The Laser Interferometer Gravitational Wave Observatory is spearheading the completely new field of gravitational wave astronomy and opening a whole new window on the universe.
LIGO’s exquisitely sensitive instruments may ultimately take us farther back in time than we’ve ever been, catching, perhaps, the first murmurs of the universe in formation.
Astronomers clash with US air force over laser rules
* 22:29 13 October 2009 by David Shiga
Could astronomers accidentally blind Earth-observing satellites? That seems to be the worry of the US air force, which restricts the use of lasers pointed at the sky to help focus telescopes. But some astronomers warn they will miss key observations under the rules, which have tightened in recent years.
The laser causes a layer of sodium atoms at an altitude of about 90 kilometres to glow, producing an artificial star whose twinkles reveal the turbulence. Shape-shifting mirrors on the telescopes, called adaptive optics, then correct for the blurring by adjusting their shape many times per second.
If such a laser were to hit the optics of an Earth-observing satellite, it could cause damage. So the air force’s Space Command has for years restricted when and where US observatories can fire them, and the observatories have voluntarily complied, with little impact on astronomy.
Then about two years ago, just as kinks in the laser technology were being ironed out and interest in the lasers was growing, the rules were tightened. Now astronomers say the restrictions are beginning to chafe, according to a story first reported by the American Physical Society.
“Significant negative impacts of these new restrictions on scientific productivity are being felt,” says a 2008 report (pdf) by the US Association of Universities for Research in Astronomy, which is based in Washington, DC.
Poor Pluto. First it gets kicked out of the planet club, now it’s not even the coldest place in the solar system. Dark craters near the moon’s south pole have snatched that title – which is good news for the prospects of finding water ice on Earth’s companion.
The craters’ towering rims block the sun from reaching their centres, like the long shadows cast by tall buildings at dusk. In this permanent darkness, they stay at a constant -240 °Celsius – more than 30 °C above absolute zero and 10 °C cooler than Pluto, which was measured at -230 °C in 2006.
“The lunar south pole is among the coldest parts of the solar system and may be in fact colder than what we expect from places like Pluto,” NASA scientist Richard Vondrak said at a press conference on Thursday.
The cold temperature bodes well for the prospect of finding water ice deposits in the moon’s shadowy pockets. Previous calculations had shown that water and other volatile gases would dissipate into space at temperatures above about -220 °C.
The metallic green sheen of the jeweled beetle glitters only when certain types of light hit tiny structures on the shell of the insect. Otherwise, the green hue disappears, a new study finds.
While pigments account for the colors of flowers, leaves and other structures in nature, some organisms get their bright hues from the way light interacts with the microscopic structure of their skin, feathers or shells — for example, iridescent butterflies and certain sea creatures. …
As many as 40,000 ancient oaks and other species are to be inspected and appraised by the Trust, the most important organisation for ancient trees in the UK, in a three-year assessment of their condition.
There are so many because the Trust’s land holdings are enormous – they include more than 25,000 hectares of woodland, 200,000 hectares of farmland and 135 landscape and deer parks.
Isaac Newton’s apple tree at Woolsthorpe Manor in Lincolnshire has been regarded as a national treasure for more than 300 years. It is believed to have inspired Newton with the “notion of gravitation” in 1665, after he watched an apple fall to the ground.
Bearing a rare variety of apple, Flower of Kent, the tree fell over in 1820 but is still growing well.
The Magna Carta yew tree, at Runnymede in Berkshire, has been famous for even longer. It is 2,000 years old and now measures 9.4 metres (31ft) wide. Growing in the grounds of the ruined Priory of Ankerwycke, it is said to have witnessed the swearing and sealing of the Magna Carta, Britain’s first charter of freedom, by King John in June 1215. It is also said to be where Henry VIII met Anne Boleyn in the 1530s.
“Trees play such an important part in shaping our landscapes and reflecting our history that we need to make sure that the ancient trees in our care and the next generation to follow them can be enjoyed by everyone,” said Ray Hawes, the Trust’s head of forestry.
Researchers have confirmed that the sculptures on the triangular gables of the Parthenon temple in Athens were originally brightly painted.
Conservation scientists at the British Museum in London used a non-invasive technique to reveal invisible traces of an ancient pigment known as Egyptian blue. The team says that this is the first definitive evidence that the two-metre-high sculptures were not pristine white, as they appear today, but were precisely painted — as most sculptures from antiquity once were.
The belt of the winged messenger goddess Iris was painted blue, as shown by a luminescence technique (right). British Museum
The pigment, which was widely used until 800 AD, was identified on sculptures that formed parts of the decorated east and west ends of the Parthenon temple. Together with other parts of the temple, such as the frieze from within the building, they are sometimes collectively referred to as the Elgin marbles — removed by Lord Elgin, British ambassador to the Ottoman Empire from 1799–1803, and then transferred to the British Museum in 1816.
The scientists announced their findings just as the long-running feud over the ownership of the marbles has once again boiled over. The Acropolis Museum in Athens is due to be inaugurated on 20 June and was, in part, designed to house the marbles. Top delegates from the United Kingdom — including the Queen, Prime Minister Gordon Brown and Neil MacGregor, director of the British Museum — have declined to attend the opening.
The British Museum has also reiterated its standpoint on Greece’s request to repatriate the marbles, saying that it will not return any of them except on a short-term loan — and then only if Greece acknowledges the British Museum’s rightful ownership.
Antique paint
It has been known for more than two centuries that the Ancient Greeks and Romans painted their statues. That paint has almost completely disappeared over time, although tiny flecks can be found on most statues on close inspection. Unusually, no trace of paint has ever been found on the Parthenon sculptures, despite thorough analysis — including a full investigation by the renowned British physicist Michael Faraday in the 1830s.
There are more aspects of this issue. As can be read in this blog, in an earlier item on this:
In fact, in ancient Greece, people, including priests and priestesses, wore colourful clothes.
Their sculptures and buildings were colourful.
Similarly so in Etruscan and Roman cultures.
However, textiles rarely survived thousands of years.
While Greek buildings and statues sometimes did, but often with their colours hardly surviving.
So, in the eighteenth and nineteenth centuries an image arose in Western Europe and North America of ancient Greece as a land of people in ‘pure’ white clothes, with ’spotless’ white sculpture and buildings.
In that time, also racist ideologies evolved, intertwining ‘white race supremacy’ viewpoints with this misunderstanding of history.
At its sharpest in this was nazi Germany.
As seen in the aesthetics of the movie Olympia on the 1936 Berlin Olympic Games, made by Hitler’s favourite film director Leni Riefenstahl.
The Nature article continues:
Giovanni Verri, a physicist in the museum’s department of conservation and scientific research, developed a technique to exploit the fact that Egyptian blue emits near-infrared radiation when excited by visible light. His portable detector comprises a light-emitting diode that beams red light onto the surface being examined, and a camera that can detect the infrared light emitted by the pigment particles1.
The distribution of the pigment is also a key issue in proving that the sculptures were painted, says Verri. For example, the pigment found on the winged messenger goddess Iris traces just the belt restraining her billowing tunic (see picture, above), and nowhere else on the figure.
Greek conservators have recently observed greenish flecks on remnants of the Parthenon frieze that are in Athens, but have not reported analyses of them. “We informed our Greek colleagues of what we found,” says Verri, “and they responded warmly, saying they are interested to examine these flecks themselves.”
“I always believed the frieze must have been painted,” adds Ian Jenkins, senior curator in the British Museum’s Department of Greece and Rome. “This new method leaves no room for doubt.”
Verri thinks these frieze flecks could also be Egyptian blue, and is keen to examine them with his portable detector. But he adds that as diplomatic tensions have flared up again, now might be an insensitive time to offer.
Michael Shermer, publisher of Skeptic magazine and monthly columnist for Scientific American, tries his hand at firewalking barefoot across 1000-degree red hot coals and doesn’t get burned. Dr. Shermer provides a scientific explanation for the mysterious phenomenon.
(A shorter version of this appears as an op ed in the New York Times today)
Greed – and its crafty sibling, speculation – are the designated culprits for the ongoing financial crisis, but another, much admired, habit of mind should get its share of the blame: the delusional optimism of mainstream, all-American, positive thinking. As promoted by Oprah, scores of megachurch pastors, and an endless flow of self-help bestsellers, the idea is to firmly belief that you will get what you want, not only because it will make you feel better to do so, but because thinking things, “visualizing” them – ardently and with concentration – actually makes them happen. You will be able to pay that adjustable rate mortgage or, at the other end of the transaction, turn thousands of bad mortgages into giga-profits, the reasoning goes, if only you truly believe that you can.
Positive thinking is endemic to American culture – from weight loss programs to cancer support groups – and in the last two decades it put down deep roots in the corporate world as well. Everyone knows that you won’t get a job paying more than $15 an hour unless you’re a “positive person” — doubt-free, uncritical, and smiling—and no one becomes a CEO by issuing warnings of possible disaster. According to a rare skeptic, a Washington-based crisis management consultant I interviewed on the eve of the credit meltdown in 2007, even the magical idea that you can have whatever you truly want has been “viral” in the business culture. All the tomes in airport bookstores’ business sections scream out against “negativity” and advise the reader to be at all times upbeat, optimistic and brimming with confidence—a message companies relentlessly reinforced by treating their white collar employees to manic motivational speakers and revival-like motivational events. The top guys, meanwhile, would go off to get pumped up in exotic locales with the likes of success guru Tony Robbins. Those who still failed to get with the program could be subjected to personal “coaching” or of course, shown to the door.
The same frothy wave of mandatory optimism swept through the once-sober finance industry. On their websites, scores of motivational speakers proudly list companies like Lehman Brothers and Merrill Lynch among their clients.
The first beam of subatomic particles in the world’s newest and largest particle collider went around the full 27 kilometres (17 miles) of the machine’s length this morning, scientists announced.
“This historic event marks a key moment in the transition from over two decades of preparation to a new era of scientific discovery,” said an announcement from CERN, the European Organization for Nuclear Research based in Geneva.
“We can now look forward to a new era of understanding about the origins and evolution of the universe,” said Lyn Evans, project leader for the particle smasher, known as the Large Hadron Collider.
Colliders, also known as accelerators, are designed to crash subatomic particles together to find out what lies within them.
A new technique allows pictures which were later painted over to be revealed once more. An international research team, including members from Delft University of Technology (The Netherlands) and the University of Antwerp (Belgium), has successfully applied this technique for the first time to the painting entitled Patch of Grass by Vincent van Gogh. Behind this painting is a portrait of a woman.
A new technique, based on synchrotron radiation induced X-ray fluorescence spectroscopy, reveals this type of hidden painting. …
This method was applied to a painting by Vincent van Gogh. The work in question, Patch of Grass, was painted by Van Gogh in Paris in 1887 and is owned by the Kröller-Müller Museum. Previous research had already discovered the vague outline of a head behind the painting. It was scanned at the synchrotron radiation source DORIS at Deutsches Elektronen-Synchrotron DESY in Hamburg using an intense but very small X-ray bundle. Over the course of two days, the area covering the image of a woman’s head was scanned, measuring 17.5 x 17.5 cm.
The measurements enabled researchers to reconstruct the concealed painting in unparalleled detail. In particular the combination of the distribution of the elements mercury and antimony (from specific paint pigments) provided a ‘colour photo’ of the portrait which had been painted over.
The reconstruction enables art historians to understand the evolution of Van Gogh’s work better. The applied technique is expected to pave the way for research into many other concealed paintings.
* 25 June 2008
* Rob Edwards
* Magazine issue 2662
YOU might think nuclear weapons have been carefully designed not to go off by accident. Yet more than 1700 of them have design flaws that could conceivably cause multiple warheads to explode one after another - an effect known as “popcorning” - according to a UK Ministry of Defence safety manual.
A typical Trident nuclear missile contains from three to six warheads, and a US submarine might carry up to 24 missiles. Weapons builders aim to prevent accidental explosions of warheads by designing them to be “single-point safe”. This means that a sudden knock at a single point - say if it were dropped from a crane while being unloaded from a submarine - should not detonate the plutonium core.
However, a nuclear-weapons safety manual drawn up by the MoD’s internal nuclear-weapons regulator argues that this standard single-point design might not be enough to prevent popcorning.
The belt of the winged messenger goddess 
