. Looking at the spacecraft configuration, at first sight it looks very much like the Apollo Command and Service modules, with the obvious difference being that Orion has deployable solar arrays for power generation. The power system on Apollo used fuel cells, which are effectively chemical engines that need an input of hydrogen and oxygen to produce electricity and water. This change facilitates the need for an additional water tank to supply the crew’s needs. However, the most significant difference is that the cone-shaped Orion crew module is significantly larger than the equivalent Apollo module, with about 30% more interior volume. Consequently, Orion missions will accommodate four crew members for a typical mission duration of about 21 days.
Another significant difference is that the Orion Service module is European in design and manufacture. This cylindrically-shaped module is based upon ESA’s Automated Transfer Vehicle (ATV) (1) and provides the necessary services, such as power, propulsion, communications and life support & environmental control, required to keep the crew alive and to ensure a successful mission. The Orion system’s main engine, located at the rear end of the Service module, is a souped-up version of the Space Shuttle’s orbital maneuvering system engine, with a thrust of 33 kN. Mention of this prompts memory of a very unlikely encounter a while ago with a NASA engineer who worked on the development of this Shuttle propulsion technology for the Orion spacecraft. In 2011, my wife and I had a lovely holiday break walking the coastal path of Pembrokeshire, South Wales, and on this particular day I was wearing my NASA baseball cap. Coming the other way was a couple, and the gentleman was wearing a similar cap. We started to converse, and found that we shared a professional interest in space technology. He told me about his work on the Orion programme, and I told him about the upcoming, and ground-breaking ESA comet lander mission, called Rosetta, which he’d known nothing about. A remarkable meeting, in a beautiful place in lovely weather, which would not have happened if I hadn’t been wearing my NASA cap to protect me from the sun!
Anyway, back to Artemis. One thing that surprised me about the new Space Launch System (SLS) was that NASA has returned to the Saturn V philosophy used on the Apollo programme launches. This is along the lines of stacking everything– the crew and service modules, plus the lunar lander module – all on one rocket. The reason for my surprised reaction is the intention to put people on top of such a large vehicle. The energy contained within its chemical propellants is equivalent to that of a small atom bomb. Despite the existence of a dedicated launch escape system, this seems to me to be an unnecessary risk. The Agency got away with it on the 13 Saturn V launches during the Apollo era, but why take the risk now?
There is in fact a better – safer and more flexible – way of doing this, which was proposed during the Constellation ‘return to the moon’ programme in around 2004. At that time, the imminent retirement of the Space Shuttle in 2011 dictated a rethink of the American space programme by the then-Bush administration. There had been a realization – a hard lesson learned – that complex spacecraft like the space shuttle are dangerous. Seven flight crew were killed on launch in the Challenger accident in 1986, and another seven died when the shuttle Columbia broke up on reentry in 2003. In light of this, a new approach to launching people was recommended in the Constellation programme. In this proposal, to launch the crewed Orion spacecraft a new man-rated launch vehicle was developed called Ares 1 using existing components derived from Shuttle and Apollo hardware. This new vehicle was small and very simple, with a genuine crew escape system, with the result that it would be very reliable and safer for future crew launches to Earth orbit and for lunar missions. The hardware for the mission, for example the lunar lander, equipment required for developing or supplying a moon base and a propulsion stage, would be launched separately on an uncrewed, heavy-lift launch vehicle, called Ares 5. Subsequently, the crewed vehicle and the mission payload vehicle would rendezvous in orbit, before departure for the moon.
Although the Ares 1 and 5 launch vehicles were to be developed primarily for lunar missions, NASA envisaged a wider role for them involving crewed space missions to destinations other than the moon. A test flight of Ares 1 was performed, designated Ares 1-X, but nevertheless the Constellation programme was cancelled by the incoming Obama administration in 2010. With the retirement of the Shuttle in 2011, this left the US Space programme in the remarkable position of being principal operator of the International Space Station, but without any means for US astronauts to reach it in Earth orbit, other than by ‘hitching a ride’ on Russian crewed vehicles. For more detail about the Constellation programme, please see (2).
You might ask, why am I discussing return-to-the-moon space programmes in a blog to do with science and faith? Well firstly, with my physicist’s hat on, the Artemis launch is a truly major event in the realm of the physical sciences. But then secondly, and perhaps less obviously, the spiritual or religious experiences of astronauts are worth reflecting upon. And this is not limited to moon-walking astronauts, but can be extended to those who have spent considerable time in Earth-orbiting space stations.
It is no secret that several of the Apollo astronauts were practicing Christians. Perhaps the most overt evidence of this is the remarkable occasion when the three astronauts aboard the Apollo 8 lunar-orbiting mission, Frank Borman, Jim Lovell and William Anders, read the first 10 verses of the first chapter of Genesis on Christmas Eve in 1968 (3). Then, on the occasion of the first historic landing mission Apollo 11, shortly before the lunar surface walk lunar module pilot Buzz Aldrin addressed the people of Earth: “I would like to request a few moments of silence … and to invite each person listening in, wherever and whomever they may be, to pause for a moment and contemplate the events of the past few hours, and to give thanks in his or her own way”. He then celebrated communion (the taking of bread and wine in remembrance of the sacrifice of Jesus Christ). Also, the commander of the final landing mission Apollo 17, Eugene Cernan, made no bones about his faith and was awed by what he believed was God’s amazing creation while on the lunar surface. He later commented: “There is too much purpose, too much logic [in what we see about us]. It was too beautiful to happen by accident. There has to be somebody bigger than you, and bigger than me …” (4). Other moon-walking astronauts related spiritual experiences induced by their journey to the lunar surface. Notably Apollo 14 astronaut Edgar Mitchell commented that “something happens to you out there”, and Apollo 15 astronaut Jim Irwin quoted the Bible during his lunar walk (5), and felt “touched by grace”.
I guess it’s not too surprising that devout spacefarers would relate how their lunar mission influenced and strengthened their faith. Perhaps what is more remarkable is that many experienced a spiritual dimension in their lunar visit, simply by virtue of the ‘cosmic awe’ they encountered. It would seem that space in some way connects us to the divine.
(1) The ATV was used for supply missions to the International Space Station up to 2015.
(2) Graham Swinerd, How Spacecraft Fly: Spaceflight without Formulae, Springer, 2008, pp. 222-225.
(3) Graham Swinerd & John Bryant, From the Big Bang to Biology: where is God? KDP publishing, 2020, p. 45.
(4) Ibid., p 208.
(5) Holy Bible (NIV) Psalm 121:1 “I lift my eyes to the mountains – where does my help come from?”
Graham writes …
This blog post is a very brief heads-up about the upcoming impact event, which is the centre piece of NASA’s DART (Double Asteroid Redirection Test) mission. This will occur, as planned, on 26 September. For more detail about the mission, please refer to the December 2021 blog post, which includes a video discussion between John and myself.
Essentially, this is the first spacecraft mission devoted to planetary defense science. In particular, the objective is to study the effectiveness of the kinetic impactor technique in changing the orbit of an asteroid to prevent a future, devastating asteroid collision with our home planet. Although such collisions with a large asteroid (greater than, say, 1 kilometre in diameter) are very rare, nevertheless we know that such events are inevitable in the long term. For this test, the target asteroid is a 160 metre diameter object called Dimorphos, which itself is in orbit around a larger asteroid (780 metres across) called Didymos. It’s worth pointing out that neither object poses an impact threat to the Earth! The idea is that the spacecraft will impact Dimorphos, causing a tiny change in its orbital speed. Although this change is very difficult to measure directly, the magnitude of the change can be calibrated very precisely by observing long-term changes in Dimorphos’s orbit around Didymos. In particular, the resulting cumulative change in its orbit period over many orbit revolutions can be observed subsequently using Earth-based telescopes.
Watch out for media coverage of this historic event in the coming days, and for information about what DART tells us about planetary defense in slower time.
John writes ...
In June’s post on this blog, I wrote about the CO2 emissions arising from production of different types of food; I also looked at the amount of land needed to produce the same range of foods. The obvious conclusion to draw from these data is that, both nationally and globally, we need to reduce the consumption of meat and meat-based foods in favour of plant-based foods. A similar conclusion was made in the 2020 report published by the UK Government’s Food Adviser, Henry Dimbleby (1). I need to emphasise that neither Dimbleby nor I are saying that everyone must be vegetarian or vegan; that is a matter of personal choice (we also note that some types of land are not suitable for crop production). However, we are emphasising that for the sake of the climate (and biodiversity) and in order to feed a growing global population, total meat consumption needs to be drastically reduced and plant-based food consumption needs to be increased. From a Christian perspective we can say that this shift is an aspect of both good stewardship and care for our neighbour.
This imperative to increase the consumption of plant-based foods also has implications for the plant science research community. Can we improve productivity, increase the efficiency of land use while at the same time reducing the need for application of fertilisers and pesticides? Understanding how plant genes work at the most fundamental level was the main area of my own research for many years. The combination of this level of research with studies of plant growth and crop yield will be vital if plant-based agriculture is to meet the challenges of the 21st century and beyond, as I recently discussed with my friend and colleague, Professor Ros Gleadow.
In addition to being a Professor at Monash University, Melbourne, Ros is President of the Global Plant Council, an organisation dedicated to promotion of plant science education and research and to social and global justice in the applications of developments in the science. Earlier this summer she came to Europe to attend some conferences and meet other plant scientists. She spent two days in Exeter during which we were able to have extensive discussions about plant science research in general and our own interests in particular.
During her visit we spent a few hours in the Department of Biosciences at Exeter University, talking to some of the plant molecular biologists about their research. Amongst the several beautiful (and I use the word deliberately) projects, I want to mention just two. Firstly, many years of focussed research have revealed a network of responses at genetic level to the main stresses that climate change impose on plants, namely heat and drought. This will facilitate the breeding of crops (probably using GM and genome editing techniques) that are more resilient to climate change. Secondly, plants that apparently cope well with increased temperatures may be less able to cope with other stresses such as attacks by bacteria, fungi or viruses. It is a complex picture that will need more work to understand.
More recently I have been able to continue my conversation with Ros, now back in Melbourne, courtesy of Zoom.
There is a video that accompanies this blog post, which you can see by clicking here.
We talk about the work of the Global Plant Council, about the need for fairness and equality in all aspects of plant science and its applications and about priorities in plant science research. One very recent development that excites both of us is the use of GM technology to increase the efficiency of the mechanisms that plants (in this case, soya bean plants) use to capture the energy from sunlight. This led to a very marked increase in the rate of photosynthesis. It may be hard for non-biologists to appreciate how amazing this is. Because photosynthesis traps and uses energy from the sun, it is the ‘engine’ that drives all life on Earth. For an individual plant, increased rates of photosynthesis imply greater growth rates and greater productivity which is exactly what the international team of researchers found. The importance of this work was recognised by the media. In the UK, ‘serious’ newspapers (2) ran articles on it and it also featured on the BBC’s website (3). The excitement is certainly justified. If the technology can be used with other crops and especially with the major cereals, it will be a real ‘game-changer’ for global food production. As the research team leader, Professor Stephen Long, University of Illinois stated ‘This result is really relevant right now, [when] one out of 10 people on the planet are starving’. So, watch this space: we will report significant developments here.
(1) In a recent interview by The Guardian newspaper, Dimbleby repeated this recommendation: ‘England must reduce meat intake to avoid climate breakdown, says food tsar’, The Guardian, 16 August 2022.
(2) E.g., ‘New GM soya beans give 25% greater yield in global food security boost’, The Guardian, 18 August 2022.
Graham writes …
After decades of development, and 6 months of launch, deployment, orbit acquisition and commissioning, the JWST is finally ready for action. It was on the 12th of July 2022 that NASA/ESA/CSA (1) released the first science results of the new space observatory, and these received significant media attention. In what follows, I will give a brief overview of the science revealed in the new images. For direct access to these and future images, and their interpretation, you can find the JWST image gallery by clicking here.
One of the most striking is the first JWST deep field image, as shown below. To acquire this, the telescope is pointed at a fixed position on the celestial sphere for an extended period. The Hubble Space Telescope (HST) acquired similar deep field images, but these took multiple weeks of stable pointing to build the images. This first JWST deep field was achieved in less than a day, and this is mainly because of two factors – the light gathering area of the JWST mirror is nearly 8 times more than that of the HST, and the JWST is optimized to operate in the infra-red (IR) part of the spectrum.
In previous blogs I have discussed what the IR optimization means, but it’s worth a brief recap. As you may recall, the IR part of the spectrum corresponds to heat radiation, as you can experience when sitting by a well-stoked open fire. It may appear strange to design the telescope to operate in this part of the electromagnetic (EM) spectrum, until one realises that we ‘see’ very distant objects – such as the first stars and galaxies – in this part of the spectrum. When these ancient objects formed, they generally emitted the peak of their radiation in the visible part of the EM spectrum. However, due to the expansion of the Universe, the fabric of space-time itself has significantly ‘stretched’, and by the same token so has wavelength of the emitted radiation. So all those interesting events that occurred just a few hundreds of millions of years after the creation event are most readily studied now by examining the IR part of the EM spectrum, which is at longer wavelength beyond visible red . See (2) for more detail.
The other advantage of using IR, as you may recall, is that the longer wavelength is scattered less by dust and debris, as illustrated by the accompanying images both acquired by the HST. The comparison shows the Carina Nebula in visible light (left) and infrared (right). The visible band image may be more pleasing aesthetically, but the infrared image is more revealing scientifically and, in this case, exhibits stars that weren’t visible before.
Getting back to the JWST deep field image, remarkably the angular size of the image on the sky is equivalent to the angle subtended by a grain of sand at arm’s length! So, all the stars (local to the Milky Way galaxy), galaxies and other features are all contained within a very small area of the sky. One can only try to imagine how many galaxies there may be across the entire sky. HST deep field images suggested a total of about 100 billion galaxies in the visible Universe, but it will be interesting to see what an updated JWST estimate may be. The other obvious features are the apparently distorted images of galaxies, that appear as stretched curved arcs of light. These are due to a phenomenon known as Einstein Rings, although in this case the rings are obviously fragmented. These are created when light from a galaxy or a star passes by a massive object on its way to the Earth. The massive object produces a gravitational lens which bends the light. If the source, lens, and observer are all in perfect alignment, the light appears as a ring, hence the name.
Clearly there are galaxies galore in this single image, many of which are billions of light years distant. One of the principal aims of the JWST project is examine the processes that led to the development and evolution of galaxies. To demonstrate the power of the JWST NIRSpec (Near Infra-Red Spectrometer) instrument, the science team identified a galaxy, the light from which has taken 13.1 billion years to reach us (recall that the Big Bang event is occurred around 13.8 billion years ago). Examining this light, the team produced the spectrum below, which features several prominent emission lines corresponding to its chemical composition. Please refer to the May 2022 blog post for more details of the JWST payload instruments.
Coming closer to home, the new observatory is also able to analyse the atmospheres of exoplanets – planets outside our own Solar System – using the NIRISS instrument (Near Infra-Red Imager and Slitless Spectrometer) to attempt to detect potential signatures of life elsewhere. The target test planet is about 1,150 light-years away located in the southern-sky constellation of the Phoenix. Designated ‘WASP-96 b’, it is a large, hot planet orbiting very close to a Sun-like star (and therefore not in the circumstellar habitable zone). As can be seen in the image below, the JWST spotted the unmistakable signature of water, signs of haze and evidence of clouds. Please note that the background image of a planet is there for purposes of presentation, and is not an image of WASP-96 b. But one thing that can be said, however, is that this is the most detailed exoplanet spectrum yet acquired.
Remaining within the Milky Way galaxy, at about 8,000 light years distance and in the Southern constellation of Carina (the keel), lies the Carina Nebula (NGC 3324). This remarkable object is a huge cloud of gas and dust which is effectively a stellar nursery. One of the first JWST images shows a small part of this nebula – see below. While taking a moment to appreciate the beauty and scale of the scene, it is also the case that it offers the science community the opportunity to examine the relatively ‘rapid process’ of stellar birth, which typically lasts only a few tens of thousands of years. In this image, previously hidden baby stars have been uncovered by JWST’s infra-red eye. In this type of object, the new telescope is able to reveal a significant number of such embryonic stars at different stages of their development, so allowing better understanding of the evolutionary process of stellar birth.
The next image is, again, of a ‘local’ object, the Southern Ring planetary nebula (NGC 3132) which is about 2,000 light years away in the southern sky constellation of Vela (the sails). The first thing to note is that planetary nebulae have nothing to do with planets. They are stars that have cast off a glowing ring of gas, which produces a roughly circular object. In the old days this disc-like object could be confused with the image of a planet. The JWST image below shows two views, using different payload instruments. The picture on the left was acquired using the NIRCam (Near Infra-Red Camera) instrument. In this part of the EM spectrum the image is closer to that which would be acquired in the visible band, showing off the surrounding stars and detail of the ejected gas and dust cloud. The image on the right was acquired using the MIRI (Mid Infra-Red Instrument), and at these longer wavelengths the telescope can penetrate some of the obscuring gas and dust to reveal that the central object is actually a binary star. The two stars orbiting around each other are very close, one being blue and the other red. It is likely that it was the red star that shed the gaseous layers to produce the overall disc-like image.
Finally, we go extra-galactic again in the last image of this initial release of JWST pictures - see below. This shows a feature called Stephan’s Quintet (NGC7318B - the brightest member), named after the astronomer who discovered it in 1877. This comprises five galaxies, four of which are gravitationally bound together. The galaxy on the left-hand side of the picture is actually much closer to us than the rest of the cluster. The four local members are about 290 million light years distant, in the northern sky constellation of Pegasus (the winged horse). The picture is a composite, built from about 1,000 JWST images in both the near and mid infra-red parts of the spectrum. The angular size of the image is about 1/5 the diameter of the moon (approximately 6 arc minutes) and also features foreground stars (local our own Milky Way galaxy) distinguished by the 8-spiked diffraction pattern. Remarkably, all the other objects in the image are very distant galaxies. I haven’t tried to count them but they must number in the hundreds.
I hope you have enjoyed this brief tour through the first JWST science images. It has certainly been worth waiting out the many years needed to bring the JWST project to fruition. Speaking as a scientist, I think they are awesome, and no doubt herald the beginning of yet another historic chapter in the annals of astrophysics and cosmology. There is a whole lot more to come in this story! As a Christian believer, the images bring into sharp focus the words of Psalm 19, verse 1: ‘The heavens declare the glory of God; the skies proclaim the works of his hands’(3). In my Christian journey, my first step, inspired by the science, was that I had become more comfortable with the idea of a creator God as the engineer of the observed fine-tuning of the cosmos (see (4) for more detail). By the same token, each time I experience the brilliance and warmth of the Sun on a beautiful summer’s day, that ‘gravitationally-bound fusion reactor’ in the sky brings home the notion of God’s creativity and power. In the same way, these new data from the JWST are an amazing reminder of God’s power and majesty. Wow!
John writes …
Plants and our planet.
My PhD supervisor, Dr (later Professor) Tom ap Rees often quoted the phrase which I have used as the title of this blog. It is actually part of a verse from the Bible: 1 Peter, chapter 1, v 24: All flesh is grass and all its glory like the flowers of the field; the grass withers and the flowers fall … . The verse refers to the transience of human life and my supervisor had doubtless heard his father, a church minister, quote it at various times. However, Tom ap Rees’s use of it in our lab conversations took us in a very different direction. He was referring to our total dependence on plants, which was one of his major motivations for doing research on how plant cells control their metabolism and which has driven my research on plant genes and DNA.
Let us look at this a little more closely. I am very fond of saying that without plants, we would not be here. This may seem rather sensationalist but it is true. It is a statement of the dependence of all animals (and indeed of many other types of organism) on green plants for their very existence. We see hints of a partial understanding of this in the media as they debate ways of mitigating climate change. Planting trees is correctly lauded as a means of capturing carbon dioxide from the atmosphere while at the same time releasing oxygen. Further, these two features have featured strongly in the evolution of life on Earth, as we describe in Chapter 5 of the book: the first occurrence of photosynthesis in simple micro-organisms (similar to modern blue-green bacteria) about 2.8 billion years ago and the invasion of dry land by green plants about 472 million years ago had major effects which have led to the development of the biosphere as we know it today.
However, what is often not emphasised enough in our discussions is that the process which takes in carbon dioxide and gives out oxygen, namely photosynthesis, uses energy from sunlight to drive the synthesis of simple sugars. This process requires light-absorbing pigments, mainly the chlorophylls which are green because they absorb light in the red and blue regions of the spectrum. The mixture of light wavelengths which are not absorbed gives us green. Green plants are thus our planet’s primary producers. This ability of plants to ‘feed themselves’ (autotrophy) is essential for the life of all non-autotrophic organisms, namely animals of all kinds, fungi and some micro-organisms. Non-autotrophic organisms such as ourselves are thus directly or indirectly dependent on green plants for their nutrition. We eat plants or we eat organisms that themselves eat plants. Thus, I repeat ‘Without green plants we would not be here’. ‘All flesh is grass’.
Plants and population.
I now want to look at this in the context of feeding a hungry world at a time of changing climate (1). Current estimates from charities such as TEAR Fund, Christian Aid and OXFAM indicate that about 800 million people are undernourished. In 2020, 9 million people actually died from malnutrition. This compares to the total number of deaths from malaria, HIV, TB and flu combined, of 3.17 million in the same year. Poverty is undoubtedly one of the main drivers of this situation: food needs to be more readily and cheaply available but food production also needs to be increased. Further, current projections suggest that the global population will increase to about 9 billion by 2050, an increase of about 1.05 billion on the current figure (2), with the vast majority of the increase occurring in low and middle-income countries (LMICs). At the same time, agricultural land is being lost to the effects of climate change and there is also some loss in order to house the increasing population. The situation has been described as a perfect storm.
I am going to focus specifically on the tension between two imperatives that I described in the previous paragraph, namely care for planet Earth and care for its human inhabitants. What are the environmental ‘costs’ we incur as we produce enough food for a population which is already fast approaching 8 billion and which is set to reach 9 billion within 30 years? The table below sets out one of those costs, namely the production of greenhouse gases. It is immediately and obviously apparent that farming of animals for food is far more ‘expensive’ than farming of crops. For example, beef production produces more than 50 times the quantity of greenhouse gases per kilogram of food than does wheat production. We need to note in passing that this way of expressing the data (‘per kilogram of food product’) places milk (whether from cows, sheep or goats) in an anomalously low position on the chart because 1 kg of milk is largely water. We get a better idea of the costs of producing the main nutrients in milk – protein and lipid - by looking at cheese production.
I now want to look at two other aspects of the costs of food production, land use and water use. These must both come into our consideration as we attempt to balance the tensions involved in ‘feeding the nine billion’. Firstly, about 75% of the world’s agricultural land is used for animal production. This figure includes land that is used to grow crops for animal feed. Crops for direct human consumption occupy the remaining 25%. However, the yield of food obtained from just one quarter of the total agricultural land exceeds that obtained from the three quarters devoted to farming animals. Indeed, depending on the particular animal under consideration, the average protein yield per hectare of crop land is six times that of land devoted to animal husbandry.
Secondly, there is water usage which, like land use, shows a huge difference between plant- and animal-based food production, as is shown in the following table, taken from Mekonnen and Hoekstra (2010).
Overall then, the data from agricultural science and biogeography indicate that crop growth is ‘better’ for the planet than animal farming and that concentrating more on crops than on animals is likely to be the better route to feeding the burgeoning population. However, I am not forgetting that some land is better suited to animals than to crops, as discussed by Isabella Tree in her book Wilding (3). Nor am I trying to dictate that we should all move to a plant-based diet: in the rich industrialised nations of the world, we are privileged that this is a matter of personal choice. Nevertheless, it is clear that there must be extensive focus on plant science - genetics, molecular biology, biochemistry and physiology - over the next 20 years, both in respect of mitigating climate change and in respect of global food production. That science will be the subject of a future blog.
John Bryant and Graham Swinerd comment on biology, physics and faith.