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Solar System to Scale
The European Space Agency has tried hard to avoid using the words “crash” or “failure” about its attempted Mars landing but the fate of the spacecraft is cruelly exposed in new pictures. Source: BBC News
Thanks to Phil Krause for suggesting this post
John R. “Jack” Horner (born June 15, 1946) is a non-degree holding American paleontologist who discovered and named Maiasaura, providing the first clear evidence that some dinosaurs cared for their young. He is one of the best-known paleontologists in the World. In addition to his many paleontological discoveries, Horner served as the technical advisor for all of the Jurassic Park films, had a cameo appearance in Jurassic World, and even served as partial inspiration for one of the lead characters, Dr. Alan Grant. He studied at the University of Montana and was awarded a Doctorate in Science honoris causa. He married Vanessa Shiann Weaver in January 2012.
Horner was born and raised in Shelby, Montana. He was only eight years old when he found his very first dinosaur bone. He attended the University of Montana for seven years, majoring in geology and zoology. He also spent two years in the U.S. Marine Corps, serving during the Vietnam War in the Special Forces. Horner did not complete his bachelor’s degree due to severe dyslexia. However, he did complete a formidable senior thesis on the fauna of the Bear Gulch Limestone in Montana, which is one of the most famous Mississippian lagerstätten (or exceptionally preserved fossil site) in the world. The University of Montana awarded him an Honorary Doctorate of Science in 1986. In 1986, he was also awarded the prestigious MacArthur Fellowship.
In Montana during the mid-1970s, Horner and his research partner Bob Makela discovered a colonial nesting site of a new dinosaur genus which they named Maiasaura, or “Good Mother Lizard”. It contained the first dinosaur eggs in the Western hemisphere, the first dinosaur embryos, and settled questions of whether some dinosaurs were sociable, built nests and cared for their young. The discovery established his career. Horner has named several other species of dinosaur (including Orodromeus makelai in memory of his late friend Bob Makela) and has had two named after him: Achelousaurus horneri and Anasazisaurus horneri. Continue reading
Five years ago, the Nobel Prize in Physics was awarded to three astronomers for their discovery, in the late 1990s, that the universe is expanding at an accelerating pace. Their conclusions were based on analysis of Type Ia supernovae – the spectacular thermonuclear explosion of dying stars – picked up by the Hubble space telescope and large ground-based telescopes. It led to the widespread acceptance of the idea that the universe is dominated by a mysterious substance named ‘dark energy’ that drives this accelerating expansion.
Now, a team of scientists led by Professor Subir Sarkar of Oxford University’s Department of Physics has cast doubt on this standard cosmological concept. Making use of a vastly increased data set – a catalogue of 740 Type Ia supernovae, more than ten times the original sample size – the researchers have found that the evidence for acceleration may be flimsier than previously thought, with the data being consistent with a constant rate of expansion.
The study is published in the Nature journal Scientific Reports.Professor Sarkar, who also holds a position at the Niels Bohr Institute in Copenhagen, said: ‘The discovery of the accelerating expansion of the universe won the Nobel Prize, the Gruber Cosmology Prize, and the Breakthrough Prize in Fundamental Physics. It led to the widespread acceptance of the idea that the universe is dominated by “dark energy” that behaves like a cosmological constant – this is now the “standard model” of cosmology.’ However, there now exists a much bigger database of supernovae on which to perform rigorous and detailed statistical analyses. We analysed the latest catalogue of 740 Type Ia supernovae – over ten times bigger than the original samples on which the discovery claim was based – and found that the evidence for accelerated expansion is, at most, what physicists call “3 sigma”. This is far short of the “5 sigma” standard required to claim a discovery of fundamental significance.
‘An analogous example in this context would be the recent suggestion for a new particle weighing 750 GeV based on data from the Large Hadron Collider at CERN. It initially had even higher significance – 3.9 and 3.4 sigma in December last year – and stimulated over 500 theoretical papers. However, it was announced in August that new data shows that the significance has dropped to less than 1 sigma. It was just a statistical fluctuation, and there is no such particle.’
There is other data available that appears to support the idea of an accelerating universe, such as information on the cosmic microwave background – the faint afterglow of the Big Bang – from the Planck satellite. However, Professor Sarkar said: ‘All of these tests are indirect, carried out in the framework of an assumed model, and the cosmic microwave background is not directly affected by dark energy. Actually, there is indeed a subtle effect, the late-integrated Sachs-Wolfe effect, but this has not been convincingly detected.’
So it is quite possible that we are being misled and that the apparent manifestation of dark energy is a consequence of analysing the data in an oversimplified theoretical model – one that was in fact constructed in the 1930s, long before there was any real data. A more sophisticated theoretical framework accounting for the observation that the universe is not exactly homogeneous and that its matter content may not behave as an ideal gas – two key assumptions of standard cosmology – may well be able to account for all observations without requiring dark energy. Indeed, vacuum energy is something of which we have absolutely no understanding in fundamental theory.’ Source: The universe is expanding at an accelerating rate—or is it?
Stefanie Tompkins, a geologist and director of DARPA’s Defense Sciences Office, envisions building substances from the atomic or molecular level up to create “impossible” materials with previously unattainable capabilities.
Europe’s Schiaparelli lander did not behave as expected as it headed down to the surface of Mars on Wednesday. Telemetry data recovered from the probe during its descent indicates that its parachute was jettisoned too early. The rockets it was supposed to use to bring itself to a standstill just above the ground also appeared to fire for too short a time.
The European Space Agency (Esa) has not yet conceded that the lander crashed but the mood is not positive. Experts will continue to analyse the data and they may also try to call out to Schiaparelli in the blind hope that it is actually sitting on the Red Planet intact. In addition, the Americans will use one of their satellites at Mars to image the targeted landing zone to see if they can detect any hardware. Although, the chances are slim because the probe is small.
For the moment, all Esa has to work with is the relatively large volume of engineering data Schiaparelli managed to transmit back to the “mothership” that dropped it off at Mars – the Trace Gas Orbiter. This shows that everything was fine as the probe entered the atmosphere. Its heatshield appeared to do the job of slowing the craft, and the parachute opened as expected to further decelerate the robot. But it is at the end of the parachute phase that the data indicates unusual behaviour.
“We cannot resolve yet under which, let’s say, logic that the machine has decided to eject the parachute. But this is definitely far too early compared to our expectations,” Andrea Accomazzo, the head of operations for Esa’s planetary missions, told BBC News.
Visualisation of the ExoMars Schiaparelli module entering and descending through the martian atmosphere to land on Mars.
Schiaparelli will enter the atmosphere at about 21 000 km/h and in less than six minutes it will use a heatshield, a parachute and thrusters to slow its descent before touching down in the Meridiani Planum region close to the equator, absorbing the final contact with a crushable structure.
The entire process will take less than six minutes: the animation has been sped up.
Schiaparelli is set to separate from the Trace Gas Orbiter on 16 October, after a seven-month cruise together through space, and will enter the atmosphere on 19 October at 14:42 GMT.
For an overview of the key timings and altitudes corresponding to the events portrayed in this animation see the Schiaparelli descent sequence graphic
Everyone knows what happened 950 years ago this month, don’t they? William the Conqueror killed Harold and became King of England.
Not quite. Harold and the flower of his army died at Hastings on 14 October 1066. But the magnates of England then proclaimed Edgar the Aetheling as King.
Edgar the who? “A forgotten prince… but one of the builders of a new England” is how the historical novelist Stewart Binns describes him.
John Speed in his History of Great Britaine (1611) said Edgar was “In such esteem with the people, that he was called England’s darling.”
The English leaders then turned to the 14-year-old Edgar.He “came close to winning back his throne and reversing the Norman Conquest… He deserves to be better remembered,” says Martin Lake, who has written four novels centred on him. But for most he really is a forgotten prince (Aetheling in Anglo-Saxon means prince).
While England forgot him, Scotland took his sister Margaret to its heart. As Queen she is credited with important reforms; as a saint her works of charity and the miracles of her shrine were recorded in great detail – some of them legendary, perhaps.
But where is Edgar’s legend? There are many remarkable stories about him. That he led a party of knights errant into Italy – that he was showered with gifts by the Byzantine emperor, allegedly including an elephant. Legends have been built on less. For a historian the stories need “ifs” and “abouts” and “perhapses” but for a legend they are fine.
Read the whole story here: ‘England’s darling’ and Scotland’s saint
In research published in Science, a Stanford-led international team used a new analytic technique to map recent evolution. The technique relies exclusively on the DNA sequences of modern humans, yet it can reveal rapid changes in the prevalence of different gene variants over the last 2,000 to 3,000 years.
The team was motivated to understand how natural selection works in humans and was able to draw on the genomes of 3,195 Britons stored in a database of 10,000 UK genomes, said the paper’s senior author, Stanford geneticist and biologist Jonathan Pritchard, PhD. The lead author was Yair Field, PhD, a postdoctoral scholar in Pritchard’s lab. Previous approaches lacked the resolution to look at periods of time less than 10,000 to 20,000 years, Pritchard said. But their approach could recognize very recent and very strong selection, he said. “Our work shows that selection has continued until very recently, probably within the past 500 years or so,” said Pritchard.
Tracking changes in the population wide frequencies of different versions, or alleles, of a gene allows researchers to watch microevolution in action. They found several cases of rapid evolution, including the gene that regulates whether we make the enzyme lactase, which allows us to digest milk sugars, which is one of the best understood examples of this small-scale evolutionary change.Infants make lots of lactase so they can digest milk. Most mammals turn off the lactase gene after weaning. Once lactase is turned off in adults, if they drink milk, they get a stomach ache and diarrhea. But in some human populations, up to 80 percent of people carry a mutation that allows them to continue making lactase and drink milk as adults. Populations with a high prevalence of the lactase-persistence gene are more likely to raise animals that produce milk, such as cows and goats.
Since dairy farming is only a few thousand years old, it was no surprise that the lactase-persistence gene has become more prevalent, evolving rapidly and recently among the Britons, the study found.Most traits, however, are influenced not by one or two genes but by hundreds that are scattered across our 23 pairs of chromosomes. For example, nearly 700 genes are known to influence height in humans. And northern Europeans are known to possess more height-promoting alleles than southern Europeans.The current study concluded that in the last 2,000 to 3,000 years, natural selection has caused an increase in the prevalence of 551 gene alleles associated with being taller among the Britons in the sample.
What selective forces might cause the changes is still unknown. For natural selection to occur, individuals with the selected traits would have to consistently have more children over the 2,000-year period of the study.I asked Pritchard how he knows that the changes in allele frequency are due to natural selection rather than chance. He said that although the genome is constantly changing, the new technique allows researchers to pick out alleles whose frequency is changing faster than that of other alleles.
“If most of the genome is not under strong selection, it’s all kind of drifting along at the same rate. The amount of drift is the same,” he said. “So if you see something different—like a change in frequency that’s 10 times or 100 times than what you’d expect from drift—then it’s much more likely that what your seeing it due to natural selection.” Source: New technique offers glimpse at human evolution in action
Thanks to Alan Mason for this new post. Be sure to check out Alan’s other posts here.This is one of the most famous paintings of the nineteenth century French Impressionist movement, and I regard it as an old friend. In the early 1960s, I was a student in the Bloomsbury district of London. In those days, the Courtauld Institute, and its own Gallery, was on the northern edge of Bloomsbury. I went to the Courtauld Gallery about every couple of weeks, and I could see “A Bar at the Folies Bergeres”, as well as many other works.
Typically, I would have my lunch in one of several modestly-priced institutional restaurants, like the Senate House tower (2), Birkbeck College, or The London School of Hygiene and Tropical Medicine. After lunch, a five minute walk took me to the Courtauld, where I could sit in comfortable armchairs and sofas to contemplate the artworks, during the rest of my break.
The gallery was not well-known to tourists and consequently was always very quiet. It was reached by a lift to the fourth floor, and there was always a secret feel about it; a hidden gem. All has changed now. In 1989 the Gallery, and Courtauld Institute were transferred to a much grander site,-Somerset House (3), a magnificent monumental conception, begun in 1775 by the architect, William Chambers.
It was designed to unite a number of government offices in one site. It has had a chequered history, because of a changing set of uses over the last 250 years. It was, for a time, the registry for births, marriages and deaths, and this designation has clung to the buildings, in popular parlance, despite any evidence to the contrary. The last time I visited it, was to consult its records of wills. Perhaps the presence of the Courtauld collection (4) will give the buildings a final and fitting function.
The new Gallery has plenty of room to hold a barn dance, or even a grand ball, but it lacks the quiet intimacy of the old gallery, with its blue furnishings. Sharp-eyed readers may detect Manet’s other famous masterpiece, “Le Dejeuner sur L’Herbe”, (“Lunch on the Grass”) on the right, and Cèzanne’s “Mont St Victoire” over on the extreme left.
The Folies Bergère
In the Britain of the 1940s and 1950s the phrase, “Folies Bergère” was a byword for female nude entertainment, mainly because few people had ever taken holidays abroad, or visited Paris. In reality, the Folies Bergère was what the English called a “music-hall”. It featured singers, comedians, trapeze acts, and magicians, as well as dancers and nude acts. The mirror, behind the barmaid, shows a trapeze (5), and the feet of the performer. A poster from the 19C promises scantily clad dancers (6).
The name of this French music-hall remains untranslated, like many idiomatic French phrases, mainly because the English translations just sound absurd. “Folies Bergère” literally means, “The Silly Shepherdess”. It opened in 1869 as the “Folies Trèvise” but changed its name three years later to “The Folies Bergère”, after a nearby street, the rue Bergère. (Ref B)
A driverless car has been tested among members of the public for the first time in the UK, in Milton Keynes. The two-seater electric vehicle travelled in a 1km (0.6-mile) loop on the pavements around the town’s railway station.
The team behind it hopes a fleet of 40 of the pods will be available to the public next year.It called the test “a landmark step” towards bringing self-driving vehicles to the roads of the UK. Local dignitaries and members of the press sat alongside a safety driver, who was there to take the car out of autonomous mode in the case of an emergency.
Programme director Neil Fulton said: “This public demonstration represents a major milestone for autonomous vehicles in the UK and the culmination of an extensive project involving UK companies and experts. Source: BBC News
Sunshine and seawater. That’s all a new, futuristic-looking greenhouse needs to produce 17,000 tonnes of tomatoes per year in the South Australian desert. It’s the first agricultural system of its kind in the world and uses no soil, pesticides, fossil fuels or groundwater. As the demand for fresh water and energy continues to rise, this might be the face of farming in the future. An international team of scientists have spent the last six years fine-tuning the design
More here: New Scientist
A simple, interactive living space in total harmony with the surrounding space – here Panasonic showcases its proposal to the details of living. Changing the spatial ambience to suit human behavior makes people feel comfortable no matter where they go and even give a surprisingly wondrous feeling.
The Scanning Transmission Electron Holography Microscope stands 15 feet tall and weighs 14,000 pounds. “It’s such a powerful machine,” says Rodney Herring, who runs the microscope facility at the University of Victoria in Canada. It can image at an unprocessed resolution of 35 trillionths of a meter, making it more powerful than any other microscope in the world.And any telescope too.
Microscopes like Herring’s take images using electrons, which have a wavelength five orders of magnitude smaller than that of light. Telescopes can’t use the same approach, because electrons from a far-off source would be deflected or absorbed before they made their way to Earth.
“Electrons don’t reach us, but light does,” says Herring, which is one reason that “we can see a lot better looking down at small things than we can looking out at big things.”
Microscopists can also manipulate their samples. According to Mark Neil, an optical physicist at Imperial College London, illuminating a sample with a pair of lasers can improve the resolution of a normal microscope, from 300 nanometers to 10 nm. Electron microscopes like Herring’s push that down even farther, into the atomic scale.It’s hard to find a comparable measure for a giant telescope. Astronomers are less concerned with linear resolution than they are with angular resolution, measured in arc-seconds (1/3,600 of a degree). The Hubble Space Telescope, for example, can take images less than 0.1 arc-seconds. The European Extremely Large Telescope—currently under construction on a Chilean mountaintop—will have an angular resolution of 0.01 arc-seconds or better.
To draw an accurate comparison between telescopes and microscopes, we should think of them in terms of the unaided human eye. Neil says a person with normal vision is able to perceive objects at a linear resolution of about 25,000 nm and an angular resolution of about 60 arc-seconds.So the best microscopes take us from 25,000 nm to 0.035 nm—a 714,000-fold improvement. The best telescopes, on the other hand, can push our vision only from 60 arc-seconds to 0.01 arc-seconds—a 6,000-fold improvement. Source: Which is More Powerful: A Giant Microscope or a Giant Telescope?
Deskarati is always alert to anniversaries, and I want to share some thoughts on an event that I wish had never happened. On the 21 Oct 1966, during a period of wet weather, a colliery waste heap of black mud and rocks, slid down the hillside, and engulfed the Pantglas Junior School in Aberfan, South Wales, killing 116 children and 28 adults. This was what civil engineers call a “quick clay slide”, where what was stable and semi-solid becomes semi-liquid and unstable, if enough water is added.
At the time I was working in a junior school in London, and all the teachers were stunned by the news. What if this had been our school? Suppose that it was our children who had been choked to death in a flood of filthy black mud? Three of my young women colleagues were from the valleys of South Wales, and took the news very badly. One of them came from the small town of Mountain Ash, in the next valley to Aberfan (this is a Welsh spelling and is always pronounced “aber –van”). How on earth could such a thing have happened?
Following the end of the Second World War, the privately-owned coal mines were broke, and many were likely to go bankrupt soon. Then the Labour government, under Clement Attlee, (2) nationalised the mines in 1948. Miners were always going to be in demand, because in 1948 coal was vital to everyday life. Most power stations burned coal; most offices and factories were heated by coal-fired boilers; most homes were heated by coal fires, and the railways used coal-burning locomotives; it was a very different world from that of today.
ESA’s historic Rosetta mission has concluded as planned, with the controlled impact onto the comet it had been investigating for more than two years. Confirmation of the end of the mission arrived at ESA’s control centre in Darmstadt, Germany at 11:19 GMT (13:19 CEST) with the loss of Rosetta’s signal upon impact.
Rosetta carried out its final manoeuvre last night at 20:50 GMT (22:50 CEST), setting it on a collision course with the comet from an altitude of about 19 km. Rosetta had targeted a region on the small lobe of Comet 67P/Churyumov–Gerasimenko, close to a region of active pits in the Ma’at region.
The descent gave Rosetta the opportunity to study the comet’s gas, dust and plasma environment very close to its surface, as well as take very high-resolution images. Pits are of particular interest because they play an important role in the comet’s activity. They also provide a unique window into its internal building blocks.
The information collected on the descent to this fascinating region was returned to Earth before the impact. It is now no longer possible to communicate with the spacecraft.
“Rosetta has entered the history books once again,” says Johann-Dietrich Wörner, ESA’s Director General. “Today we celebrate the success of a game-changing mission, one that has surpassed all our dreams and expectations, and one that continues ESA’s legacy of ‘firsts’ at comets.”
“Thanks to a huge international, decades-long endeavour, we have achieved our mission to take a world-class science laboratory to a comet to study its evolution over time, something that no other comet-chasing mission has attempted,” notes Alvaro Giménez, ESA’s Director of Science.
“Rosetta was on the drawing board even before ESA’s first deep-space mission, Giotto, had taken the first image of a comet nucleus as it flew past Halley in 1986.“
The mission has spanned entire careers, and the data returned will keep generations of scientist busy for decades to come.” Source: Mission complete: Rosetta’s journey ends in daring descent to comet
One of the most audacious space missions ever undertaken is about to come to an end. The Rosetta probe that has been tracking a comet for the past two years is going to deliberately crash itself into the 4km-wide ball of ice and dust.
European Space Agency scientists say the satellite has come to the end of its useful life and they want to get some final, ultra-close measurements. Rosetta is not expected to survive the impact with Comet 67P. But even if some of its systems remain functional, pre-loaded software on board will ensure everything is shut down on contact.
Controllers here at Esa’s operations centre in Darmstadt, Germany, will command Rosetta to change course late on Thursday.
The manoeuvre will alter its wide orbit around the duck-shaped icy wanderer and put it on a direct collision course. The probe should hit the comet’s “head” at roughly walking pace at about 11:20 GMT (12:20 BST/1320 CEST) on Friday.
The crash velocity will be low, less than a metre per second, but Rosetta was never designed to land and so various components will almost certainly be crushed as it dumps down. “Just to give you an example, if the high-gain antenna is off-pointing by more than half a degree then there is no communication possible anymore,” said Esa spacecraft operations manager Sylvain Lodiot. Source: Rosetta probe heads for comet crash