Volcanic eruptions may have disrupted the stability and prosperity of of ancient Egypt by triggering revolts (Source: heritagedaily.com
Major revolts in ancient Egypt may have been triggered by volcanic eruptions that prevented the Nile from its usual summer flooding.
That’s according to research conducted by TCD and Yale University historians who examined evidence from ancient Egyptian writings during the Ptolemaic period, as well polar ice-core records and climate modelling.
The researchers believe that this research, published in Nature Communications can improve understanding of how societies respond to climate shocks.
Egypt’s Ptolemaic era, which ran from 305 BC to 30 BC is famed for its prosperity, cultural and material achievement, rulers such as Cleopatra, and was home to the great city of Alexandria.
The success of Egypt during this glorious period of its history was directly linked with the river Nile, and its annual summer flooding, which provided the water, and irrigation necessary to support the region’s thriving agriculture.
“It is very rare in science and history to have such strong and detailed evidence documenting how past societies responded to sudden hydroclimatic shocks,” said Dr Francis Ludlow, from the TCD School of Histories and Humanities, who jointly led the study.
“To fully understand how sudden environmental pressures could act to destabilise society, the historical context is key, and in this case included pressures from high levels of taxation and ethnic tensions that likely coalesced to trigger revolt at times of agricultural failures from insufficient floodwaters,” Dr Ludlow added.
The researchers were able to show that large volcanic eruptions disrupted the African summer monsoon and reduced Nile river flow. This helped to trigger economic and political instability, in particular to trigger revolts against Ptolemaic rule of Egypt and limiting that state’s ability to wage warfare.
The authors also provided evidence of further social stresses through the increased sales of family-held land following eruptions. This has been documented in the surviving records, and likely to have occurred because families were unable to meet state taxation demands after failed harvests.
The study, according to the authors, also has significant implications regarding how societies will respond to future climate change, and more specifically about how the nations that depend upon the summer flood waters of Nile might manage under the impact from the next big volcanic eruption.
The Allen Telescope Array in Hat Creek California is set up to search for signs of extra-terrestrial intelligence (Image source: Sky & Telescope)
For millions of years – as long as humans have existed and gazed upwards – people will have questioned are we alone in the Universe? Yet, it is only in the past 60 years or so, with rapid technological advances, that it has become possible to make serious attempts to answer that age-old question.
Listen to interview with Myles Dungan on The History Show, RTE Radio 1 (broadcast 2/04/17)
Ancient
The ancient Greeks, the foundation stone upon which much of our western way of life today has been built, were the first, in the west at least, to consider the possibility that the Universe was infinite and that it contained an infinite number of civilisations.
The arrival in the 16th century of the Copernican model of our Solar System, where the Earth revolved around the Sun, impacted on our thoughts of ET life too.
This radical science, which place the Sun at the centre of the Solar System, not the Earth, implied that our planet was not perhaps as important as we had thought.
If Earth was just one planet of several orbiting the Sun, and not at the centre of everything, then why could there not be life, like us, on other similar planets?
This, of course, caused complications for some established religions, as if there was life, like us, on other planets, then had Jesus come down to save them too?
There things stood, with lots of questions, but no ability to answer them, for several centuries until the second half of the twentieth century.
Principles
In the 1950s, at the height of Cold War paranoia, the number of reported sightings of UFOs increased dramatically across the United States.
In 1959, two young scientists at Cornell University decided to try and take a serious scientific look at how mankind might try to tune in to alien communications.
The paper appeared in Nature, one of the world’s top scientific journals, and it was called ‘Searching for Interstellar Communications’.
This paper changed everything because it established the scientific principles by which scientists might try to find, and listen in to alien communications, if they existed.
The authors, Guiseppe Cocconi and Philip Morrison were both physicists based at Cornell University in upstate New York. They said that the possibility of extra-terrestrial ‘intelligent’ life couldn’t be determined, or ruled in or out. However, given that mankind evolved it was likely that other intelligent creatures evolved too, on planets near a Sun. Some of these civilisations might, the authors said, be more advanced than our own and may want to contact us and other intelligent beings that resided on planets – like them – close to a warm Star.
The two physicists considered how intelligent extra-terrestrials might make contact with us, and decided that electromagnetic waves, which travel at the speed of light and are not easily knocked off course, would be the most logical way to transmit a message.
Furthermore, they decided that the most likely frequency the aliens would broadcast on would be 1,420 megahertz as that is the ‘emission frequency’ of hydrogen, the most abundant element in the Universe. This is the frequency of the radio wave emissions given off when an atom in an element, in this case hydrogen, is given off as the element moves from a high energy atomic configuration into a lower energy configuration.
The aliens, the logic went, would chose this frequency because they knew other intelligent beings would also understand its importance and tune in accordingly.
SETI
The paper inspired a now-famous astronomer called Frank Drake to perform the first scientific experiment to search for extra-terrestrial intelligence. That was 1960.
Drake, is still alive, aged 86, and an active astronomer, and considered the Father of SETI the Search for Extra-terrestrial life, and the SETI Institute in the USA.
Drake pointed a radio telescope at two ‘nearby’ stars called Tau Ceti and Epsilon Eridani to see whether there was anything being broadcast from planets orbiting these Sun-like bodies in the hydrogen emission frequency from that location. There wasn’t.
Today, the SETI Institute, based in Northern California, has access to a $30 million array of telescopes, funded by Paul Allen, the co-founder of Microsoft. It has a permanent staff of scientists, and is supported by donations and computer power by SETI enthusiasts all over the world. It is not reliant on US taxpayers’ support.
Drake, apart from founding SETI, is also famous for producing something called the Drake equation along with Carl Sagan, to predict how many civilisations there might be in the Universe, based on known parameters.
In 1961, when the Drake equations was first produced, it predicted there was from 1,000 to one billion such civilisations, and the range was down to the fact that the parameters were nebulous.
The Drake equation has become more accurate over the years, based on better knowledge of parameters such as how often Sun-like Stars form, and how many of these stars have planets. But we still don’t know how precisely life begins, even on Earth, or what fraction of life will evolve to become intelligent.
Criticism
The implications of the Cocconi and Morrison article took time to be absorbed by the mainstream scientific community, but eventually, in 1971, NASA got on board by setting up Project Cyclops at NASA. This was the first formalised, publicly-funded research project into searching for ET life.
The funding wasn’t enough for scientists at Cyclops to do a great deal, but even at its low level of funding, it soon came under political attack.
In 1978, Senator William Proxmire bestowed one of his infamous ‘golden fleece’ awards on the SETI programme, deriding it as a waste of taxpayers’ money.
In 1981, a Proxmire amendment killed off SETI funding for the following year with Proxmire saying that it was a silly search for aliens unlikely to produce results.
In 1993, NASA got back into SETI work, this time with the High Resolution Microwave Survey Targeted Search programme. But, again, this project too came under political attack and lost is operational funding just one year after it began.
It wasn’t just politicians who were critical of SETI work, scientists were critical too, who supported the view outlined by the late nuclear physicist Enrico Fermi.
Fermi, who had died in 1954, did not accept the view (held by many at SETI) that the Universe was teeming with life, based on its size, and number of planets near Stars.
Fermi said that if the SETI people were to be believed, and the Universe was teeming The Earth was 4.5 billion years old, Fermi had said, and there was no evidence of extra-terrestrial life visiting here in all that time.
He had asked the question if there is so much life out there, ‘where is everybody’. It was a simple, yet, devastating riposte to the Drake equation.
Fermi had come up with his idea in 1950, but many scientists still point to it.
Evidence
Yet, Fermi was not alive when two things happened, both in the mid-1970s, which are the best pieces of evidence for the existence of extra-terrestrial life.
The first story concerns an experiment that took place when the Viking landers landed on Mars in 1976. Some readers will remember the amazing colour pictures of the surface of Mars shown on TV at the time.
Viking 1 and Viking 2 were NASA space probes sent to Mars for the sole purpose of determining whether life existed on the planet.
One of three experiments on board worked was set up to see if the soil contained microbes. If it did, the life forms in the Martian soil would ingest and metabolise the nutrients and release either radioactive carbon dioxide or methane gas which could be measured by a radiation detector on the space probe.
The minute the nutrients were mixed with the soil sample there was a huge reaction with something like 10,000 counts of radioactive molecules being produced. This was a huge spike because the radiation background on Mars was 50 or 60 counts.
The experiment was, thus, positive for life, but NASA did not announce it had found life because the other two experiments on board which were negative for life.
The other piece of ‘evidence’ that is put forward concerns what is called the ‘Wow signal’, which was received by the Big Ear Telescope on 15th August 1977. The telescope was scanning for signals coming in from potential ET intelligent beings.
This was a strong narrowband signal which appeared to come from the constellation Sagittarius, and was in the 1,420 MHz frequency band. It was precisely the sort of signal that the SETI researchers were looking for as being of ET origin.
Jerry Ehman, a volunteer astronomer working with SETI spotted this massive, powerful, narrow band Wo signal on the paper readouts he was going through while sitting at his kitchen table a few days later.
Ehman was stunned by the signal and was so taken back by it that he wrote the comment ‘Wow’ in the paper margins, hence the name Wow signal.
The signal lasted 72 seconds, then the Earth rotated, the signal dropped out of view of the telescope, and when the same region of sky came into view again, it was gone.
The signal helped inspire the film Contact (1997) starring Jodie Foster.
Jerry Ehman went through every conceivable possible earthbound source for the signal, such as nearby military and civilian communications, but nothing could explain it. It remains the strongest candidate ever detected for an alien radio transmission.
Recent
The biggest thing to happen in recent years was the announcement in 2015 of $100 million privately funded search for ET life over 10 years, or about 10 million per year. This is big even compared to the annual funding for SETI of about 2 million dollars per annum. The Breakthrough Listen and Breakthrough Message initiatives are supported by the Russian internet investor and physicist Yuri Milner and supporter by big names like Stephen Hawking, Martin Rees and Frank Drake.
This will survey the one million stars in the Milky Way closest to Earth, as well as the 100 closest galaxies for signs of intelligent life beyond Earth, in the form of artificial radio or optical transmissions that cannot be explained by natural phenomenon.
The advance of technology and our ability to scan more areas of our vast galaxy and Universe mean that people like Seth Shostak, an astronomer at SETI believes that we will have discovered ET life, intelligent or not, inside the next 20 years.
Irish scientists, episode 3: Charles Parsons, inventor of the steam turbine engine was first broadcast on East Coast FM on 26th November 2016
Charles Parsons’ Turbinia yacht, pictured here, outpaced the assembled British navy at Spithead in 1897 with its steam powered turbine engine (Source: Wikimedia Commons)
Charles Parsons is considered to be in the top five of Britain’s greatest engineers of all time, by virtue of his enormous contribution to sea travel, and the shipbuilding industry, and making electricity available to the masses.
Parsons’s huge impact on the world has been far less heralded in Ireland, his native land. Hew grew up and spent his early adult years at his family’s residence in Birr Castle Co. Offaly before moving to England.
The greatest achievement of his stellar engineering career was the invention of the steam turbine engine in 1884, an entirely new type of engine, which extracted thermal energy from pressurised steam in an ultra-efficient manner.
This thermal energy could be converted, through a series of intermediary steps, into electrical energy in such an efficient manner that, it became possible, for the first time, to generate enough electrical energy to make it available to the wide mass of people, not just the well-to-do elite.
Today, 90% of the electricity in the USA is still generated through steam turbine engines.
This engine also transformed the nature of sea travel, as steam turbines could provide the power necessary for large ships to cross the Atlantic far quicker, and for passengers to travel in comfort without rattling, shaking and noise.
The steam turbine was famously put into Parsons’s yacht, the Turbinia, and used to outpace the assembled British naval fleet at Queen Victoria’s Diamond Jubilee Fleet Review at Spithead in 1897.
After this unsolicited, but powerful demonstration of the power that a steam turbine could provide, the British navy decided that it would commission the turbine to be used in its new generation of battleships, the Dreadnoughts (launched in 1906)
This helped to provide Britain with an edge in its naval arms race with Germany in the run up to World War 1.
This was first broadcast on East Coast FM on 19-11-2016
The Mars Curiosity Rover, pictured here, navigated its way to the surface of Mars in August 2012 thanks to equations invented by an Irishman in 1843 (Credit: NASA)
This episode covers the story of a Dubliner born in 1805, who became one of the greatest mathematicians the world has ever seen.
Hamilton invented mathematical equations, called quaternions, in 1843 which are still used today to navigate and land spacecraft (eg the Moon in 1969 and Mars in 2012) and as software ‘under the hood’ which depicts the relative movement of figures in 3D space in the top selling computer games.
GPS in cars, is largely based on Hamilton’s mathematics, and radio waves were predicted by James Clarke Maxwell before they were invented based on Hamilton’s totally unconventional, brilliant new mathematics.
Hamilton was objects rotate in 3D space, dared to imagine it. Came up with quaternions, totally unconventional and knocked traditional mathematics on its head. Thinking about this problem for years.
Mathematicians thought he was crazy, didn’t accept it, but then came to be called the ‘liberator of algebra’ – new way of thinking of mathematics.
Hamilton connected to fact we can hear audio on the radio, James Clark Maxwell predicted oscillating waves of energy traveling at speed of light – radio waves were detected, used by maxwell to predict these waves exist before they were found.
Hamilton was a brilliant, popular scientist. He was moody; a romantic, with a dark side, who survived an early crisis in his life to go on achieve great things.
Click above to listen to discussion on the diesel engine, past, present and future, above on Today with Sean O’Rourke
Click above to listen to discussion with Ann-Marie Donelan, presenter of The Grapevine show, on CRC 102.9 FM
The diesel engine was designed more than a century ago, yet it remains the engine that, more than other, powers our 21st century world.
The diesel is used everywhere from mines, cars, trains, ships and lorries, yet it has changed little since it was invented by Rudolf Diesel in 1892.
There are many remarkable aspects to the history and development of the diesel, still the world’s favourite engine.
A Volkswagen Passat CC car is tested for its exhaust emissions at a testing station in London (Credit: John Stillwell/PA)
News
Diesel engines are in the news because it is a diesel engine that is at the heart of the Volkswagen pollution emissions scandal, which is still playing out.
The background to the scandal is the tightening restrictions by the US, the European Union and others on emissions of certain gases in cars.
There is a dual demand on car manufacturers to produce cars that perform well, run smoothly, are fuel efficient, and ‘clean and green’.
Car manufactures must deliver both, because if they don’t, they their cars will be taxed heavily, and people don’t want to buy ‘dirty’ cars.
The problem is, according to some engineers, that our law-makers were essentially asking VW and the other car makers to do the impossible.
We can’t have our cake and eat it, the engineers say. We can either have clean, green, fuel efficient cars, or we can have high performing cars, we can’t have both.
People buy diesel cars in particular, because they want to buy a car that is cheaper to run, reliable, fuel efficient, and performs well.
The noose has been tightening around the necks of VW and others because the regulations on emissions have been steadily tightening.
At some point, a decision was obviously made that the only option – faced with the impossible – was to cheat the regulator’s tests.
It was relatively easy to cheat the tests, as EPA car tests in the US are standard, and done on machines. Who else is doing this we must ask?
A 1906 diesel engine built by MAN AG (Source: Wikipedia)
How does a Diesel engine work?
Diesels work by converting chemical energy in diesel fuel into mechanical energy which is put to use by the engine.
The energy in diesel is released following an uncontrolled explosion when it comes into contact with very hot, pressurised air.
This ignition, or explosion occurs when diesel, which has first been atomised is sprayed by fuel injection into the compressed air.
This creates energy which initially drives a linear motion, up and down, of a piston, which is transferred to a rotary motion of the crankshaft.
Because the diesel ignition is uncontrolled, it is not smooth like a petrol engine, and the cylinders must be contained inside a heavy engine block.
The energy from the ignition pushes the piston down, inlet valves open, and fresh air is allowed into the engine from the outside.
The diesel engine effectively takes an ‘in breath’.
When the energy is expended, the piston moves up again, the ‘second stroke’ of the engine, and the fresh air is compressed.
The inlet and exhaust valves are closed so that the air cannot escape and is compressed. The temperature and pressure of the air rise to a value that is higher than the self-ignition value of the diesel.
This means the diesel ignites immediately on contact with the pressurised air. The air is circulated by a bowl (during the compression stroke) at the top of the piston which ensures an even spread of fuel.
Each engine cycle requires two strokes, breath in, and breath out if you like. However, many diesel engines are four stroke so that the energy produced is more evenly spread, and there is less shaking.
There are different amounts of energy produced by the uncontrolled explosion of diesel via each stroke. The more strokes, the more even the energy spread.
In a four-cylinder engine, with 4 driving pistons, there can be 4 power strokes happening at the same time, so the power stroke is always present in the engine.
The more cylinders a diesel engine has, the smoother it will operate. A heavy flywheel (timing belt) also helps to smooth out non uniformity of power, as do various weights applied to the crank shaft.
The operation of a diesel engine is all about producing high temperature and high pressure air continuously.
Rudolf Diesel, the inventor of the diesel engine (Source: Wikipedia)
Inventor
It was invented by German engineer Rudolf Diesel, who took out patents on a diesel engine in 1892 and 1993.
Diesel became famous and successful very quickly, as his engines went into production all around the world.
In 1897 the American brewery magnate Adolphus Busch acquired a license to make the machine for about one million marks, or about $50,000.
Soon the Busch Diesel engines were being built in the USA and Canada for locomotives, factories and ships.
Diesel now became primarily a salesman for his engine, and he moved with family moved into a palatial mansion in Munich.
From there, he spent much of his time taking legal action to prevent patent applications, by other engineers seeking to improve on his engine.
This cost him a lot of time and nervous energy. It was mostly a waste of his effort, as he wasn’t usually successful. in court.
Overworked, stressed by patent trials, and pressurised by his family’s expensive lifestyle, Diesel got sick, and his fortune was gobbled up, without his knowledge.
When he became aware that his fortune was gone, it took it very badly. In 1913, Rudolf Diesel vanished from the ferry, the S.S. Dresden, as she sailed to England.
The date of his death is marked in his diary by a cross. Suggests Diesel chose to take his own life by suicide.
Diesel versus petrol
Diesel fuel is far less refined than petrol. It is a mixture of hydrocarbon molecules produced by the distillation of crude oil.
Petrol is far more explosive, and will light instantly when a match is put to it. Petrol is volatile even at room temperature and lets off fumes, and the vapour is flammable, so it is a dangerous fuel to have in an engine.
Diesel engines are based on a design where fuel is atomised and sprayed onto a compressed chamber of air, which results in small explosions.
This provides a lot of power potentially, but it is also means that the engine can be subject to shaking, and needs a hard body to contain it.
The petrol in petrol engines are ignited by spark plugs which light a fuel that has been highly refined and premixed before entering the engine.
The petrol engine, because it uses a more refined fuel, and because its ignition is less explosive, tend to be smoother running than diesel.
Both engines convert chemical energy present in the fuel into mechanical energy, which does useful work in driving the pistons up and down.
Diesel engines are better at converting more chemical energy into useful work, so they are said to be more efficient engines with less energy loss.
So, in most petrol engines, petrol and fuel are pre-mixed before being compressed. This was done in the ‘old days’ by a carburetor, but in cars today there is electronically controlled fuel injection.
In a diesel engine, the fuel is injected into very hot air, which has been compressed, at the end of a compression ‘stroke’ and self ignites.
Diesel is a thicker, heavier fuel than petrol, which works best in an engine going at a constant speed, and can solidify at low temperatures.
The world’s biggest and most powerful engines, like this one built for a supertanker, are invariably diesel engines (Source:
Why is the diesel so important ?
Diesel is crucial because it is the workhorse of industry. Diesel engines are reliable, powerful and safe, as they don’t use flammable fuel.
They are used everywhere, particularly where a lot of power is required such as trains, boats, lorries, submarines and tractors.
They are also used in cars, where they are touted to provide power, performance, as well as low emissions of pollutants.
No other engine still today is so versatile and is used in so many applications. The vast majority of the world’s commercial, industrial , agricultural, mining and military vehicles are diesel powered.
It is remarkable that a 19th century invention is still the most important engine in the world in the 21st century. Diesel engines power the world.
What kind of pollutants do diesel engines emit?
Diesel exhaust emissions contain toxic air contaminants some of which listed as cancer-causing.
Diesel cars, emit around 20 times more so called NOx (nitrogen oxide and nitrogen dioxide) as a result of their combustion design, than petrol engines, as well as small amounts carbon monoxides.
NOx is formed when nitrogen and oxygen from the air are combined – under heat and pressure. More heat and pressure gives you more NOx.
Diesel also contains sulphur, which can be hazardous to human health. Exposure to diesel particulate matter (or dpm, such as soot particles)
The US Environmental Protection Agency (EPA) says that even short term exposures to NO2, of 30 minutes, can result in airway inflammation in healthy people, and worse effects for those with asthma.
Exposure to NO2 linked with increased visits to A&E for respiratory issues. NO and NO2 are together often referred to as NOx and both are potentially harmful.
People living near roadways have been shown exposed to 30 to 100% higher concentrations of NO2 than those living away from roads, the US EPA says.
When nitric oxides are subject to heat and sunlight they react with volatile organic compounds to produce Ozone, which is also linked with all kinds of respiratory problems.
What did the ‘real world’ tests on VW diesels show up?
The hidden damage from these 11 million VW vehicles affected could equate to all of the UK’s NOx emissions from all power stations, vehicles, industry and agriculture.
The EPA tests have known practices and profiles. In many cases, the test vehicles are put on rollers and run at a certain speed for a certain time, then at another known speed for another known period.
The car’s central computer can detect whether inputs match those expected in test conditions.
A non governmental agency, the International Council on Clean Transportation (ICCT), performed independent – and crucially on-road – emissions tests, on the VW Passat, the VW Jetta, and a BMW X5.
The Jetta was found to be emitting up to 35 times the allowable limit of nitrogen oxide and the Passat up to 20 times.
These tests followed five routes on similar lines to the EPA simulations: highway, urban, suburban and rural up/downhill driving.
The emissions performance of the Volkswagen, but not the BMW, cars was so much worse than expectations that the ICCT ran further tests on a dynamometer.
In these circumstances, the cars passed with flying colours. It was at this point that the ICCT contacted the EPA.
The first diesel powered car was the 1936 Mercedes Benz 260D (Credit: Zoltan Glas)
How has the engine improved over the years?
Before World War 1, submarines were built with diesel engines, which were not as flammable and dangerous to the submariners.
After World War 1, where the diesel was widely used, the engine was adapted for an increasing number of peacetime usages.
The first big improvement was the move away from the cumbersome air blast injection system for diesels.The fact that a large compressor had to be attached to the engine prevented it being used in many situations.
Then in the 1920s, engineers developed. something called the Jerk type pump. This pump measured out a precise amount of fuel to be delivered as a spray to the engine at the precise moment it was required.
This fuel injection technology got rid of the need for an air compressor, and allowed for smaller, lighter diesels to be built and widely used.
Only on the roads, was the diesel engine slow to come in, and it was not until 1924, that MAN and Daimler Benz built the first diesel lorry.
It took even longer, until 1935, until the first diesel powered car appeared, the Mercedes Benz 260D.
The traditional design for the diesel engine was too noisy and heavy for road vehicles. However, in the late 20 century that engineers gave diesel cars better ‘road manners’.
Achieving this, however, was, it the expense of the environment. The more efficient combustion of diesel engines meant that the soot particles in diesel car exhausts became smaller and smaller, and more harmful to health since they could be inhaled more easily.
Engineers came up with a particle filter under the car, which collects and burns the soot particles. This type of filter is used in race cars and light aircraft.
The diesel became the engine of choice for military equipment on the ground and at sea during World War 11.
After the war, it was adapted for use in construction machinery, large tractors, most large trucks and buses.
Ultra-reliable diesel engines came into use in hospitals, telephone exchanges, and airports to provide power during power outages.
What happens if I put gasoline into a diesel engine?
Diesel in a gasoline engine will not even cause ‘firing’ because diesel is less volatile and will not mix with the air properly-sparking will not initiate combustion.
But, if you put gasoline in a diesel engine, you are putting a highly volatile fuel into a chamber of highly compressed and hot air.
This will lead to detonations, rather than smooth combustion, and eventually the engine components can get damaged!
Why is it so hard to develop clean diesel engines?
Diesel fuel is full of long hydrocarbon chains, and a gallon of diesel fuel contains more energy than a gallon of petrol.
The problem is that when diesel is burned in an uncontrollable way it is hard to control the waste products, which often include sulphur.
The old diesel cars, such as the 1979 Oldsmobile in the US spewed lots of tiny sulphur-containing particles into the air.
These days diesel car makers are good at trapping this kind of emission and the use of ultra-low sulphur diesel fuel helps.
However, it has proved more difficult for car makers to deal with the NOx gases, NO, NO2, and NO3.
These form at naturally at high temperatures, which are essential for a diesel engine to work. The react with sunlight and form ozone, which is O3.
Ozone is an irritant and bad for human health. It makes our yes water, our throat hurt, worsens asthma and causes heart problems too.
Diesel cars produce far more NOx than petrol cars.
The problem for engineers is that the temperatures and pressures under which a diesel engine runs best (in terms of pep and fuel efficiency) are also the conditions which will convert the maximum amount of oxygen and nitrogen into NOx.
With spontaneous ignition of diesel it’s not easy to keep track of what compounds have formed, and then to clean them up.
Also, it should be noted that in Europe, where about half of all cars run on diesel, there is less regulatory focus on NOx than greenhouse gases.
Does the Diesel engine have a future?
Many engineers believe the diesel has a bright future. It’s an engine that can run on peanut oil, and other biodiesels as Diesel himself showed.
There is no cheaper or more environmentally form of power today than combining a diesel engine with plant oil. If eco fuels catch on, it will be the final fulfillment of Rudolf Diesel’s dream.
William C Campbell, from Ramelton County Donegal became only the second Irish scientist to win a Nobel Prize recently for work on developing a drug against parasitic worms which have saved millions of lives (Credit: Nobel Media AB 2015)
The Martian is a thrilling film, which showcases the spectacular Martian landscape like no film before it, but how accurate is the science it depicts?
Up to 20 per cent of identical twins suffer from blood flow problems from their mother’s placenta. This can lead to brain damage, or death, but new surgery pioneered in Ireland at the Rotunda hospital is having twins’ lives.
Weight loss for many of us seemed a lot easier, back in the 1980’s. Now, scientists have come up with evidence to suggest that indeed it is harder to maintain a healthy weight today than it was a generation ago.
This item was first broadcast on East Coast FM on the 8th October 2015
Alan Turing is the mathematician credited with designing the principles for the world’s first computer, built during World War 2 to crack German codes. He’s also one of the founding philosophers of A.I. and more.
But did you know he was half Irish? He was by virtue of his mother, Ethel Stoney, who went to school in Dublin’s Alexandra College.
His parents – his father was Julius – had met on a trip back from India, and later got married in St Bartholomew’s Church in Ballsbridge.
Click HERE to listen to a discussion of Alan Turing, his life and achievements, as depicted in the film The Imitation Game, and the book upon which it was based Alan Turing: the enigma by Andrew Hodges.
The guests were myself, Sean Duke, science writer and broadcaster, Aoibhinn ní Shúilleabháin, mathematics educator at UCD and broadcaster, and Peter Arnds, comparative literature researcher at TCD.
