Historians have named several periods of the past by the material that typified the industry of the time, whether it be the Stone Age or Bronze Age or Iron Age. In keeping with that methodology our present period of history should then be called the Silicon Age. Computers and other electronic devices are everywhere nowadays, you carry your smartphone with you where ever you go but there are dozens of other electronic devices in your home as well. Your oven, washing machine, refrigerator even your car all have integrated circuits in them while of course your TV and computer are virtually nothing but Integrated Circuits made of silicon.
Out world today is built not of stone or steel but of electronics, and that means silicon. (Credit: Electrical Technology)
All of that is due to silicon’s properties as a ‘semi-conductor’ that is silicon is a material that doesn’t conduct electricity as well as a conducting metal, say copper or iron do, but it does conduct electricity better than an insulator like rubber or wood do. With all of the silicon electronics now being manufactured it’s rather surprising therefore to learn that silicon isn’t really all that good of a semi-conductor.
Silicon in its pure state. Silicon is one of the most abundant elements on Earth so its use in electronics is based more on its being a cheap semi-conductor rather than a good semi-conductor. (Credit: Wikipedia)
Silicon’s biggest problem is that while it does conduct electricity fairly well it is very bad at conducting heat away from the electronics. That’s why so many of our electronic devices get so hot, and require extra cooling systems to remove that heat before it reduces both the performance and lifespan of those electronics. Even as a semi-conductor however silicon is simply not as good as its rivals germanium (Ge) or gallium-arsenide (GaAs).
The first transistor, built back in 1947, used Germanium as its semi-conductor because Germanium is just a better semi-conductor. (Credit: Computer History Museum)
The primary factor of how good a semi-conductor material performs is called its carrier mobility, which is measured in units of centimeter-squared per volt second. There are actually two kinds of mobility, one for the electrons themselves called electron mobility and the other is ‘hole’ mobility, the mobility of places where an electron should be but isn’t. In a semiconductor a hole will actually behave like a positively charged electron. While the electron mobility of silicon is fairly good at 1400cm2/V*s, its hole mobility is much lower, only 450 cm2/V*s.
Carrier mobility is the basic property that makes a semi-conductor useful in electronics. Like all semi-conductor materials the carrier mobility in silicon is heavily dependent on temperature. (Credit: Quora)
So why do we use silicon then? As you might guess cost is the major factor, germanium and gallium-arsenide are both considerably more expensive and gallium-arsenide is very toxic to boot, adding further to the cost of using it. Because of these drawbacks materials scientists are always on the lookout for new semi-conductor materials in the hope of finding a replacement for silicon.
Despite being more expensive and dangerous to make Gallium Arsenide continues to be used as in electronics and solar cells simply because it is a much better semi-conductor material. (Credit: Phys.org)
Now researchers at the University of Houston have identified a new semi-conductor material that not only surpasses silicon in performance but may actually approach the theoretical limit to semi-conductor performance. The material is called Cubic Boron-Arsenide (c-BAs for short) and is a crystal grown from the two elements Boron and Arsenic. To date only tiny crystals of c-BAs have been manufactured, and those have contained impurities, but recent measurements of c-BAs have shown that it possesses ten times the thermal conductivity of silicon while at the same time having a carrier mobility in excess of 1600 cm2/Vs for both electrons and holes. Based on their measurements the researchers also think that, if the impurities were removed, carrier mobility could reach as high as 3000 cm2/Vs.
Cubic Boron Arsenide is the newest semi-conductor material being studied right now. So far its properties are better than any other known material. The question is of course cost! (Credit: American Physical Society)
Of course right now c-BAs is even more expensive than Ge or GaAs but to date very little research has been carried out to see if it can be manufactured on an industrial scale. If it can then c-BAs may become the new silicon, pushing the performance of electronics still further while improving their reliability and life span.
The like expectancy of electronics, known as the Mean Time To Failure or MTTF is heavily dependent on temperature. If c-BAs can improve the life span of our electronics that may help offset its greater cost. (Credit: JetCool)
Ok, so what is it about these semiconductors that make them so valuable in electronics. To answer that question we first have to discuss the process of doping of a semiconductor. As I said above, semi-conductors will allow both electrons and electron holes to move through them, but not very well. If a very small amount of another element is mixed in however, about one atom of the other element for every 100 million atoms of silicon, that mobility can be greatly increased. For example adding that tiny amount of phosphorus to silicon increases its conductivity by a factor of 10,000.
Even a small amount of doping can greatly change of the conductivity of a semi-conductor. The ability to so easily control the electrical properties is what makes semi-conductors so useful. (Credit: Halbleiter.org)
This process is called doping and whether the increase is for electrons or holes depends on what material the silicon is doped with. Doping with phosphorus or antimony for example creates N-type silicon increasing the electron mobility. Doping with Boron or indium on the other hand results in P-type silicon with increased hole mobility. When a slice of N-type silicon is placed against a slice of P-type a semiconductor junction is formed where the free electrons can move into the holes but the holes cannot move into the electrons. In such a N-P junction electric current can only flow in one direction, a device known as a diode. Two such junctions, whether NPN or PNP form a transistor that can be switched ON or OFF or used to amplify a signal.
PNP and NPN transistors act as tiny switches, turning ON and OFF millions of times a second. That simple function has made them the most important devices in the world today. (Credit: Electronics Hub)
Semiconductor junctions can also both convert electric current to light, a Light Emitting Diode or LED, or convert light to electric current as in a solar cell. They can also convert heat to electricity or electricity to heat, that last part is easy. With all of its many applications it’s no wonder that materials scientists will continue to search for better, and cheaper semi-conductors.
With all of the mass shootings taking place across the United States nowadays it seems that we’ve all just come to accept the massive amounts of bloodshed as ‘normal human behavior’ against which nothing can be done. In keeping with this philosophy the National Rifle Association (NRA) along with their Republican lawmakers continue to assert the premise that ‘The only thing that can stop a Bad man with a Gun is a Good Man with a Gun.’
The idea of ‘Justice’ being provided by a ‘Good man with a Gun’ is old and maybe someday we’ll recognize that it’s also obsolete. (Credit: Buffalo Bill Center of the West)
But a premise is not an observed fact, and to be considered true a it must stand the test of comparison against actual observations. That means that the premise about good men stopping bad has to be judged by those shooting incidents where the bad man with a gun was stopped by one or more good men with guns. I would like to do just that using the recent mass shootings at Robb elementary school in Uvalde Texas and the Greenwood Park Mall in Greenwood, Indiana. I will argue that these two events represent the two extremes in the reactions of the ‘good man’ to the problem of the ‘bad man’. As such they are what a physicist would call boundary conditions which can be used to give insight into all of the possible outcomes of the ‘good man / bad man’ premise.
It’s become an unending dirge of mass shooting after mass shooting in this country. This is just a typical weekend in America today. (Credit: ABC News)
In both of these incidents the shooter acted without any immediate provocation or intent to achieve some rational goal. Instead the perpetrators simply carried an arsenal of weapons to a place where a large number of innocent people would be and begin firing with the aim of killing as many people as possible. In neither incident did the assassin have a prior record of violence sufficient enough to prevent them from purchasing their weapons legally, nor for each killer has a motive has been discovered for their heinous acts. For these reasons the shooter in both the Uvalde, Texas and the Greenwood, Indiana mass shootings certainly can be classified as a ‘Bad Man with a Gun’.
The victims of the shooting at Robb Elementary School in Uvalde Texas. While they died over a hundred ‘Good Men with Guns’ stood around doing nothing. (Credit: WSVN)
Also, in both Uvalde and Greenwood the bad man with a gun was demonstrably stopped, killed actually by a good man with a gun. In Uvalde the shooter, whom I will not name, was killed when local police stormed the schoolroom where he had barricaded himself. In the Greenwood shooting it was an ordinary citizen, just someone who was himself licensed to carry a firearm, who engaged and killed the mass shooter. The main difference between the two confrontations is in the competence of, and most importantly the speed with which the good man reacted to the life and death situation at hand.
If the Good Men with Guns just stand around and do nothing they certainly aren’t going to stop any Bad Men. (Credit: Complex)
At Uvalde a laundry list of ‘systemic failures’ along with an unwillingness to act by senior law enforcement officers led to a 77 minute delay, after the shooter had begun his rampage, before the assassin was finally confronted and subdued. During all that time 19 children and two of their teachers lay dead or dying while others who still lived were at the mercy of the shooter. Certainly part of the reason for the delay was the large number of different law enforcement agencies that responded to the active shooter alert. Of the 376 good guys who showed up at Robb Elementary 149 were members of the U.S. Border Patrol while 91 were state police, the vaulted Texas Rangers. It seems as though these state and federal officers thought that local police should take charge because of their superior knowledge of Robb Elementary and the people there.
Managing Chaos requires a particular skill set that obviously nobody at Robb Elementary School possessed. (Credit: Dreamstime.com)
And there were more than enough local police at the scene. 12 Arredondo’s Sheriff’s Deputies along with 25 members of Uvalde’s police force of whom 5 were school police. All in all there were simply too many cops from too many agencies with no one willing to step up and take charge. Confusion as to room keys and whether any of the kids in the room could still be alive added to the chaos but in any case Robb Elementary School in Texas is an excellent example of just how badly a ‘good man with a gun’ can handle a ‘bad man with a gun’. In other words, it is undeniable that in some cases good men cannot be relied upon, some better solution must exist and must be found.
The ‘Keystone Cops’ were a metaphor for bureaucratic incompetence that still works today. (Credit: Gfycat)
The shooting at Greenwood Mall in Greenwood, Indiana is just the opposite. When a shooter opened fire at the Mall’s Food Court with his assault rifle local citizen Elisjsha Dicken was having lunch with his girlfriend. As he heard the gunshots Elisjsha, who is legally permitted to carry a firearm in the state of Indiana, immediately took out his own pistol and calmly fired ten rounds, mortally wounding the shooter. Unfortunately, despite Dicken’s heroic actions the killer still managed to kill three innocent people and wound a fourth before being taken him down.
Greenwood Park Mall in Indiana is no different from a thousand malls across America and unfortunately as the site of a mass shooting it’s become typical of part of our culture as well. (Credit: WNDU)
At Greenwood the good man reacted immediately, stopping the assassin before he could harm anyone else, therefore it can be argued that Elisjsha Dicken represents the best case scenario of the ‘Good Man with a Gun stopping a Bad Man with a Gun’. Three innocent people still got killed however, the best case scenario was still a mass shooting with multiple dead and wounded.
Elisjsha Dicken was the “Good Man’ who reacted quickly and stopped the ‘Bad Man’. Still three innocent people died despite Elisjsha’s best effort. (Credit: CNN)
I have argued above that Uvalde and Greenwood can be considered as approximating the worst and best case of the possible outcomes for the ‘The only thing that can stop a Bad man with a Gun is a Good Man with a Gun’ premise. If that is so it is clear that even the best case scenario is still horrific and every other possibility progressively worse making the premise demonstrably false.
Relying on Good Men with Guns to stop the Bad Men may seem romantic but it still means we have to live in a violent, horrible world. Are we really going to admit that we aren’t intelligent enough to find a better solution. (Credit: Facebook)
Therefore, if we do in fact want to try to reduce the level of gun violence in this country, and yes it is true we cannot even hope to completely stop it, then we must find a new premise to test. Of course everyone already knows what that premise is, ‘The best way to stop a Bad man with a Gun is to NOT LET THEM GET A GUN in the first place’.
So long as guns are a big part of American Culture is it only a matter of time before someone points a gun at you!!!!! (Credit: Southern Arizona Attractions Alliance)
In other words gun control, eliminating military style weapons completely along with high capacity magazines. At the same time we must adopt stricter background checks to keep people with mental problems from acquiring firearms. None of these suggestions have to adversely effect legitimate hunters or those who want to purchase a gun to protect their homes. They will however reduce the current high frequency of murders in this country, not just the mass shootings. Gun violence in the US has grown tremendously over the last thirty years, it’s time to finally do what we all know is the only thing that will actually work.
Over the last century astronomers have discovered a veritable zoo of strange objects inhabiting the Universe. Starting with other galaxies beyond our Milky Way they have also studied and named things like Pulsars and Quasars, Active Galactic Nuclei (AGN) and Black holes (see my posts of 17 April 2019 and 26 March 2022) and two distinct types of Supernova (see my posts of 26 May 2021 and 18 January 2020). Like any wildlife expert when astronomers find a new beast out there they first have to compare the object to a checklist of the things they already know before they even consider a new announcing a new species of astronomical animal. A case in point is the recent detection of a new radio source coming from a galaxy known as NGC 2082, a G type spiral about 60 million light years from the Milky Way with a diameter of an estimated 30,000 light years that lies in the constellation of Dorado in the southern hemisphere.
A pretty but rather ordinary spiral galaxy in our southern sky, NGC 2082 is the home of some perplexing radio emissions. (Credit: Wikipedia)
The emissions coming from NGC 2082 are currently being studied at radio frequencies by the Australian Square Kilometer Array Pathfinder (ASKAP), the Australian Telescope Compact Array (ATCA), the Parkes Radio Telescope along with visible light observations by the Hubble Space Telescope. What the Australians have found is a strong point source some 20 arcseconds from the center of NCG 2082 that has been given the designation J054149.24-61813.7. So far the observations of J054149.24-61813.7 tell us more about what the object isn’t that what it is. Looking at the chart below, which shows the spectral index of J054149.24-61813.7 it can be seen that the object’s power emissions as a function of frequency is pretty constant, unlike those a pulsar or supernova remnant.
The source of the radio emissions in NGC 2082 is offset from the center of the galaxy so it probably isn’t an Active Galactic Nuclei (AGN). So what is it? (Credit: Balzan, Filipovic et al)Spectra of the emissions source indicate that it is something different from those sources we already know about. So what is it? (Credit: Balzan, Filipovic et al)
In fact the flatness of J054149.24-61813.7 indicates that the radio emissions are thermal in nature, something like an AGN. However looking at the optical image above, taken by Hubble it can be seen that J054149.24-61813.7 is not at the center of NGC 2082 and in the close up lower left there does not appear to be any visual counterpart to the radio emissions. So, for the moment at least astronomers have a mystery on their hands and if further observations fail to find some clear link to a known type of radio source, perhaps a new species of object has been found for our astronomical zoo.
It is a real zoo out there. Galaxies come in all sizes and shapes so astronomers have to figure out some classification scheme just to start to understand them. (Credit: Galaxy Zoo)
Not that we aren’t still discovering new details about the strange astronomical objects we already know about. Take neutron stars for example, those ultra dense objects who are the remnants leftover after supernova explosions, stars with the mass of our Sun crushed down to the size of a city. Neutron stars have gotten some press over the last few years because the first detection of gravity waves came from the merger of two neutron stars, see my posts of 17 April 2017 and 7 October 2017. Now a multi-disciplinary team of scientists have combined their observations and theories to produce a much more detailed model about the structure of neutron stars.
When I was in college it was thought that neutron stars were so densely packed that they couldn’t have any internal structure. The Universe however thought differently. (Credit: Innovation News Network)
The study was led by theorists from the Technical University of Darmstadt in Germany and Utrecht University the Netherlands but it includes astronomical observations of neutron stars by radio and visible telescopes along with X-ray satellites. Also included were the results of heavy ion collision experiments conducted at Brookhaven National Labouratory in the US.
Once the most powerful particle accelerator in the world Brookhaven National Labouratory’s scientists still manage to do cutting edge science. (Credit: Stony Brook University)
Those experiments were especially central to the modeling of neutron stars because, unlike the particle collision experiments performed in the Large Hadron Collider at CERN the collisions at Brookhaven are of entire gold nuclei being smashed together at velocities near that of the speed of light. That makes the conditions at Brookhaven much closer to the conditions inside a neutron star.
When two gold nuclei collide in Brookhaven’s accelerator conditions very similar to those deep inside neutron stars are generated. (Credit: Flickr)
By combining the data from nuclear experiments here on Earth with observations of objects thousands if not millions of light years away the researchers hope to develop techniques for modeling many of the strange objects in the astronomical zoo. A multi-disciplinary approach combining astronomical data with the results of Earth bound experiments along with the latest theories, all in order to better understand our Universe.
Finally, in order to prove that the theoretical models they’ve developed are correct, astronomers have to compare the results of those models to observations of actual astronomical objects. That’s what astronomers at the University of Arizona are doing with the star VY Canis Majoris, a red supergiant that is considered to be the largest known star in the Milky Way.
The constellation of Canis Major (the Big Dog) contains Sirius, the brightest true star in our sky. The big dog also contains a lot of other interesting objects
Red giants like VY Canis Majoris have used up all the hydrogen fuel they initially possessed and are now using the helium produced by hydrogen fusion as their fuel. This change requires the core of the star to greatly heat up which causes the star’s outer atmosphere to expand, turning them into giants like Betelgeuse or Antares or VY Canis Majoris. In fact VY Canis Majoris has probably used up most of its helium fuel and may be getting very near the absolute end of its life.
Huge but cool, Red Giant stars have used up their hydrogen fuel and are approaching their end of their lifespan. (Credit: Forbes)
Exactly how red supergiants end their lives is something of a controversial subject right now. It was thought that red giant stars exploded as supernova, leaving only a neutron star or back hole as a remnant but lately there has been evidence of the cores of some red supergiants simply collapsing into black holes without exploding. The astrophysicists at the University of Arizona hope to resolve some of this debate by comparing their models to VY Canis Majoris.
Current thinking is that a red giant will become a neutron star or black hole by going supernova. A few astrophysicists however think that some could simply collapse without exploding. (Credit: New Scientist)
VY Canis Majoris is an excellent candidate for this study not only because it is simply the biggest star we know about but because, at a distance of 3,000 light years away it is also relatively nearby. That closeness will allow better, more detailed observations of the conditions on VY Canis Majoris to be made, enabling a more precise comparison to be made to the model. These are just a few of the techniques astronomers and astrophysicists use to study the many species of astronomical object that make up the cosmic zoo that is our Universe.
Every field of scientific research has its own ‘highest honour’ the award that is given to those researchers who have made the greatest contribution in that field. For Physics, Chemistry and Physiology that award is of course the Nobel Prize but for Mathematics the highest honour is the Fields Medal, which are awarded just once every four years by the International Mathematics Union. The Fields Medals also differ from the Nobel in another way because they are given, not to older mathematicians for a lifetime of achievement but to mathematicians under the age of forty who are currently doing important and impressive work.
Although not so well known as the Nobel Prize the Fields Medal for Mathematics is every bit as highly regarded among scholars. (Credit: The Indian Express)
This year the Union announced on July 5th that they had chosen four young mathematicians for the award. The winners are Maryna Viazovska of the Swiss Federal Institute of Technology in Lausanne, aged 37, Hugo Duminil-Copin, 36 of the Institut des Hautes Études Scientifiques near Paris France, James Maynard, aged 35 of the University of Oxford in England and June Huh of Princeton University in New Jersey, USA, aged 39.
Only the second woman to be awarded the Fields Medal Maryna Viazovska is a numbers theorist who hails from the Ukraine but is currently working at the Swiss Federal Institute of Technology in Lausanne. (Credit: Nature)
Maryna Viazovska is only the second woman ever to receive the Fields Medal and she did so for her pioneering work in the stacking of equal sized spheres in dimensions higher than three. This problem of how to most efficiently stack spheres, sometimes also known as stacking cannonballs, was first considered by the great mathematician and physicist Johannes Kepler. After considerable study Kepler decided, but couldn’t rigorously prove that the way soldiers stacked their cannonballs was the most efficient but the problem remained unsolved until mathematician Thomas Hales at the University of Michigan succeeded in 1998 with a 250 page proof.
The most efficient way to stack cannon balls may seem trivial, but a rigorous proof was not completed until 1998. Now mathematicians are trying to solve the problem in dimensions higher than 3! (Credit: International Mathematical Union)
In the years since Kepler mathematicians have become interested in spaces with more dimension than the normal, like the four dimensions of Einstein’s space-time. As you might guess problems like stacking spheres become more difficult with each added dimension. Back in 2016 Doctor Viazovska succeeded in finding the best solution in eight dimensions, calling her arrangement E8. Then, only a week later and with the help of four other mathematicians she used E8 to find the solution in 24 dimensions.
One page of Doctor Viazovska’a proof for 8 dimensions. It takes years of study and experience to be able to understand such complex mathematics. (Credit: YouTube)
Was it just luck that the solution in 8 dimensions allowed her to quickly find the solution in 24 dimensions? Doctor Viazovska doesn’t think so, she’s certain that there’s a connection and if she can find out what that connection is it may lead to more solutions in other dimensions.
How mathematics works in dimensions higher than the 3 we are aware of is a very hot topic right now. (Credit: Quora)
Meanwhile at Oxford University James Maynard is one of many mathematicians over the years who have fallen in love with prime numbers, those numbers like 7, 11 or 29 that can only be evenly divided by themselves or 1. Doctor Maynard’s work concerns the famous twin prime conjecture. That’s where, once you find a prime number, let’ say 11, the number just two later 13 is also very often another prime. This pairing has been known for centuries and as far as we know, goes on forever. (Remember since all even numbers can be divided by two, that makes two itself the only even prime, all other primes are odd.)
Oxford University’s James Maynard right where every mathematician wants to be, in front of a blackboard solving a problem. (Credit: YouTube)
As the numbers get bigger the density of primes gets smaller, for example there are 24 prime numbers between 0 and 99 but only 14 between 900 and 999. Despite the growing space between them in 2013 a mathematician named Yitang Zhang at the University of New Hampshire was able to prove that there was an infinite number of prime pairs and that the separation between them was always less than 70 million.
Prime numbers (Red) and Composite number (Blue) between 0 and 100. (Credit: Study.com)
Extending Doctor Zhang’s work what Doctor Maynard has succeeded in doing is to reduce that separation to less than 600. Additionally Doctor Maynard was able to show that there are an infinite number of primes that do not end in a 7. One more little piece in the puzzle of the most interesting group of numbers there is.
Currently the record holder for the largest Prime Number. Just thinking about a number that large makes my head spin. (Credit: Steemit)
On the other hand Doctor Hugo Duminil-Copin is a little more practical, in fact during college he had difficulty in deciding whether to be a mathematician or a physicist. Doctor Duminil-Copin’s research deals with the mathematics of what are known as phase transitions, a very complex subject indeed. Phase transitions are sudden, large-scale changes in the characteristics of a material, such as when liquid water freezes into ice.
Hugo Duminil-Copin having fun. (Credit: Institute des Hautes Etudes Scientifiques)
Phase transitions are also important in the magnetic properties of materials. Consider an ordinary bar magnet made of iron for example. The reason why a bar magnet is a magnet is because each of the atoms of iron in the bar is itself a tiny magnet, and if enough of those atoms are aligned in the same direction then the entire bar will become a magnet.
A piece of Iron or other magnetic material consists of millions of tiny Ferromagnetic Domains that normally point in many different directions, canceling each other out. In the presence of an external magnetic field those domains will line up, increasing the strength of the external field. This is a phase transition mathematically similar to the freezing of water into ice. (Credit: Material s Science and Engineering)
However, if that bar magnet is heated, then at a certain temperature, known as the Curie temperature, the atoms will start to alter their orientation, they will start to point in random directions once again and the bar will lose all of its magnetic properties. Also, if a bar of iron at a temperature above the Curie temperature is placed in an external magnetic field the atoms will line up and then, if the bar is cooled back below the Curie point, the atoms will freeze in place and the bar will then become a permanent magnet.
Above its Curie temperature the atoms in a magnetic material become so energetic that they can no longer maintain the lining up that makes a permanent magnet. (QS Study)
The standard model for this phase transition from non-magnet to magnetic, and vice versa, is known as the Ising model after German physicist Ernst Ising who solved the one dimensional version of the problem in 1924. The two dimensional version of Ising’s model wasn’t solved until 1944 and the three dimensional version, obviously the one physicists are most interested in, has never been exactly solved. To date only approximate solutions, often generated by computers, are available, but these approximations leave several very important questions unanswered.
What Doctor Duminil-Copin has done is to connect the problem of magnetic phase transitions to the better understood process of percolation of a liquid through a porous material. By doing so Doctor Duminil-Copin was able to show that some of the characteristics of the two dimensional Ising model are still true in three dimensions, in particular that while the phase transition may be rapid, it is still a continuous process, not a discontinuous jump like water into ice.
As a kid I have to admit that I was fascinated by how the old fashioned coffee Percolator worked. Letting hot water drip through coffee grounds they dissolve some of the coffee flavour. (Credit: Homegrounds)
Finally when June Huh was growing up in California and South Korea he never expected to become a mathematician, in fact he wanted to become a poet. When his writings failed to get published however he decided to major in physics and astronomy at Seoul National University, hoping to become a science writer. In his senior year of college however he met a previous winner of the Field’s Medal, Doctor Heisuke Hironaka who was teaching a course in algebraic geometry. It was that course that turned Doctor Huh into a mathematician.
June Huh at the blackboard. Mathematicians just have all the fun! (Credit: The Korea Economic Daily)
Doctor Huh’s field of research is known as combinatorial analysis, basically studying the different ways that a number of objects can be put together to form a single system. One well known method of calculating these combinations replaces each object in the system with a colour and considers the colour combinations using a set of functions called chromatic polynomials. By calculating these polynomials mathematicians gain insight into the possible combinations of a set of objects and Doctor Huh has found success in his calculations by using some of the tools he learned in algebraic geometry from Doctor Hironaka.
How many different, three letter words can you make out of A, B, and C! Well to do that problem in combinatorial analysis you might want to use a Tree Diagram. (Credit: ResearchGate)
So that’s a brief glimpse at the work of this year’s Field’s Medal winners in Mathematics. Each recipient in their own way is extending of boundaries of mathematics and just simply giving us a better understanding of the way things work.
I’m certain that by now everyone reading this post has seen those first four images taken by the James Webb Space Telescope (JWST) that were released by NASA on July 12th. The pictures are certainly beautiful, easily evoking the awe and sense of mystery that the Universe deserves, and it’s been reported that when NASA’s Chief Astronomer first saw them he was almost brought to tears. The question is, are they really that much better than the images provided by the Space Telescope (HST) and what new wonders of the Universe will JWST reveal that HST simply couldn’t.
The very first image pubically released by the James Webb Space Telescope (JWST) was a repeat of Hubble’s famous ‘Deep Field’ image showing thousands of galaxies from more than 10 billion light years away, and therefore more than 10 billion years ago. (Credit: NASA)
Let’s just start by comparing the size of the two telescopes and for any telescope the size that matters most is the area of the primary objective, the big lens or mirror that gathers in light for the telescope. The more light it gathers the dimmer the objects that any telescope can see. For the HST the main mirror was a nice circle with a diameter of 2.4 meters giving it a collecting area of about 4.5 m2.
JWST (l) and HST (r). They may not look very much alike but while HST has already revolutionized our view of the Universe and there’s little doubt JWST will do the same over the coming years. (Credit: NASA)
Calculating the area of JWST’s objective is a bit more challenging because JWST actually has 18 hexagonal mirrors each of which can have its orientation adjusted in order to maximize the light gathered by them all. The total collection area for JWST works out to around 28.1 m2, so JWST can therefore collect about 6.25 times as much light as HST. That increase in light gathering alone will allow JWST to see things in the Universe that HST simply couldn’t.
JWST’s mirror size (r) may not be a easy to calculate as HST’s (l) but it’s bigger and will allow even dimmer and farther distant objects to be studied. (Credit: NASA)
JWST is about more than just size however for the telescope has been designed to look at the Universe not in visible light but rather in the infrared portion of the electromagnetic spectrum. And in order to see in the infrared JWST had to be placed, not in an orbit around the Earth but at a position 1.5 million kilometers away from our planet called the Lagrange 2 or L2 point where the gravity fields of Earth and the Sun perform a balancing act that will keep JWST at the same place relative to the Earth. At that distance the infrared light emitted by the Earth is more manageable.
JWST will be positioned at a point known a Lagrange 2 or L2 where the combined gravities of the Sun and Earth produce a stable orbit about 1.5 million kilometers from our planet. (Credit: BBC Sky at Night Magazine)
To really protect itself from infrared light from both the Earth and Sun however JWST has been provided with a sunshield the size of a tennis court. Thanks to its sunshield the telescope and instruments of JWST will be kept at a temperature lower than -223.2 degrees Celsius. That low temperature will allow JWST to see well into the infrared, again seeing objects that HST never could.
JWST’s Sunshield willprevent the heat of the Sun from effecting delicate instruments, keeping those instruments at a cool -223.2 degrees Celsius. (Credit: NASA)
That’s important because astronomers are currently interested in four areas of astronomy that can only be studied in the infrared. One of these areas is the atmospheric composition of all of the extra-solar planets that have been discovered over the last 20 years. The chemical elements present in a planet’s atmosphere can tell us a lot about its suitability for life. The old Star Trek line about an ‘Oxygen, Nitrogen atmosphere’ is really true, such planets are more hospitable for life and NASA is very excited about the possibility of finding such a planet. Since a planet is much cooler than its sun the spectral lines of the chemicals in its atmosphere can only be studied in the infrared. In fact JWST has already begun this effort by making its first images of the TRAPPIST-1 system.
The first planet observed by JWST was WASP-96-B and the spectra of the planet’s atmosphere indicates that there is water vapour there. (Credit: NASA)
Another area where the infrared has become important is in the stellar nurseries where stars are born. You remember the famous HST image of ‘the fingers of creation’ showing a huge gas cloud with several big and bright baby stars that have just begun to shine. The problem with the HST images is that the gas clouds forming the stars are opaque in visible light and end up obscuring the actual birth of the stars. That interstellar gas is transparent in the infrared however so the JWST will be able to see right through them to get a much closer look at the very earliest stages of a star’s life.
HST’s famous image of the ‘Pillars of Creation’ (l) and JWST’s version (r). JWST can see right through the gas clouds to where the stars are being born in greater detail! (NASA)
Perhaps the most important reason for the JWST being designed to operate in the infrared is because of the expansion of the Universe and how it causes the light from the furthest galaxies and stars to be red shifted. This phenomenon is known as the Doppler shift and it’s the same thing that causes a police siren to have a higher pitch when it’s coming towards you and a lower pitch as it’s moving away.
HST’s ‘Deep Field’ (l) versus JWST’s (r) these are galaxies being born 10 billion years ago. Is it any wonder that JWST has astronomers excited. (Credit: My Modern Met)
Since the entire Universe is expanding, the galaxies are moving away from each other, so the Doppler effect causes the light from distant galaxies to become red shifted. Since the farthest galaxies are also the oldest, because it take so long for their light to reach us at the speed of light, the light from the first galaxies to form is actually shifted all the way into the infrared.
Because of the Doppler Shift the light from the earliest galaxies is shifted all the way into the infrared where HST and ground based telescopes cannot see them. That’s perhaps the most exciting aspect of JWST because in some ways we have no idea just what it might find. (Credit: Sketchplations)
That limitation meant that HST could only see galaxies as far back as one billion years after the Big Bang, but it is expected that JWST will be able to see back to 300 million years after the Big Bang, a time when most theorists think the first stars were forming. In that way JWST will help resolve some of the question we have about how the Universe went from the enormously hot fireball of the Big Bang to the galaxies and clusters of galaxies we see today.
Because of the expansion of the Universe HST cannot see anything further back than 1 billion years after the Big Bang but JWST will see further, back to 300 million years after the Big Bang. (Credit: ZME Science)
Finally, in just the last few years astronomers have discovered the first few Brown Dwarf stars, objects that do not have enough mass to ignite hydrogen fusion like a true star but that are much larger than any planet, see my post of 22 September 2021. As Brown Dwarfs continue to contract however they do get warm, and the energy released by that contraction is emitted as infrared light, just perfect for the JWST to observe. At present only a very few Brown Dwarfs are known but it is hoped that JWST will find more, enough for us to learn more about their nature and enough for us to estimate how many there are out there wandering between the real stars.
Brown Dwarfs are a barely studied class of celestial objects because what little light they emit is in the infrared. It is hoped that JWST will allow us to learn a great deal more about these objects. (Credit: Earthsky)
That’s just a brief overview of what astronomers hope to learn by using the JWST. Who knows however, perhaps ten, fifteen years from now the thing that JWST is best known for may be something that we can’t even imagine now.
Whether you call it Global Warming or Climate Change it’s an obvious fact that environmental conditions throughout the world are getting worse. And as the climate changes it is having an effect on almost every aspect of human life, even archaeology. Here are a couple of stories about how those changing conditions are actually helping archaeologists in their efforts to study the ancient past.
Human caused Global Warming is an undeniable fact, but could it actually be of benefit to the science of Archaeology? (Credit: Wikipedia)
One of the clearest signs of climate change is the severe and persistent droughts that are happening in many places across the globe. The dry conditions in western North America may get the most news coverage but the droughts in eastern Africa and the Middle East are every bit as brutal. As in western North America the lack of rain has led to thousands of square kilometers of arid soil, dried up riverbeds and historically low levels in lakes and reservoirs. The emptying of those rivers, lakes and reservoirs is now unveiling land that had been underwater for decades if not centuries or more and in the Middle East that land could have been the site of ancient human habitations dating back to the very beginnings of civilization.
The two rivers of the Tigris and Euphrates have supplied many civilizations of the past with the water they needed to exist in that arid part of the world. Today the Mosul Dam on the Tigris supplies Iraq with much of its water and electric power as well. Thanks to Climate Change water levels in the Mosul reservoir have dropped to the lowest amounts ever seen. (Credit: Landsat Image Gallery – NASA)
That’s exactly what happened recently at the Mosul reservoir, a part of the Tigris River system in northern Iraq. The prolonged drought has dropped water levels in the reservoir so much that an ancient city has appeared like magic along the banks. As quickly as the remains of scores of buildings were discovered back in January of 2022 a team of Kurdish and German archaeologists descended on the site to investigate and study the remains. Working swiftly the researchers gathered and documented what they could before the annual spring rains resubmerged the site.
As the water level in the Mosul reservoir has dropped an ancient Bronze Age city has risen from the waters making the archaeologists happy if not anyone else! (Credit: 9GAG)
What the archaeologists found was a large urban complex complete with defensive walls several meters high, a palace and several other large buildings dating to the late Bronze Age, ca. 1550-1350 BCE. At that time the region around the reservoir was a part of the Mittani Empire, one of the many city-state based powers that existed in Mesopotamia during the Bronze and Iron ages. The archaeologists even think that the site could be the city of Zakhiku an important center of Mittani culture that was destroyed in an earthquake around 1350 BCE.
One of the many now forgotten nations that existed in Mesopotamia, Mitanni was a great power in its day. (Credit: Weapons and Warfare)
While the archaeologists unearthed a large number of artifacts during their two-month excavation probably the most important discovery was the unearthing of ten ceramic jars containing more than 100 cuneiform tablets. Those tablets are now awaiting deciphering and who knows what information they could contain, whether it be the history of the city or just lists of stored agricultural products like grain or livestock.
Some of the Cuneiform tablets found at the city in the Mosul reservoir. Who knows what ancient secrets they will reveal when translated. (Credit: Euronews)
After two months of excavations the site was carefully protected by the archaeologists before the water level in the reservoir covered it once more. The buildings and walls were covered with tight fitting plastic sheets and held in place by a layer of gravel. These precautions will hopefully preserve the site until the next time the water level at Mosul gets low enough for further excavations to be carried out, which, thanks to climate change could be very soon.
As the annual spring rains caused water levels to rise the archaeologists covered the ancient Mitanni city in order to preserve its remains until the next time climate change induced drought brings it back to light. (Credit: ZME Science)
Not coincidentally the same thing is happening in western North America where drought has caused the water level in many large reservoirs to drop to record levels. The land that is being revealed is yielding surprising and in some cases grisly remains from the past. At lake Meade near Las Vegas for example the bodies of three individuals have been found who are thought to have been murdered and dumped in the lake back in the 1950s-60s when mobsters fought over the casinos of Nevada.
Lake Meade, the largest artificial lake in the US and source of water for tens of millions of people, is disappearing before our eyes. (Credit: Boulder City Review)
More important, if not more salacious, are the archaeological sites that have reemerged from Lake Powell, also along the Colorado River. In pre-Columbian times that region of what is now Utah was inhabited at different times by native Americans of the Pueblo, Paiute, Hopi and Navajo peoples. When the dam for Lake Powell was built it was feared that dozens if not hundreds of ancient sites had been lost forever. In fact archaeologists of that time organized a hasty survey of those sites called the Glen Canyon Project in the hopes of recording some of the remains there before they disappeared forever.
For thousands of years the Native American peoples of the desert southwest built small cities along the fertile valley of the Colorado River. Some of this archaeological sites were submerged when the dams were built that formed Lake Meade and Lake Powell. (Credit: Grand Canyon Trust)
Turns out it wasn’t forever. Thanks to climate change and the severe drought throughout the western US about one quarter of the sites cataloged in the Glen Canyon survey have already been rediscovered and are currently being studied. The archaeologists involved in the research have been mostly astonished by how well preserved the sites are and are hopeful that this time the evidence of the past will be adequately investigated.
One of the archaeological sites recently revealed by the falling water levels of Lake Powell. Dozens of such sites have already been re-discovered and hopefully many more can also be surveyed. (Credit: KNAU)
We all have heard the old saying, “Every cloud has a silver lining”, well perhaps the reemergence of ancient human habitations once submerged in modern reservoirs may be the silver lining of climate change, but that cloud around the silver lining is awfully big and black.
Wet Dress Rehearsal (WDR) for a space system is a test intended to see if the rocket and all of its auxiliary systems can be fully loaded with fuel and oxidizer and if all of the electrical systems can be powered up and readied for flight. For the Space Launch System (SLS) the WDR also includes all the systems aboard the Orion man capable space capsule. In fact the WDR includes all of the steps that take place in an actual launch countdown right up to the last few seconds before ignition, usually about T minus thirty seconds. Back in April the Space Launch System, the rocket that NASA plans on taking American astronauts back to the Moon, failed to complete its WDR several times and had to be returned to the Vehicle Assembly Building (VAB) for repairs.
The Wet Dress Rehearsal (WDR) for the Space Launch System (SLS) with its Orion Man capable capsule. (Credit: NASA)
Those repairs were soon accomplished and once again the SLS was rolled out to Pad 39B at Kennedy for a second attempt at the WDR, which began on the 18th of June. Although there was a problem during the test with a leaky quick disconnect valve on the hydrogen intake to the rocket’s core stage the NASA engineers were able to work around the problem. The rocket itself went through the test without any difficulty and the WDR was concluded on June 20th and officially declared a success. According to the Artemis Mission Manager Mike Sarafin, “I would say we’re in the 90th percentile.”
The WDR now completed the SLS has been rolled back to the Vehicle Assembly Building (VAB) for final preparations before launch, now scheduled of August 19th! (Credit: SciTechDaily)
So the question was, is that good enough? After all of the years waiting for the SLS to be completed and tested, after all of the schedule delays and cost overruns, is 90% on the final exam good enough?
NASA hopes so, they have given the SLS a go ahead for a late August, early September launch of the Artemis 1 mission. A tentative launch date of August 19th has been announced. Although that flight will be unmanned it will be the first time since the Apollo program ended in 1972 that a man capable spacecraft will leave Earth orbit and travel to the Moon. And if Artemis 1 is successful then a manned Lunar orbiting mission can be expected to launch sometime in 2024.
Like the Apollo 8 mission in 1968 the Artemis 2 mission will be a Lunar Orbiter without a vehicle capable of landing. (Credit: eBay)
Meanwhile there is a lot of news relating to robotic space exploration happening as well. One disappointing announcement was made on June 24 of 2022 concerning NASA’s Psyche mission to study that metal rich asteroid. Because of delays in the delivery of the spacecraft’s software and specially designed test fixtures the robotic probe will not be ready in time to launch during its August 1st though October 11th orbital window.
The Asteroid Psyche and Psyche Space Probe. Delays in software development and testing have forced a delay in the scheduled launch of Psyche, imperiling the entire mission. (Credit: SciTechDaily)
That leaves the entire mission sort of up in the air because the Psyche probe’s trajectory was planned to use a Mars fly-by as a gravity boost in order to reach the asteroid by 2026. There are possible launch windows for both 2023 and 2024 but they are far less optimal, the spacecraft would not reach Psyche until 2029 or 2030.
The Voyager 1 Space Probe got a gravity boost from the planet Jupiter on its way to Saturn. The Psyche space probe was designed to do the same thing using Mars as its booster but because of delays in the spacecraft’s launch the planet will no longer be in the the correct position for the boost. That will cause Psyche’s journey to the asteroid to be much longer. (Credit: Wikipedia)
So NASA is seriously considering the possibility of using the Psyche probe to study something else in our Solar System. The question is what, and would that actually help in making a successful mission. The problem of course is money; the entire Psyche mission was given an original budget of $985 million dollars, of which $717 million have already been spent. Can the Psyche team get the spacecraft completed and ready for a launch next year and still have enough money remaining for an eight-year long mission? Or, can they quickly find another target and get everything ready with the money remaining?
There are a lot of Asteroids out there that could be studied by the Psyche space probe. Perhaps Mars could give a gravity boost to one of them? (Credit: Wikipedia)
The Psyche mission is a part of NASA’s Discovery program, which was intended to develop programs that can accomplish real space science for less than a billion dollars. Therefore it is unlikely that any more funding will be forthcoming, the program managers at JPL will just have to make do with what they’ve got.
The Jet Propulsion Labouratory in California manages most planetary robotic missions for NASA. Being a bunch of bright guys they’ll figure something to do with the Psyche spacecraft. (Credit: Caltech International Offices)
Finally, the James Webb Space Telescope has been undergoing its instrument checkout and calibration before beginning it science mission, expected to start as early as this month. There was a moment of concern on the 8th of June when it was announced that a micrometeorite had struck Webb’s C3 mirror section. Such a collision had been expected several times during the space telescope’s ten-year mission and in fact four smaller impacts had already occurred but a collision of that size so early in the mission was surprising. Fortunately it wasn’t long before the science team managing Webb were confident that the small amount of damage caused by the micrometeorite would have no noticeable effect on the quality of Webb’s images.
Computer images of the damage caused by a micrometeorite (r) to JWST’s C3 mirror. The Left view is the system as it was designed. (Credit: Space.com)
Meanwhile the astronomical community is waiting with bated breath for those images, the quality of which according to NASA’s chief astronomer Thomas Zurbuchen nearly ‘brought him to tears’. It is anticipated that the first images from the Webb space telescope will be released on the 12th of July. Then perhaps we’ll all be agreeing with the opinion of the chief astronomer.
The first four images taken by the JWST have astronomers all over the world excited about what is to come. (Credit: Universe Today)
The Hubble Space telescope has revolutionized our view of the Universe and our place in it. I think that in the years to come the James Webb Space Telescope will accomplish much the same.
I don’t know about you but I’m getting pretty tired of SF novels that are really just action / adventure / war stories set in outer space. It seems to me that outer space is just too big and life in it too rare for alien civilizations to just start fighting the instant they encounter each other. That’s exactly what ‘To Sleep in a Sea of Stars ‘ is however, one long, very long novel of battle after battle with little rhyme or reason to it.
With all of the mystery and wonder there is waiting for us in outer space why does it seem like so many SF stories are just a lot of fighting? (Credit: CBR)
It starts out interestingly enough; Kira Navarez is an exo-biologist, a member of a team of explorers who are surveying the planet Adrasteia in a distant solar system in order to ascertain whether it would make a suitable colony for human beings. Kira is on a routine mission when she stops to investigate a strange outcropping of rock and before she realizes that it is an alien structure she is infected with an alien xenomorph, a thing that is part living and part machine.
Front cover of ‘To Sleep in a Sea of Stars’ by Christopher Paolini. (Credit: Amazon)
As her team members try to remove the xeno from her several are killed by it, including her fiancé Alan. If this part of the story kinda reminds you of the beginning of the movie ‘Alien’ get used to it. A lot of ‘To Sleep in a Sea of Stars’ will remind you of a lot of other stories.
The term Xenomorph literally means ‘alien shape’ and two of the best known are the ones from the movies ‘Alien’ (l) and Predator (r). The aliens in ‘To Sleep in a Sea of Stars’ have a lot in common with these two. (Credit: YouTube)
A military starship from Earth manages to seize Kira and put her in isolation where they begin to experiment on the xeno, and Kira. Suddenly an alien spaceship appears and the two starships immediately begin fighting. During the battle Kira manages to escape and in a space pod heads back to the nearest human colony where she expects that she will again be seized by the military.
Author of ‘To Sleep in a Sea of Stars’ is writer Christopher Paolini. (Credit: Twitter)
Instead she winds up on a broken-down half-space worthy ship called the Wallfish whose crew are a ragtag bunch of misfits. You know the type, rejects from polite society but who nevertheless have a heart of gold. It doesn’t take long to figure out that the Wallfish is just a bigger version of the Millennium Falcon crewed by a dozen different versions of Han Solo.
A rogue with a heart of gold. How many such characters have seen in movies or read about in a book and how many have you actually met in real life? (Credit: StarWars.com)
Meanwhile the aliens are now attacking humanity everywhere while Kira is forced to learn how to live with the xeno, which is a sort of skin enveloping her. As she begins to learn how to control it, a process that takes an awful lot of pages, you start to think of the thing as a kind of Iron Man suit and as the story goes on Kira gains more control over it becoming more and more powerful in the process.
In the first Iron Man film Tony Stark, played by Robert Downey jr, spends 10-15 minutes learning how to use his suit. In ‘To Sleep in a Sea of Stars’ the character Kira spends almost half the novel learning how to control her xenomorph. (Credit: The Wrap)
One thing Kira discovers is that the suit, whose name is the Soft Blade, allows her to understand the language of the aliens and she begins to put together a plan to somehow use the xeno’s power to stop the war. The aliens by the way are a sort of cross between squids and arthropods that the humans begin calling Jellies. Incidentally the Jellies did not make the Soft Blade but they want it for its power.
The first Aliens in ‘To Sleep in a Sea of Stars’ are described as kind of a mixture of squids and crustaceans. Sounds icky, well its supposed to. (Credit: Vector Stock)
Before Kira can even finish formulating her plan stop the war however another alien species appears and immediately begins to attack everybody, Humans and Jellies. These newcomers are vile, ugly, half made creatures that humans call Nightmares and the Jellies call the Corrupted. I quickly began to imagine them as the army of the Dead in Game of Thrones. Again the author just seems to throw in ideas from all over the place.
Although the second set of aliens are supposed to be made up of corrupted versions of many life forms their description reminded me of the army of the dead in Game of Thrones. (Credit: Game of Thrones Wiki)
The novel goes on and on like this for more than 800 pages, battle scene after battle scene, with Kira learning how to control the Soft Blade a little better between each fight. Another annoying thing about the book is that, during every fight there’s a point where Kira thinks that the situation is hopeless, there’s simply no way out until suddenly the cavalry arrives in the nick of time, or she somehow discovers a new power that the Soft Blade has. It all gets a bit redundant after a while.
In ancient Greek Theater they would often use a hoist to just drop in a god like character who would solve everything. This is Deus ex Machina or God from a Machine. In modern drama the cavalry arriving in the nick of time or someone just coming up with a great idea out of nowhere serves the same purpose. (Credit: Quora)
And to top it all off, after fighting her way across half the galaxy the author decides to get kinda mystic at the climax as Kira uses the Soft Blade’s true powers to sort of just heal everyone. Really, the ending left me feeling like, you couldn’t have done that about 700 pages ago?
After 700 pages of blood and gore Christopher Paolini suddenly decided to get metaphysical, really???? (Credit: Audible)
Still, if you are the sort who enjoys a good laser battle with starships firing anti-matter bombs at each other rather than a thought-provoking story you may enjoy ‘To Sleep in a Sea of Stars’. Be warned however, it is a long story with a lot of redundancy.
Solar energy derived from photovoltaic cells is of course one of the technologies that environmentalists hope will replace fossil fuels as a primary source of power for human society. In order to do that solar cells need to be as efficient as possible in converting the light of the Sun into useful electricity. That’s why for decades now scientists and engineers have worked and struggled to increase the efficiency of photovoltaic materials.
With all of the ways we’ve developed to generate clean, green energy why are we still getting 90% of our energy from fossil fuels, ‘Cause it’s cheaper that why! (Credit: Greenesa)
But visible light is not the only kind of electromagnetic (EM) energy; there are others such as radio waves, X-rays and Ultraviolet radiation. One kind of EM energy that could also be gathered as a power source is infrared (IR) radiation, also just known as heat radiation. There are many sources of heat both natural; such as geothermal, and industrial, like furnaces, that could be harnessed for their energy if there were a more efficient technology available.
Infrared light is just the heat that many things in the world generate. That light is energy, energy that we could use if we develop the technology to capture it. (Credit: Herschel Space Observatory)
Now there is, for the engineers at the National Renewable Energy Labouratory (NREL) have recently tested a thermophotovoltaic cell that demonstrates a 40% efficiency at converting IR energy into electrical power. That figure is fully 8% better than the previous record of 32% and is actually better than the efficiency of conventional boilers and steam turbines that are currently the most common technology for producing electricity in fossil fuel and nuclear power plants.
IR imaging inside a power plant. That light you see is energy going to waste. Capturing that energy will by itself make power plants more efficient and help cut down on polluting emissions. (Credit: Dornier Group)
The new type of photocells are manufactured in much the same way that the better known visible photovoltaic cells are except that they possess two light absorbing layers and the entire cell is backed by a reflective layer of gold while sitting on a heat sink to prevent overheating, which decreases efficiency. The version tested is optimized to absorb heat radiation from sources at a temperature of 2,400ºC but that can be adjusted by altering the thickness of the various semi-conductor layers. Thermophotovoltaic devices also have the advantage of not having any moving parts, which both makes them longer lasting while reducing maintenance costs.
Thermophotovoltaic cell developed at MIT and NREL. With no moving parts such a cell could provide years to energy generation. (Credit: Engadget)
The team at NREL hopes that adjustments to the reflective gold layer can increase efficiency further, to perhaps as high as 50%. Nevertheless the development of thermophotovoltaic cells is one more step in our efforts to make better, more efficient use of the energy we already have, one more way of reducing the amounts of CO2 emitting fossils fuels we burn.
Construction of the thermophotovoltaic cell. The back mirror is one of the key elements to the device’s efficiency. (Credit: EnergyPost.eu)
Of course the emission of CO2 into the atmosphere is not the only massive source of pollution we humans are currently generating, there’s all of that non-degradable plastic as well. Now in many ways plastics are a miracle of modern science and have improved our lives so much, we mustn’t forget that. They are cheap, can be made in an almost infinite variety of forms, are long lasting and at least initially biologically sterile.
Plastics are wonderful, we use them is thousands of ways. And then, when we’re done with them we just throw’en away. Where’s the harm in that???? (Credit: Plasticseurope.org)
The problem with plastics is that they don’t go away; technically they don’t decay chemically, not for hundreds or thousands of years. And since we use so much of them, and we’re only recycling a small fraction of what we use, they are really starting to pile up everywhere. Also, although they don’t decay chemically they will break down mechanically into smaller and smaller pieces of plastic, pieces that are getting into the biosphere, into the very flesh of plants, fish, birds, mammals and even us!
How harmful are microplastics? Well they killed this poor little fella, and how much longer before they start killing us? (Credit: Science Learning Hub)
Because of this scientists have for the last several decades been searching for better ways to recycle or break down plastic into its chemical components so that they can be reused or absorbed back into the environment. Those chemicals that can break down plastics are a special class of enzymes known as polyester-cleaving hydrolases and in 2012 an enzyme called LCC was discovered in Japan that showed some promise as a ‘plastic eater’.
The basis of all plastics is a polymer, basically just a long chain of identical molecules. Such polymers can be very stable, lasting for years if not centuries before breaking down. (Credit: Cosmos Magazine)
Now chemists at Leipzig University have found a new enzyme that has been found in tests to breakdown a common form of plastic twice as fast as LCC. The researchers, led by Dr. Christian Sonnendecker actually discovered the new enzyme, which they have named PHL7, while investigating the chemical reactions taking place in compost heap in Leipzig itself.
Dr. Christian Sonnendecker in his lab in Leipzig. (Credit: Phys.org)
In addition to breaking down plastics faster than LCC, the chemicals that remain after PHL7 has done its work are the exact same chemicals, terephthalic acid and ethylene glycol, from which the plastic was made in the first place, which means the chemicals can then be used to make brand new plastic, a completely closed cycle, the ultimate goal in recycling.
For billions of years life on Earth recycled everything, nothing went to waste and the only input to the cycle was energy from the Sun. We need to learn how to do the same. (Credit: Recycle Montana)
And speaking of plastics we can all do our part in trying to reduce the amount of plastics we use once and then thrown away, plastic drinking straws being one of the most obvious examples. Here in the US something like 200 million plastic straws are used every day, used once and then just tossed away. Each individual straw may seem like a very small thing, a harmless thing but 200 million a day adds up and the results are easy to see anywhere trash accumulates.
Straws may seem small and unimportant but they add up! (Credit: Vonastraws)
Also the type of plastic used for most straws is of a kind that isn’t easy to recycle, and again like all plastics it doesn’t decay in the environment. One way to solve the problem all those straws is to make them out of a material that is biodegradable, a substance that bacteria and other living things can break down and use for food, straws that can be composted and become fertilizer.
If only the plastic items we use everyday could become this after we’re done with them. (Credit: Better Homes and Gardens)
Now a new company called Loliware has done just that using seaweed as their basic material. The company, based in California’s Silicon Valley, has developed a process that takes dried seaweed and mills it down. Then, after combining it with minerals and colouring, the mixture is formed into seaweed pellets that can be used in the same machines that are used to produce ordinary plastic utensils. The look and texture of the seaweed utensils are very similar to their plastic counterparts and because much of the same equipment is used in their manufacture the cost is only slightly higher.
Straws made from seaweed! Once used they can even become fertilizer for your lawn! (Credit: Ecowatch)
So with all of the new, environmentally friendly technology being developed by so many creative scientists and engineers why does it seem as if we’re continually loosing ground in the fight to clean up our planet. Vested interests and simple inertia are the main causes. The oil industry is simply making so much money off of disposable, single use plastics that they can keep prices low, making it hard for biodegradable alternatives to gain a competitive advantage.
And with the Supreme Court now limiting the ability of the EPA to regulate the emissions of power plants it’s going to even more difficult to stop polluters from poisoning our planet. (Credit: Cleveland.com)
Inertia is even more of a problem. We’ve been doing the same things for so long and we just don’t see any reason to change, particularly change to a more expensive substitute. We humans can become so used to the things going on around us that even the massive buildup of CO2 and plastic trash throughout the world we feel is just a part of life, nothing for us to worry about. But the damage we are doing to the only planet we have is real and it’s getting worse all the time. We need for all of us to recognize the danger and if not do something to help then at least get out of the way!
It was on the 24th of June in 1947 that Idaho businessman and private pilot Kenneth Arnold was flying near Mount Rainier in Washington State when he observed nine objects flying in tandem above the hills and mountains. Reporting his sighting Arnold would describe the objects as being shaped like a pie plate cut in half with a convex front and a concave rear. He also described the motion of the objects as they flew along as ‘like a saucer skipping across water’.
Kenneth Arnold, the man who did not intentionally coin the term ‘Flying Saucer’ holding a picture of the aircraft he saw. (Credit: Seattle Times)
So was born the ‘Flying Saucer’ craze that even today has not let up; tens of thousands of similar sightings have been reported in the years since 1947 and probably many more have gone unreported. Because very few reported sightings actually looked like saucers, most are simple lights in the sky that ‘behave strangely’, a technical term was soon created where the things would become known as ‘Unidentified Flying Objects’ or UFOs.
What everyone knows a flying saucer should look like. Of course this one was ‘Made in Hollywood’. (Credit: RetroZap)
In many ways Arnold’s original sighting was typical of a ‘good’ UFO report. Arnold was a well regarded, reliable citizen, a skilled pilot with 9,000 hours of flying time. The report he gave contained many details of the objects, their number and shape, where they were seen in the sky, their direction and approximate ‘angular velocity’. (That’s important in UFO sightings because if you don’t know how far away an object is you really cannot say how big it is or how fast it’s moving, you can really only estimate its angular size and angular velocity.) Sightings with that kind of detail are usually either solved or if they remain unsolved they constitute strong evidence that something very unusual happened.
Arnold’s report. Competent observers giving details accounts of their sightings are still, after 75 years the best evidence that something really is out there but exactly what, no one knows. (Credit: New York Times)
In the early days of the UFO phenomenon there was considerable debate as to exactly what UFOs were. Right from the start alien spacecraft held the lead but secret Russian aircraft and even secret American aircraft were strong contenders. In time of course the Russians and Americans fell out of favour and today anyone who sees a UFO immediately knows it’s aliens come to Earth. Which if you think about it means that they shouldn’t really be called Unidentified should they?
Yes, the US Air Force did actually experiment with flying saucers but the program was dropped because, wait for it, they don’t fly very well! (Credit: Edwards Air Force Base)
Of course Hollywood has had a great deal to do with aliens going from being the favoured to the exclusive passengers on UFOs. After all how many movies have you seen where a Flying Saucer lands and out steps a Bug Eyed Monster or BEM, as opposed to many have you seen where a Russian or American steps out? And anytime a big Hollywood movie about Flying Saucers such as Steven Spielberg’s ‘Close Encounters of the Third Kind’ or ‘ET, the Extraterrestrial’ are released the number of UFO sightings reported triples or quadruples for the next few years.
The Mother Ship from ‘Close Encounters of the Third Kind’. After ever big blockbuster UFO movie or TV show the numbers of sightings doubles or triples. So the question is, are UFOs out there or in our minds,or maybe both? (Credit: YouTube)
There have been many attempts to try to solve the mystery of UFOs. Undoubtedly the best known of which is the US Air Force’s Project Blue Book of the 1950s and 60s. In fact the term UFO was coined by one of the leaders of Project Blue Book Captain Edward J Ruppelt. It is important to remember that Project Blue Book was never tasked with finding out what Flying saucers were. Its job, as outlined in their budget request to Congress, was to determine whether or not UFOs constituted any threat to the United States. Blue Book was closed down in 1969 but since the United States is still here, there has been no alien invasion you have to agree that UFOs weren’t that much of a threat.
The man who did coin the Term ‘Unidentified Flying Object’ or UFO was Air Force Captain Edward J Ruppelt seen here with my well word copy of this book. (Credit: UAPSG / R. A. Lawler)
There have also been several scientists who have attempted to study UFOs; perhaps the best known of these was the astronomer Josef Allen Hynek who acted as a scientific advisor to the Air Force from 1947 to 1969. It was Hynek in fact who developed the ‘Close Encounter’ system of classifying UFO reports. During his time with Project Blue Book and for many years afterward Hynek came to believe that UFOs were an important subject that needed much more attention and resources than the Air Force was willing to commit to. After leaving Blue Book Hynek would found the Center for UFO Studies (CUFOS).
Working closely with Project Blue Book was the University of Chicago astronomer Josef Allen Hynek who created the ‘Close Encounter’ classification system for UFO sightings and formed the Center for UFO Suudies. (Credit: University of Chicago)
One problem with trying to study Flying saucers is the tremendous number of bad UFO sightings, you know the type, ‘I saw somethin’ in the sky… must a been one of them Flying Saucers’. Even worse are the outright frauds and hoaxes that really make any empirical study of the subject all but impossible. Think about it, a prominent, important scientist, a Nobel Laureate let’s say, decides to investigate a famous video of a Flying Saucer. He decides that the evidence is so strong that, ‘There can be no doubt that this is a unknown phenomenon’! Only to have the video’s maker go on TV and declare it to be a fake while laughing at how he fooled a Nobel winner!
Some UFO hoaxes are easy to spot. Notice how the buildings are a bit out of focus while the saucer is really sharp???? That indicates that the saucer is actually much closer and rather small, in other the picture is a fake. Many such frauds have been created making real scientists unwilling to stake their reputation on evidence that could just be a lie! (Credit: CNET)
When scientists make measurements they do everything they can to make that data as accurate as possible, and they assume that other scientists do the same. Any scientist who is proven to have knowingly or even incompetently published inaccurate data quickly looses all of their reputation and no one will ever trust them again.
A UFO or just a hub cap thrown in the air? Strange things in the sky are so easy to fake you can’t be sure of anything when it comes to UFOs. (Credit: The Conversation)
If a scientist wants to study UFOs however they will have to trust the information provided by normal citizens, a small number of whom are only interested in publicity or sometimes even just making people smarter than them look stupid. Because of the possibility that the data coming from witnesses could be unreliable or worse, outright lies even scientists who think that there could be something interesting in UFOs won’t touch the subject and avoid making any statements regarding ‘flying saucers’.
The USA accounts for about 80% of the UFO sightings worldwide even though we have only 5% of the world’s population. So do ETs just prefer the US or are we the only country that refuses to accept the idea that something you don’t immediately recognize doesn’t have to be aliens! (Credit: The Washington Post)
Over the last seventy-five years there have been a large number of UFOs incidents that have become highly publicized. During the 1950s Flying Saucer reports even made headline news. Incidents such as the Lubbock lights in August of 1951 and the numerous radar contacts of UFOs over Washington DC during a two week period in July of 1952 forced the US Air Force to open an investigation into whether or not the phenomenon represented a threat to the security of the nation.
The Lubbock Lights were seen by hundreds of people in the city of Lubbock Texas in 1951. Turned out that they were a flight of B52 bombers practicing refueling at night. (Credit: TV Fanatic)
It was also during the 1950s that the first photo and first movie of a UFO were made. A farmer outside of McMinnville, Oregon took the first photo in May of 1950. Just three months later in August it was the manager of the Great Falls, Montana minor league baseball team however who made the first colour movie of two UFOs flying above the town. That film has been subjected to many years of analysis and even today represents some of the best evidence for there actually being something unknown flying in our skies.
Thirty seconds of film of two lights streaking across the sky of Great Falls Montana in 1950 is still some of the best evidence for UFOs. This film has been extensively studied and corroborated by other witnesses. But it’s still just two lights! (Credit: SportsLogos.Net.news
Of course the most famous UFO sighting of them all is the Roswell, New Mexico case, which grabbed headlines across the country just two weeks after Kenneth Arnold’s report. On July the 8th of 1947 the press officer at the US Army Air Core base outside Roswell, the Air Force did not yet exist as a separate branch of the military, announced that a Flying Saucer had crashed and the wreckage was in the Air Core’s possession. Just three hours later that initial report was changed to it being a weather balloon that had crashed.
The Headline that started the myth. Hours later the Army Air Corp would claim it was just a weather balloon but today even they admit there was more to it than that. What was it and will everyone ever accept the truth, who knows? (Credit: Smithsonian Magazine)
I’m not going to go into any detail about Roswell, too many lies have been told by both sides of the UFO debate for any truthful accounting of the facts to be presented now. I will just say that for the US government to have had a Flying Saucer in its possession for seventy-five years without some concrete evidence getting out is hard to believe.
Again many fakers have produced ‘evidence’ of the Roswell UFO. (Credit: KMPH)
Another aspect of UFO reports are the large number of people who have claimed to have been abducted and taken aboard the spaceships. One of the first such incidents was reported by Antonio Vilas Boas of Brazil in October of 1957. Probably the most famous UFO abduction however was that of Betty and Barney Hill who in September of 1961 were driving in New Hampshire when they were stopped by a huge floating disk and taken aboard by alien creatures where they were medically examined. It is worth noting that the Hills only remembered their encounter after suffering nightmares and seeing a psychologist who used hypnosis to ‘regain’ their memories making those memories suspect at the very least.
Betty and Barney Hill with a copy of their book “An Interrupted Journey”. It must be remembered that the Hills only remembered their UFO encounter when under hypnosis. (Credit: www.history.com)
Some UFOs sightings have been so spectacular that hundreds or even thousands of people have witnessed them at the same time. Such incidents include a Football match in Florence Italy in October of 1954 when a crowd of over 10,000 fell silent as a glowing light, traveling at high speed, came to a sudden stop directly over the stadium. Another mass UFO sighting took place in Kecksburg, Pennsylvania on the night December 9th of 1965 as a fireball passed over the town dropping debris and causing sonic booms. The likely impact area of the fireball was quickly cordoned off by the military and only years later did the government reveal that the UFO had actually been an early spy satellite returning from orbit.
The UFO that crashed in Kecksburg Pennsylvania was actually from outer space. It was an early version of a spy satellite. (Credit: Wired)
The interest and publicity generated by the early Flying Saucer reports soon inspired a few UFO researchers to begin to comb through the historical record. What those researchers discovered were accounts of strange sightings and even encounters going back centuries that were nearly identical to more modern UFO reports. Such incidents go back as far as the Old Testament in the bible where ‘Ezekiel saw a wheel’. The author Erich von Danikan even proposed in his book ‘The Chariots of the Gods’ that the deities and demons of ancient myth and legend were in fact extraterrestrial visitors who came to Earth in Flying Saucers and made contact with ancient humans.
Erich von Daniken made a lot of money from his investigations into ancient UFOs but whether or not he found any actual evidence of aliens here on Earth is debatable. (Credit: Best Buy)
The UFO phenomenon has continued until the present day. The release of TV shows or movies about aliens like ‘The X-Files’ or ‘Independence Day’ can cause an uptick in UFO sightings but they never really go away entirely, people just see strange things all the time. The publication last year of videos taken by US Navy aviators flying off of the aircraft carriers Nimitz and Theodore Roosevelt showing ‘unexplained aerial phenomenon’ has spurred new interest in flying saucers. However those same videos also highlighted the problems with the whole study of UFOs because they really provide no better evidence of just what the unknown objects are than did the Great Falls, Montana colour movie made back in 1950. That’s the plain fact, we really have no better evidence of what UFOs are than we did in the 1950s. All we really have is a large number of reliable, often trained observers who see something, and occasionally take pictures of something flying in the sky that they don’t recognize. Scientifically we’ve been stuck at the same place for seventy years.
The latest UFO flap is over a couple of short films taken by Navy Pilots of ‘something’. Really these videos are no better than the Montana film taken 72 years ago. (Credit: Wall Street Journal)
Still the recent, much publicized Navy videos have even prompted congress to take action. On the 17th of May the House Intelligence Committee began a series of hearings into UFOs in general and the UFO reports from military personnel in particular. Some of the hearings are scheduled to be held in public but others are going to be closed door for reasons of national security. Of course the true ‘UFO believers’ are going to claim that the real evidence is in the closed door hearings and the public sessions will be nothing but a cover-up. Still, you know that once congress gets involved they’ll have the whole matter sorted out in no time…yea right!
The one thing they are good at! (Credit: Radical Compliance)
Personally I’m confident that there is something out there, some unknown phenomenon. But I’m also confident that it is a natural, not extraterrestrial phenomenon. And I also think that this phenomenon should be studied scientifically, which is why I’m glad that Harvard astronomer Avi Loeb is setting up a project to gather new data about UFOs. I wish Dr. Loeb the best of luck but to be honest I don’t expect the question of UFOs to be resolved to everyone’s satisfaction during my lifetime, if indeed ever.
