Science – Page 33 – Scienceandsf -A Blog Published by Robert A. Lawler

Lasers, what are they and how do they work?

Earlier this year I celebrated the fiftieth anniversary of the Moon landing of Apollo 11 by publishing a series of eight articles about the ‘Space Race’ of the 1960s. I enjoyed that task so much that I decided to write a few more posts about some of the other cool technologies that made the news during that decade; I hope you’ve been enjoying them.

In this post I’ll be talking about lasers, those intense beams of light that can not only cut through steel but also read the data off of DVDs, print our documents, are used to measure distances with extreme accuracy and are even used in medical surgery, especially eye surgery. Most people know that the word LASER is an acronym standing for ‘Light Amplification through Simulated Emission of Radiation’ and many have heard that the property that makes a laser beam different is something called ‘coherence’.

In the 1960s Lasers were devilish weapons the bad guys used to threaten James Bond! (Credit: Pinterest)

This coherence actually comes in two forms, spatial and temporal. In spatial coherence the photons, the particles of light are emitted in very precisely the same direction resulting in the very narrow beam that lasers are best known for. Temporal coherence means that those photons all have very precisely the same frequency. It also allows laser pulses to be very accurately timed, On and Off along with the amount of time a pulse lasts.

The property that makes a laser beam different from ordinary light is called Coherence. (Credit: Sciencewise.info)

The phenomenon that produces Laser light is a purely quantum mechanical effect that was first recognized by Albert Einstein in 1917. Einstein was working on the problem of how an atom with its electrons in the minimum energy or ‘ground state’ can be excited into higher energy state by absorbing a photon of just the right energy. At the same time an atom that is in an excited state can also decay back into its ground state by emitting a photon with the exact same energy.

Einstein was calculating the probabilities of a Atom absorbing or emitting a photon when he discovered the possibility of Stimulated Emission. (Credit: Sciencewise.info)

As he calculated the probability per unit time of that decay process occurring Einstein also noticed that the probability increased a lot if another photon of just the right energy happened to be near the excited atom. The photon stimulated the decay of the atom and the emission of a second photon identical to the first!

For the next several decades simulated emission remained nothing more than an interesting possibility. It wasn’t until 1928 that Rudolf W. Ladenberg even confirmed its existence but the idea of a practical usage of the phenomenon seemed almost impossible. That would require a material that had the majority of its atoms in the excited state, at condition called a population inversion and which was thought to never occur in nature.

It wasn’t until 1951 that Joseph Weber suggested that a microwave cavity could be used to produce a population inversion, by confining the atoms and pumping in energy the atoms could be ‘supercharged’. A small microwave signal could then simulate all of the excited atoms to decay greatly amplifying that small initial signal. The device was first build two years later and called a Maser for Microwave Amplification through Simulated Emission of Radiation. Masers are still used today by radio astronomers to amplify the extremely weak signals they study.

Charles Townes and the first MASER, a radio version of a laser that was actually invented first! (Credit: IEEE Spectrum)

With the Maser showing how it could be done the hunt was on for a material that could create a population inversion at optical wavelengths. As often happens nowadays there were several teams of researchers who came close, Bell Labs and Columbia University among others. It was Theodore H. Maiman at Hughes Research Laboratories who produced the first laser by employing a synthetic ruby crystal pumped by a flashlamp to produce a pulse of red laser light at a wavelength of 694 nanometers.

Theodore Maiman holding the parts of the first Laser. (Credit: SciHi Blog)

It wasn’t long before continuous lasers were also developed using helium or neon as the lasing material. Then in 1970 Zhores Alferov in the USSR along with Izuo Hayashi and Morton Panish at Bell Labs demonstrated that semiconductor material could also be employed as a lasing material. Before long lasers were being manufactured cheaply and in mass quantities.

The workings of a semiconductor laser. (Credit: Google Sites)

Today lasers are everywhere; they are in the checkout scanners at supermarkets, our DVD and CD players and laser printers and if you get your TV signal on optical fiber it’s a laser that transmits the signal going through the fiber. Research into new types of lasers is ongoing and laser manufacturing is a big industry. The non-semiconductor laser industry is today valued at more than $2 billion dollars while semiconductor lasers total more than $3 billion.

Today Lasers are so cheap you can buy one for just a few bucks! (Credit: Thorlabs)

Lasers seemed almost magical back in the 1960s, a symbol of how far our science and technology had come in its control of nature. Today we pretty much take them for granted. That’s progress I suppose.

Are scientists on the verge of putting human beings into Suspended Animation?

Suspended Animation is defined as is an extreme slowing, or even stopping of the physiological processes of a living creature for a period of time and then fully resuscitating that creature back to its normal life. During suspended animation the heartbeat, breathing, even the metabolic processes of individual cells are slowed if not halted entirely.

Suspended Animation as imagined in Science Fiction. (Credit: Outer Places)

Also commonly known as hibernation, in nature suspended animation is used by many creatures to ‘sleep’ their way through periods of scarce resources. The classic example is of course that of bears hibernating through the winter when there is little food for them to eat but there are also creatures who suspend their life processes during times of drought or extreme heat.

Female Bears even give birth to their cubs while hibernating. (Credit: Country Life)

In science fiction suspended animation has played a key role in many SF stories, novels and movies. In those stories suspended animation allows human beings to undertake long space missions without expending the resources, food, water and air that such long voyages would otherwise require. Some of the most famous SF stories employ suspended animation for this purpose including ‘2001: A Space Odyssey’, ‘Alien’, the ‘Space Seed’ episode of the original Star Trek, I could go on and on.

Here’s the reason why space scientists are interested in Suspended Animation. (Credit: Animalsake)

In the ‘Space Seed’ episode of ‘Star Trek’ Khan and his companions escaped the 20th Century by using Suspended Animation. (Credit: Paramount)

And make no mistake NASA is keenly interested in the possibilities that suspended animation could bring to their goal of exploring space. Problem is however, unlike bears human beings don’t hibernate, even when we sleep our metabolism hardly changes from its normal rate.

Medical doctors are also very interested in the possible uses of suspended animation in treating patients suffering from traumatic injuries. Surgery is very stressful and surgeons often need to hurry through an operation so that the patient won’t die on the operating table while they are trying to save them. The ability to place the patient into suspended animation would allow surgeons to just take their time and do a more through and careful job.

Surgeons often have to rush through operations if they are to have any chance of saving a patient’s life. Suspended Animation could give them more time in which to do a better job. (Credit Getty Images)

Based upon our knowledge of other mammals that do hibernate the key to suspended animation is hypothermia or a chilling of the body’s temperature. You see our brain cells begin to die after just five minutes without oxygen and even muscle cells will start to die after an hour. If the temperature of the cells can be reduced however their oxygen requirement is also reduced and they can survive much longer.

Cooling the body temperature is a key part of suspended animation because it greatly reduces the metabolic rate. (Credit: FutureTimeline.net)

There are plenty of examples people who have actually survived cardiac arrest for long periods of time because their bodies were kept cold. Unfortunately none of these occurrences happened under labouratory conditions so they provide only anecdotal information.

In order to obtain actual measurements of how suspended animation works scientists have been forced to do experiments with animals. A 2005 study was conducted at the University of Pittsburgh’s Safar Center for Resuscitation Research. In this series of experiments dogs were placed into suspended animation by draining the blood out of their systems and replacing it with a low temperature solution. The animals were clinically dead for a period of three hours but when the blood was returned to their circulatory systems and an electric shock employed to restart their hearts the dogs were revived, most without any evidence of brain damage.

A similar experiment was carried out the next year at Massachusetts General Hospital in Boston. In this study pigs were used as the test animals. In the experiment the pigs were first anaesthetized and then given a severe injury comparable to one that a shooting or car crash victim might receive.

When half of the animal’s blood was lost it was replaced by a chilled saline solution and the pig’s body kept at a temperature of about 10ºC. While the animal was in suspended animation the injuries were repaired after which the lost blood was replaced and the pig brought back to life.

In the Boston experiment a success rate of 90% was achieved. What the researchers found most important was the way that suspended animation allowed them the time they needed to operate on the test animals.

Now for the first time this technique is being used on human beings, not chosen test subjects but the actual victims of car crashes or shootings. Emergency room surgeons at the University of Maryland Medical Center in Baltimore are attempting to employ suspended animation to prolong the life of car crash or shooting victims who have gone into cardiac arrest and whose chance of survival is only 5% due to the severity of their wounds.

Emergency room patients whose injuries are severe and who have gone into cardiac arrest generally have less than a 5% chance of surviving. (Credit: Wikipedia)

As in the earlier animal studies the victim’s blood is replaced with a chilled saline solution and the body’s temperature is brought down to around 10ºC. The surgeons then have two hours to repair the victim’s injuries before the blood is replaced, their body warmed up and the heart restarted.

The plan is for a trial of the technique with 10 people, the results will then be compared to those for 10 people who have been treated with standard emergency room procedures. The final comparison will then be published, hopefully early next year.

Now the purpose of this study is not to develop suspended animation as a means of enabling humans to explore the Solar System. As lead surgeon Samuel Tisherman wants everyone to know, “We’re not trying to send people off to Saturn. We’re just trying to buy ourselves more time to save lives.”

Nevertheless you can bet that NASA is paying attention to the study. If suspended animation works in the operating room there will be further experiments designed to increase the time that a human being can be kept in hibernation. Suspended animation would be a real game changer in human exploration of space, the question is, how long will it be before we are ready to employ it?

Space News for November 2019.

Some good news coming this month from space, successes with both manned and unmanned programs along with an interesting new concept for a future space probe. Let’s get started.

First up I’d like to talk about Japan’s Hayabusa 2 space probe that has been studying the asteroid Ryugu, see my posts of 6 January 2018, 30 June 2018, 20 April 2019 and 3 June 2019. Since arriving at the asteroid back in mid 2018 Hayabusa has photographed the asteroid, send down two landers to its surface and even fired a bullet and cannonball at it in order to blast holes that would reveal the asteroid’s internal material. Hayabusa then touched down briefly on Ryugu in order to collect some material from one of the blasted holes.

The asteroid Ryugu that was visited by Japan’s Hayabusa2 space probe. The arrow marks the spot at which Hayabusa fired its projectile. (Credit: Universe Today)

Artists impression of Hayabusa2 collecting samples of Ryugu from the crater its projectile made. (Credit: Universe Today)

Now Hayabusa has left Ryugu and is on its way back to Earth. In late 2020 the spacecraft will release a canister containing the samples collected from Ryugu that will hopefully enter the atmosphere and touch down in the outback of Australia. Once recovered the material from the asteroid will be studied to reveal some of the secrets of how our Solar System was born.

As for the Hayabusa 2 probe itself, well it will pass by our planet and make an escape maneuver that will send it back out into the Solar System where it may continue to send back data for years to come. Let’s all wish it well.

Another recent event was the successful completion of a pad abort test by Space X’s crewed version of their Dragon capsule. This test is designed to verify the capsule’s ability to quickly yank the astronauts away from the launch pad in the event of a potentially deadly problem with the booster rocket.

The Space X crew Dragon capsule undergoing its pad abort test. (Credit: CollectSpace)

You may recall that back in April a Dragon capsule spectacularly failed this very test, the solid fuel rockets intended to pull the capsule safely away instead triggering a massive fire. This failure led to months of investigation as to the cause of the ‘anomaly’ along with a major redesign of the capsule’s abort system.

The April failure of the crew Dragon in its pad abort test. (Credit: AmericaSpace)

That redesign must have done the trick because this time the abort test went off without any problems. That leaves Space X with only the in-flight abort test to pass before a manned mission to the International Space Station (ISS) can be scheduled, hopefully early next year. The competition between Space X and their rival, Boeing’s Starliner capsule is coming down to the wire, which will be the first commercial company to launch astronauts into space? I’ll let you know.

Boeing’s Starliner capsule undergoing its pad abort test. (Credit: NASA)

Meanwhile NASA is continuing its ongoing effort to design new space probes for the continued exploration of our Solar System. One place the planetary scientists are very anxious to study is Saturn’s moon Titan. Titan is the only moon in the Solar System to possess a thick atmosphere and although its surface is extremely cold it still has bodies of liquid, liquid methane that is.

In fact Titan has so many different terrains and environments that a single robotic lander of the kind that have been so successful on the Moon or Mars would only be able study one particular type of the environments of Titan. On the other hand sending multiple probes to do a comprehensive study would be far too expensive, so what can the space agency do? Be innovative!

Engineers from NASA’s Innovative Advanced Concepts (NIAC) program have teamed with both Stanford and Cornell Universities in an effort to develop a ‘shape shifting’ robot that can alter its configuration that will allow it to walk on land, or float on liquid methane or even fly through the air. The current design rolls along the ground like a drum but when required the upper half can separate itself and fly on internal propellers. See image below.

Breadboard model of a shape shifting robot space probe being evaluated by NASA (Credit: JPL-NASA)

Now the engineers do have one big advantage, Titan itself. You see the atmosphere on Titan is thicker than Earth’s even though the gravity on Titan is less than a third that on our planet. These two conditions will actually make flying easier on Titan.

On the other hand floating on a sea of oily liquid may be a little more difficult. Nevertheless the engineers are hard at work on the problem. The final design will be a modular concept, see image below, with each of its various sections being capable of independent action.

Artists impression of the completed shape shifting space probe. (Credit: JPL-NASA)

The current schedule calls for a Titan probe to be launched in 2026 with its arrival in 2034 so the engineers at NIAC still have some time to work on their designs. The concept of a shape-shifting robot is only one of the advanced ideas NASA is considering for the space probes of the future, each one more amazing than the last.

One last little item before I go. You should recall that back in January the New Horizons space craft, which had already made the first ever flyby of Pluto in July 2015, successfully made another flyby of the furthest ever object visited by a man made probe. See my posts of 3 January 2019 and 30 January 2019.

The Kuiper belt object 2014 MU69 visited by the New Horizons space probe. (Credit: NASA)

Officially known as 2014 MU69 NASA had given the Kuiper belt object the nickname of Ultima Thule, an ancient Latin name for a mythical far northern land. Now however 2014 MU69 has had that nickname taken away from it for reasons that have nothing to do with science or astronomy.

You see Ultima Thule is also the name that the Nazi gave to their fictitious homeland for the Aryan ‘Master Race’. Just to make things worse, even today there are racist, white supremacists who continue to use that name to support their hate filled rhetoric.

The new name chosen by NASA is Arrokoth, which means sky in the Native American Powhatan language. Arrokoth is certainly a good name, perfect for an object in our Solar System and if it had been the first name chosen for 2014 MU69 I would have applauded the choice. But Ultima Thule is also a good name, a name with an ancient, honourable history. To my mind this is another example of how a small group of horrible people have succeeded in perverting something wonderful into something dark and ugly.

‘Soft Robots’ inspired by living creatures are becoming the new frontier in automation.

The image we all have of robots, provided courtesy of sci-fi movies of course, is that of a hard metallic body and limbs with a basically human shape. After all humans have been using metals for a long time and of course we’re quite familiar with how to use our own body shape and limbs in order to get things done. So it’s understandable that the industrial robots that have been developed over the last few decades would resemble metal and plastic versions of our own body parts.

Robby the Robot from ‘Forbidden Planet’. (Credit: IMDB)

The reality of Robots in our world today. (Credit: Technavio)

Other creatures have other ways of doing things however and quite often their way is better than ours. Robotic engineers have started to realize the advantages that these alternate ways of moving and manipulating can provide to their designs. At the same time they are also beginning to employ different materials in the construction of their robots. Together these new technologies are known as soft robots or biohybrid robots and they’re gaining a lot of attention as they begin to accomplish tasks that other robots found to be difficult or even impossible.

Swimming is one activity that we all realize that humans aren’t really designed for, so the idea of designed a swimming robot to resemble a fish makes a lot of sense. It’s not surprising then that researchers at the University of Virginia’s School of Engineering are developing a robot based upon the anatomy of one of the ocean’s fastest and most efficient swimmers, they call it Tunabot.

Tunabot. (Credit: University of Virginia)

Led by Professor Hilary Bart-Smith Tunabot has been funded by the U. S. Navy with the goal to not only design and develop a robot that mimics the swimming behavior of a yellowfin tuna but to use that robot as a platform to better understand alternative forms of propulsion. Tunabot itself is an eyeless, tailfin only model some 25cm in length whose swimming prowess can be measured in a test tank at the Mechanical and Aerospace Engineering at UVA. With its tail beating at the same rate as a yellowfin does in the wild Tunabot is capable of producing a propulsive force nearly equivalent to that of its natural counterpart.

Tunabot in action. (Credit: Tech Xplore)

The development of Tunabot is only the start of the research program however. “We don’t assume that biology has evolved the best solution.” Professor Bart-Smith says. “Our Ultimate goal is to surpass biology. How can we build something that looks like biology but swims faster than anything you see out there in the Ocean?”

Another team of researchers at Cornell and the University of Pennsylvania are also developing a robotic fish as their test platform for a radical new technique that can both power and propel their robot, ‘artificial blood’. You see the robot, which is designed to resemble a lionfish, see image below and my post of the 18th of April 2019, uses a pressurized fluid to activate motors in its tail and pectoral fins that enable it to move through the water.

Sift Robot Lionfish is powered by artificial blood! (Credit: Cornell Chronicle)

Such hydraulic systems are quite common in robots but here its only half the story because the fluid is also an ionized electrolyte solution that stores the energy needed to power the robot. As the electrolyte flows around the robot it passes through electric cells that use the ions to produce a voltage that powers the pumps that keep the fluid pressurized! This whole integrated approach is very similar to how our blood does provide the energy that enables our muscles to move.

The internal working of the soft lionfish robot. (Credit: Cornell Chronicle)

At the present time the robot lionfish moves rather slowly but it can keep moving for 36 hours. The engineers, led by Cornell Professor Robert Shepard, are hard at work on increasing the energy density of the system that will increase the robots speed. One advantage of the technique is that since their battery is a fluid it can easily be fitted into any spare space in the design increasing the total amount of energy contained within the robot.

Even though this technology is in its infancy the integration of energy storage and hydraulic force into a single fluid offers a great deal of promise. Living creatures have evolved over billions of years to make multiple uses of their body parts and now it seems that engineers are learning to follow the same paradigm.

Another ocean dweller whose lifestyle is so different from ours that engineers are intrigued by the possibility of it teaching them new ways to manipulate objects is the octopus. These intelligent invertebrates are well known for both the strength and delicacy of their many tentacles, attributes that engineers would like to emulate.

Cecilia Laschi at the Sant’Anna School for Advanced studies in Pisa Italy has succeeded in constructing a robotic octopus’s tentacle capable of behaving in a very lifelike fashion, undulating, elongating, curling and stiffening as required. The tentacle’s movements are created by an array of springs and metal cables; some composed of shaped memory alloys that will return to a predetermined shape when heated.

Doctor Laschi’s robotic octopus arm in action. (Credit: IEEE)

Doctor Laschi with her completed octopus soft robot. (Credit: IEEE)

Laschi is currently developing a compete robot octopus and has already developed a propulsion system based on the octopus’s jet. “When I started with the octopus, people asked me what it was for,” Laschi says. “I don’t know, but I’m sure if it succeeds there could be many applications.” Soft robots in general are finding more and more applications as engineers look more and more to nature for inspiration for innovation designs.

With the Dark Energy Spectroscopic Instrument (DESI) astronomers and physicists hope to learn something about the nature of the mysterious Dark Energy.

If you ask any astronomer or physicist what is the biggest, the most critical question, the biggest mystery in science today they will immediately reply, “What is dark Energy?” You see our observations tell us that the Universe is expanding while our theories of Gravity tell us that the expansion should be slowing down. But instead what we see is that the expansion of the Universe is accelerating. Something, some pressure is pushing the Universe ever farther apart and that ‘Dark Energy’ actually accounts for some 80-85% of all the energy in the Universe.

After the Big Bang Gravity should have caused the expansion of the Universe to at least slow down but instead something is causing to accelerate! Dark Energy! (Credit: NASA Science Mission Directorate)

The idea that we know so little about 80-85% of the Universe is more than just a bit embarrassing because since Dark Energy is the dominate part of the Universe it will obviously have the dominant effect to the eventual fate of the Universe. To understand why that is so I’m going to take a step back and review the history of the ‘Big Bang Model’ of the Universe.

One hundred years ago astronomers thought that the Universe was pretty static, neither expanding nor contracting. Physicists however didn’t like that picture because without something acting to keep the galaxies apart the force of gravity should pull everything together into a ‘Big Crunch’. Everybody was relieved therefore when the astronomer Carl Hubble found that the galaxies were in fact moving away from each other, the Universe was expanding.

The Famous image of Andromeda taken by Carl Hubble that allowed him to measure the distance and proving Andromeda was another Galaxy. (Credit: Space and Astronomy News Daily)

This was the start of the Big Bang Model where billions of years ago an incredibly dense, hot Universe expanded rapidly, cooled and then formed the galaxies we see today. The question then became whether gravity was strong enough to eventually bring the expansion to a halt, or had the Universe reached ‘escape velocity’ and the expansion would go on forever. In the first case once the Universe stopped expanding gravity would begin to cause it to contract leading to a Big Crunch. This was a known as a closed Universe. The alternative was an open Universe that would fly apart forever.

The difference between an open and closed Universe id the first expands forever while the second ends in a Big Crunch. (Credit: Astronomy Today)

The measurements needed to determine which model was correct were very difficult to make, so difficult in fact that it wasn’t until the 1990s that everyone was shocked to discover that the Universe was actually expanding faster. Something was pushing it apart and for lack of a better name that something was called Dark Energy. So we then had the biggest problem in science, what is Dark Energy?

The first thing that scientists would like to learn about Dark Energy is whether or not it is even a constant force or does it’s strength change with time? You see when Einstein formulated the equation of Gravity in his theory of general relativity, see equation below; he realized that mathematically the equation could have a constant added to it. Einstein gave that constant the symbol λ, and he calculated that the effect of that constant would look a lot like the Dark Energy we now see.

Einstein’s full equation for gravity with the cosmological constant lambda. The left hand side is the geometry of the Universe while the right hand side is the energy of the Universe. (Credit: WordPress.com)

Now if Dark Energy is just this ‘cosmological constant’ as Einstein pictured it then the expansion of the Universe will continue forever. If the strength of Dark Energy varies however, maybe even reverses itself to an attraction, then the ultimate fate of the Universe is still unknown.

However the measurements needed to determine whether the strength of Dark Energy varies with time are far more difficult to make than the measurements that discovered it in the first place. Still, astronomers have learned quite a bit in the last 25 years and advances in technology have made their instruments vastly more precise and sophisticated. It is with this improved technology that the Dark Energy Spectroscopic Instrument or DESI has been designed and constructed.

The setup of the Dark Energy Spectroscopic Instrument (DESI). New detectors and computer controlled fiber optics have been installed on the Mayall Telescope making it the most sensitive instrument for studying Dark Energy. (Credit: Spiedigitallibrary)

Retrofitted into the Mayall telescope at Kit Peak observatory outside of Tucson Arizona the DESI detector consists of a bundle of 5000 fiber optic cables, each with its own computer controlled positioning mechanism. The fiber optic cables lead to an array of 5000 spectrographs so that the combined telescope / detector will allow astronomers to accurately measure the position, magnitude and redshift of 5000 galaxies at a time.

The DESI instrument, black object upper right, installed on the Mayall telescope. (Credit: Popular Mechanics)

First light for the DESI instrument came in September of 2019 and the ambitious five-year observation program is now well underway. Once completed the DESI will have obtained the position and redshift of 35 million galaxies allowing scientists to produce a 3D model of a large section of the Universe. This model will then provide the data needed to answer the question of whether the strength of Dark Energy has varied with time.

And there are other instruments that will soon be coming online that will compliment the observations of DESI. The 4MOST telescope at the European Southern Observatory is similar to DESI while the Euclid space telescope will also be observing galactic redshift versus distance from orbit.

The Euclid space telescope will also study the nature of Dark Energy. (Credit: Wikipedia)

Now it is true that DESI will only tell physicists how Dark Energy changes with time nevertheless that information will be enough to enable them to eliminate many of the competing theories about its nature. So the theorists are anxiously awaiting the results of DESI and its companions, hoping that they give them direction in their effort to describe the entire Universe.

We’ve learned a great deal in the last 100 years about the structure and evolution of our Universe. I’ve little doubt that the next 100 years will bring just as many exciting discoveries.

Scientists around the world are hard at work doing research on removing CO2from our Atmosphere.

The evidence is mounting that the millions of tons of CO₂ and other greenhouse gasses that we’re pouring into the Earth’s atmosphere is causing an ever increasing amount of damage to the environment in which we all live. Of course if we’re going to avert the worst consequences of our behaviour the first thing we’re going to have to do is reduce those CO₂emissions as much as possible. The Paris climate accords are the promises that the nations of the World have made to cut back on CO₂ but so far few nations are keeping those promises even as the problem grows worse every day.

Can anybody seriously believe that all this crap isn’t destroying our planet somehow! (Credit: NPR)

Let’s be honest, politics being what it is the World’s governments aren’t going to really enforce any CO₂cutbacks until they are forced to by some real disasters occurring, and even then their response will be slow. By the time humanity does finally does start reducing the amount of CO₂ we put into the atmosphere there will already be so much up there that the harmful effects on the environment will only continue unless we start taking some of it out.

We need proven, efficient, large scale and most importantly cheap methods for removing CO₂ from the air. Because the need is so great you can probably guess that there are many scientists hard at work all over the world on that very problem. Today I’d like to discuss the efforts of just a few.

A lot of the research is taking place at the Massachusetts Institute of Technology (MIT) by Ph.D. candidate Sahag Voskian and his graduate advisor Professor T. Alan Hatton. Together the pair have developed a technique that closely resembles an ordinary battery in construction and application. The device consists of a stack of electrodes that are coated with a chemical compound known as polyanthraquinone that is composed of carbon nanotubes.

It is while the “battery” is being charged that the carbon nanotubes will grab CO₂ from an air stream blown across them. Then, as the battery is discharged the CO₂ is released by the nanotubes. So what you need is two batteries working in tandem to make the whole system work. One battery will absorb the CO₂as it is being charged, the other does the charging, releasing its CO₂ not back into the air but into a containment vessel. Once the two batteries are charged / discharged they can then be flipped, starting the process all over again.

The CO2 removal ‘battery’ developed at MIT. CO2 enters the left side of the lower battery and is captured as that battery is charged. Then as the upper battery is discharged it releases the CO2, upper battery. (Credit: CNet)

Now the cycle is not 100% efficient, and more energy is usually needed to produce the air flow. Nevertheless Voskian and Hatton estimate that the operating costs will be rather small. Right now the most expensive part of the whole proposition would probably be the carbon nanotubes, which are in fact quite costly to produce. However in large-scale production the costs could come down considerably and remember the carbon nanotubes can be used over and over again so you only have to pay for them once. We’ll just have to wait a see if Voskian and Hatton do have a viable solution for removing some of the CO₂ already in our Atmosphere.

Artists impression of a large scale CO2 removal system. (Credit: MIT News)

Other scientists are taking a more natural approach, developing what they call an ‘artificial leaf’. Led by engineering professor Yimin Wu of the University of Waterloo the team also contains scientists from the California State University, Northridge, and the City University of Hong Kong along with the Argonne National Labouratory in Illinois.

With such an impressive team you’d expect some impressive results and what Professor Wu’s team seems to have delivered. According to Wu. “We call it an artificial leaf because it mimics real leaves and the process of photosynthesis. A leaf produces glucose and oxygen. We produce methanol and oxygen.”

Instead of Chlorophyll the artificial leaf uses a chemical compound called cuprous oxide (Cu₂O), which is ground into a powder and mixed into water. When CO₂ is blown into the water the cuprous oxide serves as a catalysis separating the carbon and oxygen, releasing the oxygen and producing methanol. The methanol can then be collected and used as a fuel.

The Artificial Leaf in action. (Credit: The Independent)

One drawback to the artificial leaf is that, unlike the MIT battery, it requires a high concentration of CO₂ in order to work efficiently. This would restrict the usage of the artificial leaf to such places as power plant smoke stacks and car exhausts but once the carbon is collected it is already in a useful form.

There’s still more work to be done. Professor Wu and his team now want to increase the methanol yield while packaging the reaction in a more commercial form, one ready to be used in the fight against the greenhouse gasses causing climate change.

But you know, the artificial leaf got me thinking about the one technology that we could all be using right now to take some of the CO₂ out of the air we breath. Real leaves, as in those on real trees. There are now a number of local and world wide organizations promoting the planting of trees as something anyone can do to help fight climate change. In urban locations the trees have the added advantages that they can absorb water during heavy rainfalls to help reduce flooding while even helping to cool entire cities by providing shade instead of just getting hot like concrete and asphalt. So if you want to do you part to help fight greenhouse gasses just take a look around your yard or block. Do you see any places where a nice tree could go?

Here’s something we can all do right now to help reduce CO2 in the air! (Credit: Armenian National Committee of America)

Book Review: ‘What a Fish Knows’ by Jonathan Balcombe. Plus, some of my pictures of the transit of Mercury.

Fishes are not only the oldest class of vertebrate animals they are the most diverse having some 30,000 known species. That’s about as many species as all of the amphibians, reptiles, bird and mammals put together. They are also, according to author Jonathan Balcombe, the least understood, not only by the general public but by professional biologists as well.

Cover of ‘What a Fish Knows’ by Jonathan Balcombe. (Credit: Amazon.com)

Mister Balcombe certainly knows his fish. As the Director of Animal Sentience at the Humane Society Institute for Science and Policy Mister Balcombe is an unabashed supporter of the rights of all animals, especially fish. That’s not an easy job considering that we humans annually kill around a estimated 2 trillion, that’s trillion with a T, fish. Many of these fish we don’t even eat. A large fraction of those billions of fish are simply ground up to be used as food for the animals we grow, both land animals and the stock of the rapidly growing fish farming industry.

Human beings annually kill an estimated 2 Trillion Fish! (Credit: ESA Business Applications)

Even so there is still a large fraction of commercially captured fish that are completely unwanted. Caught by nets or hooks they are brought on board ships and usually left to die before they are thrown back in the water. These fish, along with dolphins, squid, crustaceans and coral, even seabirds are known in the fishing industry as bycatch. Of no value commercially they die simply because we consider it too much trouble to do anything to avoid killing them.

Just a few of the statistics of the damage we cause unintentionally to marine life! (Credit: ReefCl)

This poor sea turtle is going to die simply because it was unlucky enough to get caught in one of our nets. (Credit: University of Miami)

The sheer brutality of the way we use fish is one of the arguments Mister Balcombe employs in order to get we, his readers to care about our finny fellow creatures. Balcombe’s other technique is to simply teach us something about fish, the idea being that the more we know about someone or something the more likely we are to treat them as a fellow creature, even if they do have fins instead of legs.

So most of ‘What a Fish Knows’ consists of a thorough review of what we know about fish, their anatomy, their sensory view of the world, their intelligence, social behavior and parenting skills. Using the results of almost two hundred peer reviewed research papers about fish Mister Balcombe entertains us as much as teaches us about what a fish does know. Oh, and if you didn’t know that fish have intelligence, or social behavior or parenting skills you really should read this book.

Mouth brooding fish will literally defend their young by hiding them in their mouth! (Credit: The Fisheries Blog)

As I said earlier Mister Balcombe is an advocate for the rights of fish but I must say that with seven billion hungry human beings on this planet, many of whom need more protein in their diet, there’s a limit to how far we can go with the ethical treatment of animals. The most important thing in my opinion is to begin using fish in a sustainable fashion. Many of the species of fish we most enjoy eating are being driven to extinction by commercial overfishing.

That’s why I’m a big advocate for fish farming, even though I do recognize such problems as pollution caused by fish farms. At the same time we can certainly do something to reduce the sheer waste of life we cause with bycatch. Another horrible practice is the catching of sharks in order to cut off their fins for shark fin soup, and then tossing the still living animal back into the water to die in agony.

Many fish farms are along the coastal areas of the world. (Credit: WordPress.com)

Other fish farms are well inland. (Credit: Cherokee,NC)

Life implies death, and even if we didn’t eat fish they would still end up being eaten by something. But we consider ourselves to be a bit above the moral plane of ‘nature, red in tooth and claw’. To justify our high opinion of ourselves we must do more to treat our fellow creatures more humanely.

Postscript: Well Monday was the transit of Mercury, did you get to see it. The clouds here in Philadelphia held off for about the first half of the transit, long enough for me to get a few good pictures of this celestial event. See below.

The transit of Mercury on 11 November 2019. The planet is only a tiny dot compared to the immensity of our Sun. (Credit: R. A. Lawler)

Even in closeup the planet still seems tiny! (Credit: R. A. Lawler)

I know my images can’t compare with those you can easily find at NASA or other websites, but I think they’re better ’cause I took’em!

Paleontology News for October 2019.

There have been some important fossil discoveries lately that span nearly the entire time period of multi-cellular life on Earth. I think I’ll start with the earliest and work my way forward in time.

We usually think of complex social behavior as being a recent development in the history of life. After all we have the most complex societies of any species and we’re one of the youngest of Earth’s creatures, right?

Humans have been social as long as we’ve been Human. (Credit: History.com)

Well it is worth remembering that some insects like ants have been living together in complex hives for around 200 million years and we now know that many species of dinosaurs traveled in herds for protection. So obviously some forms of social behavior predate human beings by quite a long time.

However some animals have been social a lot longer than we have. (Credit: Phys.org)

Now a new series of fossils from Morocco is providing evidence that social behavior existed as far back as the lower Ordovician period, about 480 million years ago. The fossils shown a large number of individuals of the trilobite species Ampyx priscus arranged in a line with the front end of their bodies all pointing in the same direction. The clear indication is that these creatures were moving together in a very orderly line, a behavior requiring considerable neural and sensory ability.

Trilobites of the species A pricus moving together in a line 480 MYA. (Credit: The New York Times)

The reason why these trilobites were moving together in a line will probably never be known for certain but the fact is that arthropod species like spiny lobsters, ants and even caterpillars are known to behave in a very similar fashion today. These trilobites provide another example of how old doesn’t necessarily imply simple or primitive.

One of the critical events in the history of life on this planet has to be the moment when the first vertebrate animal, a fish, climbed out of the water and gingerly set foot on the land. All land dwelling bony animals, all amphibians, reptiles, including the dinosaurs, birds and mammals, including you and I are beholden to that ancient creature.

An artists illustration of what the first vertebrate to step onto land may have looked like. (Credit: Phys.org)

So it’s not surprising that paleontologists are keenly interested in learning as much as they can about those early land vertebrates. The recent discovery of a new species of tetrapod, that is a four-limbed animal, gives an insight into what kind of creature may have been the first to make that historic step. Discovered in the Sosnogorsk formation along the banks of the Izhma River in the former Soviet Republic of Komi the animal has been dated to about 372 million years ago during the Devonian Period.

Artists impression of the recently discovered Terapod from the Komi Republic. (Credit: Daily Mail)

Named Parmastega aelidae the animal is a strange mixture of both fish and land animal characteristics. For example the placement of its eyes on the top of a flat skull clearly indicates an animal that is watching what is going on above the waterline. At the same time however the animal’s shoulder girdle is made of partially cartilaginous bones, making those bones too weak to be able to support a land animal. So P aelidae may have been a water animal whose prey lived out of the water. A modern example would be a crocodile and indeed the long snout filled with sharp teeth of P aelidae strongly resembles that of a crocodile.

A comparison of the skull of the terapod (r) to that of a modern crocodile (l). (Credit: Daily Mail)

A fossil jawbone of the terapod showing numerous sharp teeth. (Credit: Phys.org)

The discovery of such fossils as P aelidae gives us further knowledge in our quest to understand how our ancestors evolved to become the dominant kind of life on land.

Another critical moment in the history of life on Earth surely came after the asteroid collision that led to the extinction of the dinosaurs along with 75% of all species of life. The questions of how quickly did life recover from that disaster, and what kind of animals became dominant now that the dinosaurs were gone are key to our understanding the natural world today? Paleontologists know that in order to answer these questions they need to find fossil sites from the time immediately after the asteroid strike.

The asteroid that killed the dinosaurs landed in the Yucatan peninsula of Mexico forming a crater 300 km wide. (Credit: Research.utexas.edu)

Just such a fossil site was recently discovered by paleontologists Tyler Lyson and Ian Miller of the Denver Museum of Nature and Science just outside the nearby city of Colorado Springs. The location, known as Corral Bluff is yielding a treasure trove of fossils from a time less than a million years after the asteroid strike. The finds include over 1,000 mammal fossils from 16 different species along with reptiles, birds and 6,000 plant fossils. The most important finds discovered by the researchers consisted of dozens of delicate mammalian skulls.

Doctors Lyson (r) and Miller (l) searching for mammal fossils at Corral Bluff. (Credit: KPBS)

While the fossils are still being studied a few conclusions can be reached. During the reign of the dinosaurs mammals remained small, rare and nocturnal creatures no larger than a squirrel, about one kilogram maximum. The fossils obtained from Corral Bluff however show that is less than a million after the dinosaurs were gone mammals had already greatly increased in both size and number with one of the species discovered estimated as having a mass more than 50 kg.

Artists impression of one of the little mammals that repopulated the world after the extinction of the dinosaurs. (Credit: USA Today)

Some of the mammal fossils found at Corral Bluff. (Credit: Reuters)

The fossils from Corral Bluffs give witness to how quickly the mammals were evolving to fill up the ecological niches left vacant by the extinction of the dinosaurs. At the same time the paleontologists are making other discoveries as well, among them the remains of the earliest known legume, a pea plant that might very well have provided high protein food for some of the growing population of mammals.

The history of life on Earth is both long and complex but paleontologists don’t mind that at all. It just mean that there are many more fascinating discoveries waiting to be made.

Did social inequality begin during the Bronze Age? New results from archeology in Germany may point toward an answer.

“All animals are equal,” George Orwell declared in his novel ‘Animal Farm, “But some animals are more equal than others!”

Is Social inequality a necessary condition of having a society? (Credit: George Orwell)

The question of when and how did social inequality arise in human populations has been asked ever since we humans began to live in large societies. Now let me be clear here, I’m talking about social inequality, the kind of inequality where a small but recognizable portion of a human population dominates and forces obedience from the greater part of their society for periods of time longer than a single human lifespan.

We can see the beginnings of this inequality in the social behavior of our closest relatives. In a troop of chimpanzees or gorillas the alpha male and his close companions push the rest of the group around establishing a easily recognizable pecking order. However it is rare for that dominance to be passed directly to the son of the alpha male. Strength, not pedigree is the key to being on top in such primitive societies.

Amongst our primate relatives the Alpha Male maintains his position through violence and intimidation. (Credit: The Conscious Resistance)

The opinion of most anthropologists is that long term social inequality requires material wealth. Objects such as tools or pottery but most importantly weapons that an alpha male can pass on to his son(s) giving them an advantage over the other members of their tribe. Eventually the ability to pass on the ownership of flocks of domesticated animals or land itself will bring with it the establishment of actual economic classes, rich and poor.

Now Stone Age societies are known to have possessed a degree of material wealth in the form of stone and bone tools and in later periods even pottery. However stone tools and pottery break quite easily and are of little permanent value.

Stone Age Tools can vary greatly and be quite useful. However they usually don’t last very long requiring constant replacement. (Credit: Peter Ghiringhelli)

Metal makes all the difference. Metal tools can last for many years with care and a metal weapon will not only keep its edge far longer than a stone one but can even be resharpened when it does become dull! The long-term value of metal objects appears to have been a real game changer in the evolution of human civilization.

Bronze Age Weapons can last for decades and be passed down father to son helping to concentrate power within a family or clan. (Credit: Monaghan County Council)

Therefore, the argument from anthropologists goes, the first evidence for the development of social inequality should be found in the Bronze ages. The question is therefore; does the evidence of the archeological record support that argument?

There is a wealth of data from the Bronze Age civilizations of the eastern Mediterranean that seems to confirm this hypothesis. The pharoses of Egypt were treated as god-kings who could command tens of thousands of commoners to build their massive pyramid tombs while the Hittite and Mycenaean Greek Kings lived in enormous palaces surrounded by the common folk who laboured for them.

But what about the rest of the world, is there any evidence for the rise of social inequality in the rest of Bronze Age Europe for example? It’s that question that makes the recent study of the Late Neolithic to Early Bronze age site in the Lech Valley in Germany so interesting.

Authored by Alissa Mittnik and Johannes Krause of the Max Planck Institute for the Science of Human History along with Philipp Stockhammer from the Ludwig-Maximilians-Universitaet in Munich, the study makes extensive use of the latest archaeological techniques, radiocarbon dating, DNA analysis and isotope analysis of tooth enamel along with more traditional methods.

The Bronze Age sites in the Lech valley consist of several large homesteads, numerous smaller farms and critically, several cemeteries. Those cemeteries yielded the remains of 104 individuals that were radiocarbon dated to a period between 2800 and 1300 BCE, spanning the late Neolithic to early Bronze Age.

The excavation of a Bronze Age grave in the Lech Valley of Germany. (Credit: Alamy Stock Photo)

The presence of a wide assortment of grave goods in some of the graves allowed the identification of upper class versus lower class individuals according to criteria employed since the beginning of archeology. For example the presence of bronze daggers or axes in a male grave, or metal jewelry in a female grave would indicate a member of the warrior elite while few or no grave goods is indicative of a servant or serf.

Some of the Bronze tools and weapons unearthed in Germany. (Credit: K. Massy)

Once a set of remains had been classified as to its social status DNA extracted from teeth or bone was used to determine their family relations. The researchers discovered that the upper class warrior individuals had no family relationships at all to those of the lower class. At the same time they were able to establish father to son sequences within the upper class that could last as long as five generations. Also, isotope analysis of chemicals extracted from the tooth enamel of both the high-class males and all lower class individuals showed that they were all native to the Lech valley.

A finely made Bronze Age dagger. (Credit: K. Massy)

The surprise of the study however turned out to be the examinations of the high-class female remains. Genetically the high-class women showed no relationship to either the high class or lower class men! In addition when the tooth enamel of the high-class women was chemically examined it was found that they were foreign born, some coming from as far away as modern Czechoslovakia, more than 500 kilometers away. The implication is that these women were brought to the Lech valley to be wives for the high-class men while the daughters of the high class were sent elsewhere to marry.

High class women also had elaborate grave goods buried with them. Here is a decorative pin found in the grave of one foreign woman. Credit: K. Massy)

This cultural tradition of aristocratic families sending their daughters to marry into families at great distances is believed to have served two purposes. First it prevented inbreeding within the upper class while at the same time it helped to establish cultural and even trading links with other communities. While such nuptial customs are well established for the late Bronze and through the Iron Age into the Roman period this study provides the first comprehensive support for the existence of these traditions at the very beginning of the Bronze Age.

One Artists impression of life in Bronze Age Germany. (Credit: Philipp Stockhammer)

With every new excavation, with every new technique developed to examine the finds unearthed the science of Archaeology is discovering more and more about the beginnings of human civilization. This includes the story of when and how human social classes first developed.

Skywatch Alert: Transit of Mercury on the 11th of November 2019! (CAUTION, never look directly into the Sun without protective eyewear!!!)

Two years ago in August of 2017 the United States was treated to the amazing celestial event of a total eclipse of the Sun that traveled across the nation from Oregon to South Carolina. (See my post of 24Aug2017) Of course everybody knows that a Solar eclipse only happens because the Moon can pass in front of the Sun blocking out its light.

One of the pictures I took during the Eclipse of August 2017. (Credit: R. A. Lawler)

The Moon isn’t the only astronomical body that can pass in front of the Sun however. The two inner planets Mercury and Venus can also cross between the Sun and our planet. But because they are so much further from the Earth than our Moon is they only cover up a very small portion of the Sun’s disk, so small you’d never know that it was happening unless you purposely look for it.

Also because Venus and Mercury are further away than our Moon transits occur less frequently than eclipses. While a Solar eclipse happens somewhere on Earth almost every year there will only be 14 transits of Mercury and only two transits of Venus this entire century. The transits of Venus are already past by the way, the next one is in December of 2117! And because the two planets are further away they appear to move more slowly across the face of the Sun, taking hours to complete a transit instead of the four minutes of total eclipse I got to see in 2017.

Some of the astronomical details of the November 11th transit of Mercury. (Credit: F. Espenak)

I’ve been fortunate enough to see both kinds of transit, a transit of Venus back on the 8th of June in 2004 and a transit of Mercury on the 9th of May 2016. I had not yet bought a Solar telescope back in 2004 so I have no pictures of the Venus transit but I had all my equipment ready in 2016 so even though the day was pretty cloudy I did manage to get a few pictures. (See image below)

Picture of transit of Mercury I took in June 2016. (Credit: R. A. Lawler)

As with a Solar eclipse whether or not you are able to see a transit depends on whether the Sun is out, in other words is it daylight where you live while the transit is happening. The map below shows how much of the transit will be visible in your location.

The November 2019 transit of Mercury will only be see in certain parts of the World. The map above indicates where! (Credit: F. Espenak)

Once again I’m going to be lucky because the eastern US gets to see the entire event, as does the whole of South America. For the middle part of North America and the west coast however the transit will already be happening as the Sun rises in your location. For Europe and most of Africa the opposite is true, you will be able see the beginning of the transit in the late afternoon but the Sun will set before the event is over. Asia and Australia I’m afraid you’re out of luck this time around but the entire transit is going to be live streamed so check out the link below. https://www.virtualtelescope.eu/2019/10/16/the-11-november-2019-mercury-transit-online-observing-session/

If you are going to try to see something of the Mercury transit yourself PLEASE DO NOT LOOK DIRECTLY AT THE SUN WITHOUT EYE PROTECTION!! Only a fool without a bit of common sense looks directly at the Sun without eye protection. As evidence of that fact the image below shows Donald Trump watching the 2017 Solar eclipse without eye protection.

Donald Trump foolishly watching the Solar Eclipse of August 2017 without eye protection. (Credit: Washington Post)

If you happen to still have your eclipse glasses from 2017 they will protect your eyes although Mercury will only appear as a tiny dot on the Sun’s disk. If you have lost your glasses or if you’d like a better view of the transit remember once again that the event will be live streamed. Now all I need is some good weather, I’m keeping my fingers crossed.