Month: February 2020

Paleontology News for February 2020.

Now I’d be the first person to point out the science of paleontology is about a lot more than just dinosaurs. Dinosaurs are just one of the myriad groups of once living creatures that we only know about through their fossilized remains. Still, what kind of creature do we immediately think of when we think of paleontology? Dinosaurs that’s what! So this month’s paleontology post is all about dinosaurs.

My introduction to the science of Paleontology, many years ago! (Credit: ETSY)

Everyone knows that animals get sick just the way that we humans do. When you hear stories about swine flu or bird flu remember that those diseases are given their names because they actually came from those animals. Even extremely deadly human diseases such as smallpox and bubonic plague are actually diseases of cattle and rats respectively.

With modern instruments paleontologists can sometimes even find the telltale evidence of diseases in the fossils that they unearth. It’s actually true, Tyrannosaurids (the family of T rex) have been found with evidence of gout while osteoarthritis has been diagnosed in Iguanodons.

A recent study has been published by lead author Bruce M. Rothschild of Indiana University and the Carnegie Museum in the journal Nature. What Doctor Rothschild and his colleagues have found are lesions produced by the cancer Langerhans cell histiocytosis (LCH) in the tailbones of a duck billed Hadrosaur from Alberta Canada. The exact species of the Hadrosaur whose bones were studied could not be exactly determined because the animal’s skull was not found. 

Two tailbones of a Hadrosaur were found to possess cavities caused by cancerous tumors. (Credit: Live Science)

Now normally Langerhan cells in the body regulate the immune system but in LCH overproduction of Langerhan cells leads to the growth of benign tumors called granulomas in the bone marrow. After the death of the Hadrosaur the cancerous Langerhan cells decayed along with the animal’s normal cells so that the tumors left cavities in the dinosaur’s tailbones, cavities that could be studied using both microscopes and other instruments. Based on the evidence provided by those studies the Doctor Rothschild and his colleagues were able to determine that LCH is the closest match in form to the cavities in the Hadrosaur’s tail.

Closeup view of a tailbone. The cavity in the middle of the right view was caused by a cancerous tumor. (Credit: Live science)

Recognizing and studying the diseases that plagued animals in the past may help us to better understand how those diseases ever arose in the first place. In any case the knowledge that those animals suffered from diseases just as we do helps to remind us of one of the things that all living creatures have in common.

There’s something else that we and dinosaurs may have in common, warm blood. The possibility that dinosaurs may have evolved to have been able to maintain a warm internal body temperature has been around for about the last fifty years, and during that time a great deal of circumstantial evidence to support the idea has accumulated. Not everyone is convinced however, so each piece of new evidence strengthens the case for dinosaur warm-bloodiness.

Fossil evidence that at least some species of Dinosaurs were covered in feathers is strong support for the idea that dinosaurs were warm blooded. (Credit: NPR)

The latest discovery comes from an examination of the eggshells of cretaceous era dinosaurs in a paper published in the journal Science Advances with lead author Robin R. Dawson of Yale University’s department of Geology and Geophysics. Using a newly developed technique called ‘Clumped Isotope Paleothermometry’ the researchers measured the ordering of oxygen and carbon atoms in the wall of a fossilized eggshell as a means to determine the mother’s internal body temperature.

Hardosaur dinosaurs are know to have been good parents. The mother warming her eggs with her own body heat. (Credit: Sci-News.com)

Using this technique the paleontologists were able to measure the internal temperatures of three distinct species of dinosaurs. Troodon, a small theropod related to T rex whose body temperature was determined to be 38ºC and Maiasaura, a duck billed dinosaur whose body temperature was found to be 44ºC. The specimens for both of these species came from Alberta, Canada. The final species to have their eggshells tested is named Megaloolithus, which comes from Romania and is known only by its eggs, and whose temperature was found to be 36ºC.

Cross Sections of Dinosaur Eggshells used in the Yale study. (Credit: Sci-News.com)

Now the scientists had to be careful, remember cold-blooded means that an animal’s body temperature is the same as the ambient air around it. So if those eggs were laid on a hot summer’s day the mother’s body temperature could still have been as high as 44ºC! The researchers needed to find a control to test, the egg of a definite, known cold-blooded animal which would give a measurement of the air temperature.

Paleothermometry is one of the newest techniques that scientists have developed to glean every possible bit of information about the past from fossils. (Credit: nerdfighteria.info)

Fortunately they were able to find the necessary eggs allowing the temperature of the mother Troodon to be determined to be about 10ºC warmer than the temperature of the ambient air while the Maiasaur mother’s body temperature was 15ºC warmer. The Megaloolithus mother was also found to be 3-6ºC warmer than the air temperature. This research provides yet one more piece of evidence that dinosaurs were warm-blooded. Further advancing the argument that dinosaurs were actually more like modern birds than the ancient reptiles from whom they evolved.

Archaeology News for February 2020. Two Stories from beyond the Grave!

‘Dead men tell no tales’ the saying goes but I think archaeologists would argue with that. Much of what we have learned about the past has been obtained by studying the mortal remains excavated from ancient graves and the material goods that have been interred with them. Two recently published papers illustrate this point rather well. I’ll begin with a story about the ‘Black Death’ in 14th century England.

During the ‘Black Death’ epidemic of the mid 1300s a third of the entire human race died during a span of less than ten years. (Credit: Cosmos Magazine)

Entering Europe through Sicily in October of 1347 the bubonic plague sweep across the continent, reaching the British Islands in August of 1348. In cities like London the disease was so deadly that people died by the thousands leading to an almost complete breakdown of social norms. So many died that the time honoured customs of Christian burial were abandoned and the plague’s victims simply thrown into mass graves, several of which have been discovered and excavated by archaeologists.

A mass grave in Toulouse France dated to the time of the bubonic plague. (Credit: Science)

In rural areas however the death toll was somewhat lower, enough so that some of the usual customs for honouring the dead continued to be carried out. To date only one mass grave associated with the plague has been discovered in the English countryside and a recent study published in the journal Antiquity gives evidence that even in these troubled times the country folk still did what they could to show respect for their dead.

The mass grave was discovered in 2012 on the grounds of Thornton Abbey and contains the remains of 48 men, women and children of all ages. The location of the grave itself is curious because the local church, and its graveyard, is less than two kilometers away, so why weren’t the plague victims buried there? The researchers, led by Hugh Willmott of the University of Sheffield, speculate that perhaps the local priest and gravediggers had succumbed to the plague themselves so that the local people were forced to turn to the Abby’s monks for help.

Thornton Abbey may still look impressive from the front but there’s actually no building left behind the front gate you see here! (Credit:English Heritage)

DNA analysis of samples taken from the molars of 16 individuals showed the presence of the bacteria Yersinia pestis, the germ that causes the bubonic plague. This leaves no doubt that the people buried in the mass grave died of the plague and were therefore highly infectious. Despite the danger however the dead bodies were not simply thrown into a hole in the ground. Rather each body was laid separately in a single layer of eight rows with no overlapping. There were even indications that each body had been covered in a shroud that had since decayed. The treatment of the dead shown at Thornton Abby is further evidence that even while it seemed that the world was collapsing around them people still did what they could to honour the memory of their departed loved ones.

Layout of the mass grave found at Thornton Abbey showing that at least some care was given to the dead. (Credit: Arizona Daily Star)
Here’s the cause of all the trouble, the bacteria Yersina pestis. (Credit: Creative Biolabs)
The Mass grave at Thornton Abbey shows definite signs of greater care being given to the plague victims. (Credit: Smithsonian Magazine)

Which brings up the question of just when did human beings first begin to perform burial rituals for their dead? And could it possibly have been before our species Homo sapiens ever existed? Turns out that there is growing evidence that Neanderthals also had burial rites that, if more primitive, nevertheless still seem very human.

The first such evidence came from excavations in a site in Iraqi Kurdistan known as Shanidar Cave. In the late 1950s and early 60s fragmentary remains of 10 Neanderthal skeletons were discovered in the cave. The big news however was the discovery of clumps of pollen adjacent to one skeleton that the researchers speculated could be the decayed remains of flowers that had been deliberately buried with the dead Neanderthals, a clear sign of some kind of funeral rite.

Shanidar Cave in northern Iraq. (Credit: Science)
Layout of the original flower grave at Shanidar. Samples 313 and 314 contained the pollen grains thought to come from flowers left with the deceased. (Credit: Wonderful Things)

At the time that interpretation was very controversial. Critics counter argued that the pollen deposit was accidental, perhaps dropped by some animal. Neanderthals, it was thought, had little or no culture. After all cave paintings were made by Stone Age Homo sapiens, not Neanderthals. The earliest known examples of jewelry and carved figurines were again made by early H sapiens. Neanderthals may have had some stone tools and weapons but their societies were hardly more advanced than a troop of Chimpanzees.

Over the last several decades however evidence has mounted that Neanderthals did in fact have some culture, and even something resembling art. Cave markings have been found that are far too old to have made by H sapiens. Seashells and semi-precious stones have been discovered in connection with Neanderthal habitats that indicate they were used as decorations. Neanderthals it seemed were not as brutish as we’d assumed.

(Of course it’s worth noting at this point that the work of anthropologists like Jane Goodall over the last 50 years have shown that Chimpanzees also have a degree of what can only be described as culture, see my posts of 18Oct2017, 21Mar2018, and 16Mar2019.)

With the growing evidence supporting the funeral ritual interpretation of the burials found in Shanidar Cave you’re think that anthropologists would have returned to the cave in order to see if any further evidence could be found there. Trouble was that for about the last thirty years northern Iraq hasn’t been the safest place to do scientific research. After the recent defeat of the terrorist group ISIS however an archaeological team from Cambridge University returned to Shanidar in 2018 to reexamine the gravesite with the newest instruments and techniques.

Many regions of importance to both Archaeology and Paleontology are inaccessible to science because of the endless wars being fought there. (Credit: Chatham House)

What the team unearthed were the skeletal remains of the upper body of a Neanderthal male, including the skull. The remains, which have been dated to 70,000 years ago, were lying on the person’s back with the left arm curled up so that the hand lay under the skull. Such a position indicates that the body had been deliberately arranged rather than simply thrown into a hole. There were also signs that the grave site for all of the bodies had been deliberately dug and it is possible that a large stone placed near the skull may have been intended as a headstone or marker or a sort.

These latest discoveries raise the possibility that the Neanderthals were using Shanidar as a graveyard, a special place for the burial of the dead. According to Emma Pomeroy, an archaeologist with the team. “If Neanderthals were using Shanidar cave as a site of memory for the repeated interment of their dead, it would suggest cultural complexity of a high order.”

Evidence is growing that Neanderthals practiced burial rites that would seem to us as quite human. (Credit: Bones Don’t Lie)

The way humans care for, respect and remember their dead is one of the things that most makes us different from our animal relatives. This means that in a sense the dead can indeed speak, telling us much about what it is to be human.

Book review: The Death of Expertise By Tom Nichols.

In today’s troubled world it sometimes seems as if the truth itself were under attack. Everyday in the news we see partisan opinions being treated as established fact, we see actual evidence being spin doctored until it feels like up is down and the Sun rises in the west. On top of that there are the outright lies, the doctored videos, the conspiracy theories. It’s no wonder therefore that many average, reasonable people are finding to difficult to distinguish reality from fiction, right from wrong.

Is this the new reality??? (Credit: Cartoonstock.com)

The reason for this war on truth isn’t hard to understand. There have always been people who make money by lying, who profit by hoodwinking others, who rise to power through deceit and deception. And if you’re going base your career path on spreading falsehoods then your enemies are going to be those people who speak the truth, who rely on facts to make rational judgments, in other words experts.

The way that experts are currently under assault in our society is the theme of ‘The Death of Expertise’ by Tom Nichols. By any definition of the word Doctor Nichols is an expert, his credentials include Professor of National Security Affairs at the U.S. Naval War College and Adjunct Professor at the Harvard Extension School while also serving as an aide on national security issues to the United States Senate. Doctor Nichols knows firsthand about the campaign against established knowledge, he has experienced pushback on his expert opinion from students, laypersons and even experts in other fields.

Cover for ‘The Death of Expertise’ by Tom Nichols (Credit: Amazon)
Professor Tom Nichols, author of ‘The Death of Expertise’. (Credit: Harvard Magazine)

Doctor Nichols begins by trying to define what he means by expert and layperson, taking the time to look at both terms broadly and narrowly. By expert Nichols broadly means anyone who has received training in a ‘certain subject’ and has acquired a reasonable amount of experience in applying that training. On the other hand Doctor Nichols defines the term ‘Certain Subject’ very narrowly. For example he is an expert on security risks to our nation, he quite aware that he is not an expert on economics, or health insurance or infrastructure. In fact there are several times in his book where Nichols criticizes experts in one field who ‘go out of their lanes’ to pontificate about subjects on which they are as ill informed as any layman.

All too often today we’re led to think that gathering a large number of different opinions, no matter how ill-informed, will led us to the truth. In reality it only starts fights! (Credit: CNN)

A layperson therefore would be anyone without a deep background ‘on the subject being discussed at the moment’! And since no one can know everything we are all laypersons on some, let’s be honest many subjects. This is a fact of life, on some subjects we may be experts but most of the time we are laymen. Many of us however find it difficult to accept this situation, preferring to demand respect for our own opinion no matter how ill informed it may be.

As Doctor Nichols points out, this has been the situation for hundreds if not thousands of years. Nobody likes to feel that they are being talked down to, and we’re never quite sure whether or not we should trust someone who advertises themselves as an expert, a skepticism that is actually quite healthy. Over the last several decades however the problem of anti-intellectualism has grown to unprecedented proportions, becoming a serious problem in the way we run our society. No longer do we question those who claim intellectual authority, we attack them.

Nothing more to say! (Credit: Imgur)

After setting his boundary conditions Doctor Nichols then proceeds to detail the growth of, and the effect of this anti-expert feeling across a broad spectrum of our society. Everything is covered from the debasement of higher education into a consumer product, to the replacement of the serious study of a subject with ‘googling it’ to the rapid spread on the Internet of outright falsehoods and conspiracies. Using both individual cases and broad studies as illustrations Nichols succeeds in painting a dark picture of the dysfunction that is taking hold of western civilization.

O’k it hasn’t gotten this bad, YET! (Credit: Imgur)

That’s my biggest problem with ‘The Death of Expertise’. Doctor Nichols convinces you of the enormity of the problem and then honestly admits that he has few solutions. I suppose that isn’t a so much a criticism of the book as a feeling of hopelessness. As I was reading ‘The Death of Expertise’ I was constantly reminded of a quote from the German poet Schiller, “Against Stupidity the Gods themselves contend in vain!” I hope that isn’t the future of our democratic society.

In the end we can only hope, as Doctor Nichols does, that those people who recognize the problem, those people who value knowledge and ability will stand against the rising tide of ignorance and work to bring back a respect and reliance upon expertise. That expert and layman will find enough common ground that they can work together for the common good.

‘The Death of Expertise’ is a very important book. I heartily recommend it, but it’s certainly not a pleasant book.

More bad news about Climate Change: Antarctica’s ‘Doomsday’ glacier is melting at an accelerated rate while Arctic Ocean currents are being altered by melting ice.

2019 has now been officially recorded as the second hottest year since accurate records began over one hundred years ago. Only the year 2016 was hotter and in fact the last five years have been the five hottest ever measured. By now anyone who doubts that the CO2 that we are dumping into the atmosphere is raising the very temperature of the Earth is simply lying to themselves. The only questions left are how much damage is climate change going to cause, and how soon? Now new data is coming in from ongoing scientific studies at both of our planet’s poles that may give us some answers to those questions. Answers that we’re not going to like.

Global temperature map for 2019. A lot of red (hot) and very little blue (cool). I know I used this image in my past post but it’s worth seeing again!(Credit: Climate Central)

Thwaites glacier is considered to be the most threatened; perhaps threatening would be a better word, glacier in the entire world. Part of this is because at some 180,000 square kilometers in area it’s one of the world’s largest glaciers. More importantly however the glacier’s position along the very edge of the west Antarctic ice sheet puts it in direct contact with ocean waters that are causing it to melt at a very high rate. In fact it is calculated that the melting of the Thwaites glacier is currently responsible for about 4% of the entire sea level rise caused by global warming.

Because of its size and position adjacent to the ocean, Thwaites glacier is considered the ‘Doomsday’ glacier. (Credit: GWPF)

In order to better understand the threat posed by the Thwaites glacier a research team led by scientists at New York University’s Center for Global Sea Level Change and Environmental Fluid Dynamics Labouratory have traveled out onto the glacier itself in order to drill down two kilometers through the ice and see what is going on beneath the glacier.

Enduring the bitter Antarctic cold scientists drill through the Thwaites Glacier to understand the threat caused by global warming. (Credit: EarthSky)

What the researchers found was alarming. Along the glacier’s edge the Ocean’s comparatively warm waters, about 2ºC, are under cutting Thwaites, exposing even more of the glacial ice to the melting effect of the ocean’s heat. This undercutting will undoubtedly increase the speed of the ice’s melting and could even lead to a collapse of the entire glacier.

Warm ocean water has undercut Thwaites Glacier, exposing more of the ice and destabilizing its structure. (Credit: Daily Mail)

If a collapse does happen that could cause a rise in the ocean level by half a meter and threaten coastlines around the world. And remember, Thwaites is only one glacier, how many more are going to melt before we finally recognize the problems we are causing.

Another little sign of how Antarctica is changing because of global warming came in a small news item on the 6th of February, as an all time high temperature was recorded for the entire continent. The measurement was made at an Argentine research base called Esperanza, which sits on the Antarctic peninsula jutting up toward South America. The meteorological station at the base there recorded a high temperature of 18.3ºC, replacing the previous record of 17.5ºC set back in 2015. Although this is only the temperature of a single day it is yet one more sign of ever rising heat at the place where arguably it matters most.

Esperanza station in the Antarctic, site of the recent record warm temperature. (Credit: TreeHugger
O’k so 18 degrees C isn’t exactly sunbathing weather but for Antarctica it’s really hot! (Credit: Science Alert)

So if the Thwaites glacier, along with thousands of other ice reservoirs is melting, what is happening to all of the water that’s flowing into the world’s oceans? A team of researchers at the other end of the Earth, literally, is investigating that very question and what they’re discovering is that the oceans aren’t just slowly, quietly rising. Scientists with the ‘Impact of Climate on Ecosystems and Chemistry of the Artic Pacific Environment’ or ICESCAPE mission funded by NASA have been carrying out shipborne examinations in the Beaufort and Chukchi seas around the Artic Ocean.

When ICESCAPES measurements are combined with the data obtained from Earth observing satellites what the scientists have found is that the melted water from the northern ice sheets is increasing the flow velocity and turbulence of an oceanic current in the Artic.  This ocean current, known as the Beaufort Gyre, is a circular stream of water that flows around the Artic in a clockwise direction north of Canada and Alaska.

Ocean Current in the Chukchi and Beaufort Seas. (Credit: ResearchGate)

What the scientists discovered is that since the 1990s some 8,000 cubic kilometers of fresh water have melted into the Beaufort Gyre, while at the same time the shrinking of the ice cap has left the ocean current more exposed to the wind. This combination of increased water input and amplified wind driving it has resulted in an increase in the flow rate of and turbulence in the current. This is globally important because the Beaufort connects to the Atlantic Ocean, slowly releasing its fresh meltwater into that ocean. If the Beaufort were to release all of its accumulated fresh water into the Atlantic suddenly it could cause massive disruptions to the environment, everything from poisoning salt-water fish to affecting the path of the Gulf Steam.

Over the last 40 years the amount of ice in the Arctic has halved! (Credit: Virginia Institute of Marine Studies)

Over the last three decades the measured temperature rise in the world’s polar regions has been twice as great as those seen elsewhere on the planet. The Artic and Antarctic are the front lines of global warming, and the reports we’ve been getting from those fronts haven’t been full of good news.

Ocean Acidification, the other big problem being caused by all of the fossil fuels emissions we are dumping into the environment.

We all know the basic facts about Global Warming. We all know that the massive amounts of carbon dioxide and methane that we are releasing into our atmosphere in the form of fossil fuel emissions are acting as a sort of blanket, keeping our planet from radiating away some of the energy it absorbs from the Sun. That’s why 2019 was the second warmest year ever recorded, only surpassed by 2016. And that’s why the last five years have been the five hottest years ever recorded! And now last month, January 2020 has been declared the hottest January on record! Temperature rise is a fact and we are causing it!

Global temperature map for 2019. A lot of red (hot) and very little blue (cool). (Credit: Climate Central)

It turns out however that raising the world’s temperature isn’t the only way all of that carbon dioxide is damaging our planet. You see much of that carbon dioxide ends up getting absorbed into the Earth’s oceans. Estimates are as much as 35% of CO2 emissions wind up in the ocean. 

Everywhere you look you can see all of the CO2 we are pouring into the atmosphere. Does anyone really believe this isn’t affecting our planet in some way! (Credit: Fortune)

Well that’s a good thing isn’t it? At least in the ocean the CO2 won’t be contributing to Global Warming, right?

Perhaps not, but that doesn’t mean it’s harmless. In fact carbon dioxide dissolved in water forms carbonic acid and with all of the CO2 polluting our atmosphere enough is getting into the oceans to actually lower the pH of the world’s oceans. Not much, but remember most of the life on Earth lives in the oceans and those living things have evolved over millions of years to grow and survive at a pH level that is naturally slightly alkaline. Even the slightest change in pH level can make life very difficult for them.

The chemical equation for CO2 being dissolved in water to form Carbonic acid. (Credit: JamiiForums)

This is especially true of shellfish, crabs, lobsters, clams, oysters and the like, even coral itself. You see the shells of these creatures are composed of calcium carbonate, which dissolves in acids. Now the oceans aren’t becoming acidic enough to actually dissolve the shells of shellfish, not yet at least. What it is doing however is making it harder for those animals to grow their shells. This is especially true for the larval stages of shellfish.

Consider Dungeness crabs, one of my favourite foods, for example. Studies conducted by the Southern California Coastal Water Research Project and funded by the National Oceanographic and Atmospheric Administration (NOAA) have found that Dungeness crab larva off of the coasts of Oregon, Washington and British Columbia are having damage caused to their shells by ocean acidification from the moment they hatch from their eggs.

Dungeness crab may not look so tasty, but they sure are! (Credit: SFist)
The effect of oceanic acid on the development of the shells of Dungeness crab is greatest during their early growth. (Credit: Associated Press)

Even if those larva survive this damage to their shells will effect the crabs throughout their lives, making it harder for them to move and feed, harder to defend themselves against predators, harder to reproduce, just plain harder to live. Such added stress on a species survival can lead to a population collapse, in this case the collapse of a very valuable commercial species. Did I mention I think that Dungeness crab is delicious?

As the amount of CO2 in the atmosphere increases the amount of carbonic acid increases which lowers the pH of the oceans. (Credit: NOAA)

Other studies have revealed similar threats to other important kinds of seafood, clams, oysters and mussels. As the human race becomes ever more dependent on the oceans for food we are actually poisoning the very species that we are harvesting in ever greater numbers to feed ourselves.

Ocean acidification is a threat to many commercially valuable species of shellfish. (Credit: KCET)

So far I been discussing the potential harm to shellfish, invertebrates caused by ocean acidification, what about actual fish, vertebrates? Well there’s some bad news there as well. A new study from the Heinrich-Heine University in Duesseldorf along with the University of Duisburg-Essen in Germany has analyzed the effect of lower pH on the growth of the skin scales of the Puff Adder Shyshark that lives in the Atlantic waters off of South Africa. These scales, like the shells of invertebrates, contain calcium and therefore are becoming damaged by the increase in ocean acidification.

Enlarged view of damage to shark scales caused by ocean acidification. (Credit: EurekAlert)

However even if fish are not directly harmed by the effects of ocean acidification they certainly will not avoid indirect damage from the loss of coral reefs. After all coral is calcium carbonate and large sections of coral reefs have already been observed to have been ‘bleached’, a loss of colour which indicates poor health.  Further acidification, along with temperature rise, could lead to the loss of huge parts of the world’s coral reefs and all of the species that depend on those reefs.

He may look tough but compared to all of the harm we’re doing to the world he’s a little pussycat! (Credit: Intelligent Living)

To sum it all up, we humans now have the greatest effect on the environment of any species in Earth’s history, but most of us are not even thinking about the effect we’re having. We’re still behaving as if the all of the many different kinds of waste that we throw away is ‘out of sight, out of mind’. That is no longer true, ocean acidification, like temperature rise and plastic pollution, is only one of the ways in which we are poisoning the only planet we have.

Scientists have three new instruments which will enable them to observe the Sun in greater detail than ever before.

Our Sun plays such an important role in our very existence that the study of this single celestial object is a separate branch of astronomy unto itself. In ancient times the positions on the horizon where the Sun rose and set each day of the year were carefully plotted and recorded, as were the patterns of Solar eclipses. It is thought that some of the world’s ancient monuments, like Stonehenge and Maya temples, were used as primitive Solar observatories.

When viewed from the center of Stonehenge the Sun rises directly behind the Heel Stone on the summer solstice. (Credit: Earthsky)

The Sun was one of the first objects that Galileo turned his early telescope towards, discovering sunspots in the process. Ever since then scientists have kept an almost daily record of those dark spots on the Sun’s face. Every time a new kind of scientific instrument was invented it usually wasn’t long before that instrument would be turned on the Sun. In fact the element helium was discovered when the newly invented spectrograph was used to study the light from the Sun.

Using his newly invented telescope Galileo was the first person to observe and record sunspots. (Credit: The Galileo Project)
Spectral Lines in the light coming from the Sum allows astronomers to determine the chemical composition of the Sun. (Credit: FlatEarth Debunkers)

Now Solar astronomers have three powerful new instruments with which to probe the star at the center of our Solar System. One of these is NASA’s Parker Solar probe which I’ve written about several times now, see posts of 7June2017, 6January2018, 5September2018, 3November 2018 and 18December2019. So here I will only give a brief update to the spacecraft’s mission.

NASA’s Parker Solar Probe is already the closest man made object to the Sun but over the next few years it is going to get even closer. (Credit: University of Arizona)

After a flyby of the planet Venus back in December 2019, Parker used the tug of Venus’ gravity to put it on an orbit that sent it even closer to the Sun. The closest approach by Parker, breaking its own previous record from just last year, occurred on January 29th 2020 at a distance of only 18.6 million kilometers. That distance is only about 12% of Earth’s distance from the Sun which means that the sunlight hitting Parker was more than 60 times as strong it ever gets here on our planet.

And in order to get so close to the Sun and its gravity Parker has to be moving very fast, faster than any object ever built by mankind, again breaking its own record. The probe’s speed on the 29th hit a maximum of 393,044 km/h, fast enough to go from the Earth to the Moon in only one hour!

The scientists are still processing the data obtained by Parker on this close flyby so we will have to wait to hear if any new discoveries were made. Over the next four years Parker is scheduled to get even closer to the Sun, eventually getting as close as 6.9 million kilometers.

The Daniel K. Inouye Solar Telescope (DKIST) on the other hand isn’t going to be making any close approaches to the Sun; it’s permanently installed on the top of the Haleakalā volcano in Hawaii. However the new Solar telescope, with a main mirror of about four meters in diameter, is now giving astronomers the highest resolution, highest definition images of the Sun’s surface ever. See images below.

The Daniel K. Inouye Solar Telescope. (Credit: Maui Now)
Closest ever view of the surface of our Sun, as provided by DKIST. (Credit: Devdiscourse)

The kernel shaped objects that you see in the image are fountains or geysers of hot gas upwelling from deep beneath the surface of the Sun. Each of those geysers by the way, is about the size of the state of Texas! These initial images are already telling astronomers a great deal about how the Sun’s energy gets from it’s core where fusion occurs to the photosphere, the part of the Sun that we see.

In the next few months additional instruments are to be incorporated into DKIST that it is hoped will enable it to study the magnetic fields around sunspots, revealing some of the secrets of those mysterious objects. In any case the DKIST telescope has many more years of useful work ahead of it so at the moment we can only guess at what discoveries it will make.

And there is one more Solar instrument that will soon be adding to what we know about our home star. The European Space Agency’s Solar Orbiter has just been launched last night, the 9th of February and is beginning a 7 year mission to study the Sun. The planned orbit for the spacecraft will not take it as close to the Sun as the Parker probe however, closest approach distance for Solar Orbiter will be about 45 million kilometers. However it is planned for the probe to be placed into an orbit that will carry it 35º above the plane of the ecliptic, giving scientists their first clear, close up look at the Sun’s poles. This is important because many of our theories about the Sun’s 11 year sunspot cycle make predictions about conditions near the Sun’s poles that so far we’ve been unable to check because from our viewpoint the poles are at a very slanted angle, making it difficult to observe any of their details.

The Solar Orbiter space probe isn’t going to get as close to the Sun as Parker will, but it’s going to get our first good view of the Sun’s polar regions. (Credit: NASA)
The Launch of Solar Orbiter. The probe has a two year journey to reach its proper orbit before its seven year mission. (Credit: Spaceflight Now)

Together these three instruments may inaugurate a new era in the study of our Sun. Over the next decade the wonders that could be discovered…well I guess we’ll just have to wait and see won’t we. 

Two new Neutrino experiments enable Physicists to measure the heat being generated in the Earth’s core and may have discovered a new particle and new physics beyond the Standard Model.

I’ve written about neutrinos several times now in this blog. (See posts of 30July2017, 2December 2017 and 6June2018.) Neutrinos are known as ghost elementary particles because they interact so rarely, so weakly with other particles. In fact, although billions of neutrinos are passing through your body every second you’ll be lucky if a single neutrino interacts with you during your entire life.

Fusion reaction that powers the Sun. Two neutrinos are released in the process, the particles shown as white balls.. (Credit: Quora)

Most of those neutrinos come from the fusion processes that produce the energy of our Sun but there are also anti-neutrinos whizzing about that mostly come from the decay of radioactive elements in the ground along with the fission reactions in nuclear reactors. I’ve often considered it amusing that fusion, which takes lighter elements and combines them into heavier elements, produces a lot of neutrinos while fission and nuclear decay, which break down heavy elements, produce mainly anti-neutrinos.

Beta decay of the Carbon 14 nucleus produces a Nitrogen nucleus while emitting an electron and an anti-neutrino. (Credit: Radiation Dosimetry)

For almost fifty years now scientists have been using neutrinos in order to study our Sun, and learned a great deal about neutrinos in the process. Neutrino detectors consist of large containers of water that capture the neutrinos while photomultiplier tubes that line the inner walls of the container detect the faint light produced by those captures. The detectors themselves are buried deep within mine shafts in order to minimize the interference caused by cosmic rays. These ‘neutrino telescopes’ detect no more than a handful of neutrinos a day but those few particles have lead to many important discoveries.

The walls of neutrino telescopes are covered with photomultiplier tubes that collect the light emitted by neutrino captures. (Credit: Sci-news.com)

Now another neutrino observatory is using anti-neutrinos, known as geoneutrinos to study the interior of the Earth. The Borexino detector, located at the Laboratori Nazionali del Gran Sasso in Italy and containing some 1000 metric tons of water has been in operation now since 2007. Buried 1400 meters beneath the Earth’s surface in the Gran Sasso massif near Rome, Borexino has succeeded in capturing 53 geoneutrino events. (It’s worth noting that during that time the detector was also capturing Solar neutrinos.)

The design of the Borexino neutrino telescope. (Credit: ScienceDirect.com)

And those 53 anti-neutrinos were enough to allow the theoreticians to answer a question that has long perplexed geologists and geophysicists, how much of the Earth’s internal heat is being generated by the decay of radioactive elements? Thanks to the data provided by Borexino we now know, with an 85% confidence level, that just about half of the heat in our planet’s core comes from nuclear decay. In fact the data obtained by Borexino has even allowed physicists to estimate the amounts of the radioactive elements Uranium and Thorium remaining inside the Earth.

Thanks to Borexino we now have actually measured the amount of heat being generated in Earth’s core by radioactive decay! (Credit: NBC News)

Borexino will continue to capture geoneutrinos, and each new detection will increase the accuracy of the results. There are also plans to build a larger detector at Gran Sasso so in the years to come geoneutrinos may tell us even more about the makeup of the interior of the Earth.

Now if you think that calculating the energy generated in the Earth’s core based on just 53 detections of elementary particles is pretty amazing well there are a group of physicists attached to the Antarctic Impulsive Transient Antenna (ANITA) experiment in Antarctica who think that the detection of three particles could overturn the standard model of particle physics.

ANITA is a completely different sort of neutrino detector than Borexino, but one that is only sensitive to the very highest energy neutrinos, those with energies far greater than that of neutrinos coming from either the Earth or Sun. ANITA is intended to study the neutrinos associated with high-energy cosmic rays from quasars or black holes or supernovas.

The way ANITA detects these high-energy neutrinos is that while in space the neutrinos are moving at almost, but not quite the speed of light in a vacuum as they pass through the Antarctic ice they are actually moving faster than the speed of light in ice! Such particles will give off a kind of radiation known as Askaryan radiation until their speed is reduced below that of light, or they leave the ice. The radiation that these high-energy neutrinos give off happens to be in the microwave region of the electro-magnetic spectrum, a type of radiation that we humans are very good at detecting. Your cellphones operate in the microwave region for example.

The ANITA detectors are lifted into the stratosphere by a helium balloon. (Credit: The Scientific Community on Antarctic Research)
The ANITA Experiment catches EM waves giving off by ultra-high energy neutrinos as they skim through the Antarctic ice sheet. (Credit: ResearchGate)

Funded by NASA, the ANITA experiment therefore consists of an array of 40 microwave antennas that are lifted into the stratosphere over the Antarctic by a helium balloon in order to maximize their coverage area. Operating on an every other year basis ANITA has now flown four times and detected numerous signals associated with high-energy neutrinos that have taught physicists a great deal about the neutrino component of Ultra High Energy Cosmic Rays (UHECR).

Launch of the ANITA Experiment. The detector will remain aloft for about four months during the Antarctic summer. (Credit: Jeff Filippini)

Three of those detections however seem to come directly up from beneath the detector, as if they’ve come through the entire Earth, something high-energy neutrinos should not be able to do. Remember the whole time that they’re passing through solid material the neutrinos are giving off Askaryan radiation.

So if these three particles weren’t the sort of neutrinos that physicists are familiar with, what were they? Some new form of neutrino? Or an entirely new type of particle beyond the Standard Model? Three detections do not give enough evidence for a definitive answer but ANITA is only one of a number of experiments that are giving indications of physics beyond the Standard Model.

Further flights with ANITA are planned, as are other experiments designed to give a clearer picture of what these strange particles might be. Physicists have never been happy with the Standard Model, which fails to answer as many questions as it does answer. How long it will take to understand what is beyond the Standard Model, and what experiment will finally succeed in making the breakthrough is anybodies guess. You can be certain however that physicists will keep on looking until they find those answers.

Magnetic Resonance Imaging (MRI), what is it like to have one, how do the work and what do they do?

MRIs (Magnetic Resonance Images) are becoming an increasingly common tool used by doctors to aid them in diagnosing the medical condition of their patients. I’ve just had my third MRI taken this morning so I thought this would be a good opportunity to talk about how MRIs work and why they are such useful tools for doctors.

Patient being prepared for an MRI. (Credit: Northwest Radiology)

For those who have never received an MRI I’ll start with a short description of the experience. First and foremost, no metal of any kind can be placed within or even near an MRI machine. MRI machines produce intense magnetic fields, so intense that magnetic materials like iron can be hurled across the room while even non-magnetic metals like copper or aluminum can be inductively heated to dangerous temperatures. Patients being examined must remove all wristwatches, rings etc. while people with metal implants in their bodies, say a steel rod to strengthen a broken bone, simply cannot have an MRI because it would be extremely dangerous for them.

The magnetic field at the center of an MRI machine can be 30,000 times as powerful as Earth’s magnetic field. (Credit: Magnetic Resonance Imaging)

There are two basic designs of MRI machines, open and closed. Closed are the original and still more common type, if only because they cost less. A closed MRI machine consists of a doughnut shaped solenoid, barely large enough to fit a slab that a person can lay on through the doughnut hole. The portion of the patient’s body being examined is kept motionless in the center of the doughnut solenoid, which produces the intense magnetic fields required for the resonance imaging.

Because the opening of the doughnut in a closed MRI machine is so small many people get a strong feeling of claustrophobia while being examined. So open MRI machines were developed with larger, more open volumes of intense magnetic field. Of course, since generating a intense magnetic is costly; generating a larger volume of intense magnetic field is even more expensive. Therefore open MRIs are less common than the smaller, less costly closed version.

Typical Open MRI machine. The extra space can make patients feel better but costs a fair penny! (Credit: Medical Imaging)

MRIs are also very noisy. If you’ve ever walked past an electric power sub-station you will have heard the 60 hertz hum of the transformers, a sound I know all too well. That sound is caused by the alternating current flowing around the magnetic core of the transformers literally causing them to vibrate. Well the magnetic fields generated during an MRI exam are even stronger, turn on and off frequently and consist of many different frequencies. All that causes the MRI machine to bleep and chirp and buzz at very loud volumes, and remember the patient is stuck right in the middle of the noise. Most states, perhaps all of them by now, require MRI patients to wear ear protection in order to prevent any damage to their hearing from the noise.

So much for the experience of having an MRI. How do MRIs work and what makes them different from say, having an X-ray taken?

Nuclear Magnetic Resonance (NMR) is a purely quantum mechanical phenomena dealing with those atoms whose nuclei possess an odd number of either protons or neutrons. Such nuclei have a sum magnetic moment of one Bohr magnetron to them and when placed into a strong external magnetic field they will align that magnetic moment with the external field. (Actually each proton and neutron have their own magnetic moment but in a stable nucleus the protons and neutrons arrange themselves so the entire nucleus has a total magnetic moment of no more than one.)

Now if a second, oscillating magnetic field is applied perpendicular to the stable field at just the right, resonant frequency the nucleus will begin to precess like a top that is losing its spin. That resonate frequency is determined by the properties of the nuclei and the strength of the stable magnetic field. That precession then causes the nucleus to radiate electro-magnetic waves in the 60-1000 million Hertz range (MHz), almost the same frequencies as broadcast television. Frequencies that radio engineers know very well how to detect and measure.

Nuclear Magnetic Resonance is caused by the precession of the nucleus of an atom. (Credit: www.jeol.co.jp)

By observing those EM waves physicists have been able to learn a great deal about the internal structure of many different nuclei with devices known as Nuclear Magnetic Resonance Spectrographs. As far as medical diagnostics is concerned however only the simple nucleus of a hydrogen atom, just a single proton, is used. You see with all of the water in our bodies, and every molecule of water having two hydrogen atoms medical MRI machines can scan our entire bodies using only hydrogen. This concentration on a single type of nucleus helps make a very expensive machine a little bit less costly.

A Nuclear Magnetic resonance Spectrograph is an instrument that physicists use to study the nuclei of various atoms. (Credit: www.the-scientist.com)

This is how an MRI machine can see inside our bodies, measuring the variations in the moisture level of our different organs by the intensity of EM radiation given off by the hydrogen nuclei in that organ. That is what makes MRIs more sensitive to things like tumors, lesions, tears and other abnormalities than X-rays. That is why more and more doctors are prescribing MRI examinations in order to help diagnose their patients medical problems, despite their high cost.

When I tore the rotator cuff in my right shoulder the Doctor diagnosed the condition using MRI. (Credit: Centeno-Schultz Clinic)
An MRI of a human brain. Images like this are teaching us so much about how the human body works. (Credit: kxci.org)

 Over the last century we humans have been developing ever more powerful and sensitive drugs, treatments and instruments for dealing with our diseases and other aliments. MRI is one of the more remarkable of those developments, allowing doctors to see inside the human body with a clarity never before possible.

Building things from living tissue. Two scientific projects highlight the advances being made in using life as a construction material.

It’s built into the language that we use, we build with non-living materials and we grow living things. Those time-honoured definitions are starting to get a little blurry however as scientists and engineers develop ever more complicated and sophisticated machines that behave almost like living things. Meanwhile there are biologists and biochemists who are working to develop techniques by which we can build things with living tissue. In this post I’m going to talk about two projects that are making considerable progress in the latter category.

As Children we quickly learn the difference between living and non-living things. Thanks to scientists today that difference is steadily shrinking. (Credit: Pinterest)

The first group, working at the University of Colorado Boulder’s Department of Civil, Environmental and Architectural Engineering, has literally discovered a method to construct a living brick, as in a brick for building your house. The bricks are manufactured by incorporating the bacteria Synechococcus cyanobacteria into a solution of sand, gelatin and a bit of water. As the bacteria metabolize the gelatin, absorbing CO2 from that air in the process, it becomes the mineral calcium carbonate, a cement that holds the sand together as in concrete.

Living bricks growing at the lab at the University of Colorado. (Credit: C4ISRNET)

These ‘living bricks’ have several advantages over the bricks that humans have made for thousands of years. As I’ve already mentioned the bacteria absorb CO2 from the air in order to convert the gelatin into cement, and in today’s world getting rid of some CO2 is definitely a good thing.

The life cycle of living bricks! (Credit: SlashGear)

However the main advantages of the living brick are twofold. First of all instead of manufacturing the bricks one at a time since they use a bacteria to bind them together you can actually grow them. So long as you have a starter brick you can produce as many bricks as you need just by adding sand and gelatin, almost like having a starter yeast in bread making. The second advantage is that when damaged, say a crack forms in the brick for some reason; the living bricks can actually repair themselves to a degree, just like a cut on your arm healing.

There are still several problems remain to be overcome, for one the gelatin is made from animal collagen and is fairly expensive in large quantities. Nevertheless it is hoped that the living brick could soon be useful in construction projects in remote locations, like perhaps Mars!

The second development project is even more ambitious, attempting to create a ‘living robot’ from stem cells, those cells in the body that have yet to be turned into muscle cells or stomach cells or brain cells. The team of scientists from the University of Vermont, Tufts University in Maine and Harvard University used the stem cells in frogs to fabricate a small living creature made up of several hundred cells living cells. The actual species of frog whose stem cells were used was the African clawed frog, Xenopus laevis and the tiny machines made from their stem cells are called xenobots. The xenobot’s outside was made of skin cells to give it shape while inside were heart muscle cells to enable it to move.

The African clawed frog, Xenopus Iaevis. Stem cells from this critter were used to manufacture the first living machine. (Credit: Wikipedia)
Introducing the Xenobot, a robot ‘manufactured from living cells. (Credit: MIT Technology Review)

But something that simply moves isn’t a robot, robots are specifically designed to execute instructions, to perform a task and the researchers have actually succeeded in ‘evolving’ their creatures to carry out simple commands. They did this by employing a computer algorithm that ‘reproduced’ inside the algorithm those xenobots that came closer to behaving in a desired manner while eliminating from the program those that did not.

A computer algorithm was used to determine where to put skin cells (green) and where to put muscle cells (red) in order to make the xenobots perform desired functions. (University of Vermont)

After several generations the researchers had developed an entirely new form of living creature that would carry out simple tasks. The researchers hope that in time xenobots could be used to help remove toxic or even radioactive material from spills, collecting microplastic particles and perhaps even removing plaque from inside our arteries or delivering drugs to areas inside the bodies.

One day perhaps xenobots will be employed in our bloodstreams to deliver drugs or even remove blockages! (Credit: European Pharmaceutical Review)

There’s a lot of work still to be done but xenobots are something entirely new, neither machine nor living creature they are a new kind of tool for us to use. Who knows what kind of jobs they’ll enable us to do one day?