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The Declaration of White Independence: Fourth Political Theory

A unilateral assertion offered to and for consideration by the European Descended People of the fifty united States of America and all ...

31 July 2013

Viewpoint: The Seeds of a Magnetic Universe

The Universe is magnetized. This is true on “small” length scales, such as in planets and stars, and over much larger scales, such as across the tenuous gas in galaxies and galaxy clusters and, possibly, the even more rarefied intergalactic medium. Physicists are fairly certain that these magnetic fields weren’t created in the big bang (the reason has to do with the symmetry of Maxwell’s equations). Rather, for the most part, they assume that small “seed fields,” which formed some time after the big bang, were amplified into what we observe today. But how these seed fields materialized remains one of the great, unsolved problems in cosmology.

In Physical Review Letters, Smadar Naoz and Ramesh Narayan at the Harvard-Smithsonian Center for Astrophysics, Massachusetts, propose a possible solution. They have revisited a model for the generation of small magnetic fields in a plasma, called the Biermann battery, and shown that this process could have generated seed fields in the Universe much earlier than was previously thought possible. Although the fields they calculate are weak, the fact that they could have existed early in the age of the Universe means there was more time for other processes to amplify them into the fields we observe today.

Theories of the origin of cosmological fields, or, magnetogenesis, are either top down or bottom up. Top down theories invoke a process that operates everywhere, producing a pervasive field. In bottom up theories, magnetogenesis occurs in small objects, and the magnetic fields are then dispersed to large scales. Both types of theory require two stages. The first is to create a seed field. In the second phase, the existing field grows by a process called a dynamo, in which the kinetic energy in the flowing magnetic plasma is converted, by induction, into magnetic energy. (The 22-year solar magnetic activity cycle is a famous example of an astrophysical dynamo.) Although it’s still unclear exactly how plasma flows amplify magnetic fields, large-scale shear and small-scale turbulence are both thought to play a role.

Thomas Nagel: Thoughts Are Real

 
The philosopher Thomas Nagel’s new book, “Mind and Cosmos: Why the Materialist Neo-Darwinian Conception of Nature Is Almost Certainly False,” restores the primal force of a great old philosophical word, “metaphysics.” He starts with a boldly discerning look at that strange creature, mankind, and comes to some remarkable speculations about who we are and what our place is in the universe. Incidentally (and seemingly unintentionally) he illuminates, along the way, some significant aspects of the cinema, and of art overall. 
 
The book deals with science—specifically, Darwinian ideas regarding evolution and natural selection—and it’s filled with the quasi-scientific language and argumentation that characterizes much of Anglo-American analytical philosophy. This is unfortunate, because the ideas that Nagel unfolds ought to be discussed by non-specialists with an interest in the arts, politics, and—quite literally, in this context—the humanities.
 
Physics is the question of what matter is. Metaphysics is the question of what exists. People of a rational, scientific bent tend to think that the two are coextensive—that everything is physical. Many who think differently are inspired by religion to posit the existence of God and souls; Nagel affirms that he’s an atheist, but he also asserts that there’s an entirely different realm of non-physical stuff that exists—namely, mental stuff. The vast flow of perceptions, ideas, and emotions that arise in each human mind is something that, in his view, actually exists as something other than merely the electrical firings in the brain that gives rise to them—and exists as surely as a brain, a chair, an atom, or a gamma ray.
 
In other words, even if it were possible to map out the exact pattern of brain waves that give rise to a person’s momentary complex of awareness, that mapping would only explain the physical correlate of these experiences, but it wouldn’t be them. A person doesn’t experience patterns, and her experiences are as irreducibly real as her brain waves are, and different from them.
 
Nagel offers mental activity as a special realm of being and life as a special condition—in the same way that biology is a special realm of science, distinct from physics. His argument is that, if the mental things arising from the minds of living things are a distinct realm of existence, then strictly physical theories about the origins of life, such as Darwinian theory, cannot be entirely correct. Life cannot have arisen solely from a primordial chemical reaction, and the process of natural selection cannot account for the creation of the realm of mind. Biology, in his view, becomes a variety of science that is radically distinct from physics—it deals with a vast and crucial realm of phenomena that physics doesn’t and can’t encompass, precisely because they’re aspects of living things that are not physical:
 
subjective consciousness, if it is not reducible to something physical, … would be left completely unexplained by physical evolution—even if the physical evolution of such organisms is in fact a causally necessary and sufficient condition for consciousness.

Since neither physics nor Darwinian biology—the concept of evolution—can account for the emergence of a mental world from a physical one, Nagel contends that the mental side of existence must somehow have been present in creation from the very start. But then he goes further, into strange and visionary territory. He argues that the faculty of reason is different from perception and, in effect, prior to it—“an irreducible faculty.” He suggests that any theory of the universe, any comprehensive mesh of physics and biology, will need to succeed in “showing how the natural order is disposed to generate beings capable of comprehending it.”
 
And this, he argues, would be a theory of teleology—a preprogrammed or built-in tendency in the universe toward the particular goal of fulfilling the possibilities of mentality. In a splendid image, Nagel writes, “Each of our lives is a part of the lengthy process of the universe gradually waking up and becoming aware of itself.”
 
In effect, the universe tends toward maximizing certain goals and places “value in the result toward which things tend”—and Nagel assimilates this metaphysical tendency to human morality, which would mesh, gradually and incrementally (with backward as well as forward steps) with the value that inheres in the universe. In this view, the discovery of those values is inextricable from the understanding of what the universe is. Physics and metaphysics, biology and moral philosophy join together in Nagel’s vision of a distant, eventually unified-field theory of the universe, of existence.
 
His cosmic, overarching vision is remarkably anthropocentric—anchored in an idea of practical progress at a scale of human experience, with human history echoing the history of the universe.
I’m immensely sympathetic to Nagel’s line of thought (full disclosure: he was my professor for a semester at Princeton in the mid-seventies). It offers, in a vastly more substantial form, a parallel to my own view of movies. When discussion arose here several years ago regarding new trends toward realistic movie-making, I contended, in effect, that everything is real—that the realities that matter in movies are mental constructs, whether emotional or political, and that, therefore, a movie that rigorously represents solely the physical aspects and actions of its characters doesn’t necessarily come any closer to anything like reality, and may even get further from it.
 
A work of animation, a C.G.I. fantasy, or a film that depicts its characters’ dreams, visions, hallucinations, and inner voices—or that fragments events with montage of images and sounds—may well get to reality more intimately, deeply, or fully. The recent movie that seems best to embody a perspective similar to Nagel’s is Terrence Malick’s “The Tree of Life,” with its view of a kind of prehistorical history as related to lived (albeit imagined) experience. (The most famous example is the remarkable scene of C.G.I.-generated dinosaurs discovering a primordial sense of mercy.)
 
Nagel’s thesis has, I think, similarly radical consequences for philosophy itself. His argument implies that consciousness—indeed, mental life, whether conscious or not—is not atomic but holistic: there is no such thing as a piece or an atom of experience, but, rather, a mind at a given moment is flooded with an incalculable number of perceptions, memories, ideas, judgments, and desires. Even enumerating them in the plural is a little silly, because it implies the ability to isolate them as singular events or things. Therefore, philosophy, in order to account for mental life, will need to turn aside from isolated experiments in logic and argumentation in favor of rough-edged, life-sized chunks—historical events and figures, works of art, artists themselves, cities, countries, languages, human dramas of all sorts, lived or imagined.
 
Which is to say that, though Nagel doesn’t write about art in “Mind and Cosmos,” the book’s widest implications involve art and how it helps us to understand the world. If Nagel is right, art itself would no longer be merely the scientist’s leisure-time fulfillment but would be (I think, correctly) recognized as a primary mode of coming to grips with the mental and moral essence of the universe. It would be a key source of the very definition of life. Aesthetics will be propelled to the forefront of philosophy as a crucial part of metaphysical biology, and so, the writing and practice of philosophy will come to look more like texts by Nietzsche, with their own built-in aesthetic and subjective components and emphases on historical and practical events. The very beauty of Nagel’s theory—its power to inspire imagination—counts in its favor.

Incredible Technology: How to See the Big Bang

While we may never know all the details of our universe's explosive birth, scientists have been able to piece together quite a bit by studying the ancient light that saturates the cosmos.
The universe burst into existence 13.8 billion years ago in a "Big Bang" that blew space up like a giant balloon. For nearly 400,000 years after that, the universe remained a seething-hot, opaque fog of plasma and energy.

But then, in an epoch known as recombination, the temperature dropped enough to allow the formation of electrically neutral atoms, turning the universe transparent. Photons began to travel freely, and the light we know as the cosmic microwave background (CMB) pervaded the heavens, filled with clues about the first few moments after creation. [Big Bang to Now in 10 Easy Steps]

"As far as we know, that's as far [back] as we can see — we get an image of the universe as it was when it was about 389,000 years old," said John Mather of NASA's Goddard Space Flight Center in Greenbelt, Md., senior project scientist for the space agency's James Webb Space Telescope, the successor to the Hubble Space Telescope. Mather and George Smoot won the 2006 Nobel Prize in Physics for their work on NASA's Cosmic Background Explorer satellite mission.

"We believe — although it's not 100 percent proven — that spots that we see in the microwave map from when the universe was 389,000 years old were actually imposed on it when [the universe] was sub-microseconds old," Mather told SPACE.com. "There's an interpretive step there, but it's probably right."

"We believe — although it's not 100 percent proven — that spots that we see in the microwave map from when the universe was 389,000 years old were actually imposed on it when [the universe] was sub-microseconds old," Mather told SPACE.com. "There's an interpretive step there, but it's probably right."

Most researchers think the "bang" portion of the Big Bang came during a dramatic and extremely brief period of inflation, which began about 10 to the minus 36 seconds — one trillionth of a trillionth of a trillionth of a second — after the universe's birth.

During inflation, the theory goes, the universe expanded faster than the speed of light, doubling in size perhaps 100 times or more in just a few tiny fractions of a second. (Einstein's theory of special relativity holds that no information or matter can travel faster than light through space, but this rule does not apply to inflation, which was an expansion of space itself.)

"Inflation theory is the idea of going from spontaneous quantum fluctuations to something of macroscopic size," said WMAP principal investigator Charles Bennett, of Johns Hopkins University in Baltimore, Md. (The WMAP spacecraft, which launched in 2001, stopped gathering data in 2010.)
The precision mapping of the CMB performed by COBE, WMAP and Planck has provided strong support for inflation, helping cement its position as the leading explanation of the universe's first few moments.

"Why the cosmic microwave background temperature is the same at different spots in the sky would be a mystery if it was not for inflation saying, well, our whole sky came from this tiny region," Bennett told SPACE.com. "So the idea of inflation helps answer some of these mysteries, and it explains where these fluctuations came from."http://news.yahoo.com/incredible-technology-see-big-bang-153127374.html

25 July 2013

Light stopped completely for a minute inside a crystal: The basis of quantum memory

Scientists at the University of Darmstadt in Germany have stopped light for one minute. For one whole minute, light, which is usually the fastest thing in the known universe and travels at 300 million meters per second, was stopped dead still inside a crystal.
This effectively creates light memory, where the image being carried by the light is stored in crystals. Beyond being utterly cool, this breakthrough could lead to the creation of long-range quantum networks — and perhaps, tantalizingly, this research might also give us some clues on accelerating light beyond the universal speed limit.

24 July 2013

White self-preservation angers some people

A monument on a hill overlooks the Kleinfontein community. "We are here for our culture, for our safety, for our people," said Annatjie Oncke, a resident.

20 July 2013

Canadian scientists helping to unravel the secret of the universe's existence

VANCOUVER - Science is one step closer to solving one of the most profound mysteries in the cosmos due to what an international team of physicists say is an unprecedented observation about a fundamental particle in the universe.

When the universe was created, the Big Bang converted energy into matter and antimatter — two materials that destroy each other when they come into contact.

"In some sense, we're asking why anything exists at all, if it wasn't annihilated by equal quantities of matter and antimatter," Tanaka said in an interview.

"There's some kind of imbalance that occurred when the matter became dominant, and that is something that we can't explain."

"By studying these elementary particles, we're sort of looking at the universe near the time of the Big Bang," he said.

"It gives us a glimpse into what might have happened, what particles where doing, and explaining how the universe started from the Big Bang to where we are now, with galaxies, and molecules and...people.

19 July 2013

World's first mission to the Moon's South Pole announced: cosmic speciation

The world’s first mission to the South Pole of the Moon was announced Thursday, opening up the possibility that the public will be able to access images from the moon online.
 
The private enterprise mission, announced by the International Lunar Observatory Association and Moon Express, Inc., will be both scientific and commercial, and plans to deliver the International Lunar Observatory (ILO) aboard a Moon Express robotic lander.

Artist's depiction of the ILO lunar telescopes that will be delivered by a Moon Express lander (Moon Express)
 
The observatory is intended to establish a base for permanent astrophysical observations and a lunar commercial communications systems for researchers to utilize.
 
“We are very excited to announce that our second Moon mission will be to the lunar South Pole to deliver the International Lunar Observatory and to prospect for resources,” said Moon Express CEO Dr. Robert Richards.  “The mission will provide a historic landing in an unexplored region of the Moon that may harbor some of the greatest resource deposits in the solar system.”
 
If successful, the ILO will be the first private space telescope to operate from the lunar surface and be available to researchers, educators and the general public through the internet.
 
It will allow them to access images from the surface of the Moon, and it is hoped that it will create a new model of “citizen science” public participation and international collaboration.

Chimps, Orangutans Have Human-Like Memory: cosmic Brotherhood of Sentience

Now, a new study published today in Current Biology shows that captive chimpanzees and orangutans can quickly recall past events like people. Chimpanzees are our closest relatives.
 
A chimpanzee named Frodo seems to pose in Gombe Stream National Park, Tanzania.
 
“I think [the study] tells us that our memory systems are not unique,” said study co-author Gema Martin-Ordas, a postdoctoral researcher.
 
 
Chimps and orangutans ”share some features of autobiographical memories that humans have, but we can’t be sure whether they’re aware of those memories, and that’s the debate,” Martin-Ordas said.
 
The science of memory storage and remembrance is still a field in its infancy: The brain is such a complex organ that it’s difficult to pinpoint exact memory-storage processes. (See a 3-D memory interactive.)

CIA said to back study on ways to hack the global climate

This file graphic illustrates techniques to cool the Earth via a thin cloud of aerosols, including, from left, artillery cannons, a miles-long tower, military aircraft and stratospheric balloons. (Brian West / American Geophysical Union)
 
The U.S. intelligence community is helping to fund a study that is evaluating ways to cool the global climate, including proposals to pump the skies full of sunlight reflecting particles and build machines that vacuum greenhouse gases from the atmosphere.
 
A final report is tentatively scheduled for release in the spring or summer of 2014 by the National Academy of Sciences, which has convened a committee of science and policy experts to study the issue.
 
As for concerns that intelligence community funding will make some or all of the committee's findings secret, Rugani said not to worry.
"The report is unclassified. It will be conducted in the public sphere and will be made available to the public in its entirety once it is completed," she said. "So, there's nothing nefarious going on here."

Gut Microbes Can Split a Species: holonic hologram

Here's how to create a new species. Put animals—say finches—from the same species on separate islands and let them do their thing for many, many generations. Over time, each group will adapt to its new environment, and the genomes of the two populations will become so different that if you reintroduce the animals to the same habitat, they can no longer breed successfully. Voilà, one species has become two. But a new study suggests that DNA isn't the only thing that separates species: Some populations diverge because of the microbes in their guts.
The paper is "important and potentially groundbreaking," says John Werren, a biologist at the University of Rochester in New York. "Scientists have studied speciation … for many years, and this opens up a whole new aspect to it."
 
Bordenstein goes one step further. The genes of microbes harbored by an organism are just as important for evolution as the genes in its own cells, he says, calling both together a "hologenome."

Newborn Star's 'Snow Line' Reveals Clues About Planet Formation

The location of the snow lines for volatiles can affect planetary formation. Recent research has indicated the water snow line, shown here, lies farther out than previously suspected. Credit: NASA, ESA, and A. Feild (STScI)
 
Astronomers have identified the point where carbon monoxide (CO) freezes in the disk around a sunlike star — information that could help them understand how planets form.

A team of international scientists has calculated the CO "snow line" for a star called TW Hydrae, determining that the gas solidifies at about the distance of the orbit of Neptune, where it could help feed the formation of the outer edges of the system.

"The CO snow line is interesting, not only because CO is abundant in the disks, but its snow line is the most accessible to direct observations due to its low freeze-out temperature — it's farther away from the star," said principal investigator Chunhua Qi of the Harvard-Smithsonian Center for Astrophysics. "It could mark the starting point where smaller icy bodies, like comets, and dwarf planets, like Pluto, would begin to form."
 Stars form when a disk of dust and gas collapses in on itself due to gravity. The remaining material continues to orbit the newly formed object in a disk of material.
 
As dust and gas particles pass through the disk, scientists say, they come together to form larger and larger clumps that can eventually grow into planets. Frozen volatiles help this process along.
 
"The snow line provides more sticky solid grains, and enhances the planet formation efficiency and grain growth," Qi told SPACE.com in an email. But determining the location of these grains can be a challenge. Emission from volatiles along the outside of the disk can make it difficult for scientists to image the telltale signs of frozen compounds.
 

Star light, star bright

47 Tucanae, 16,700 light-years from Earth, is 10.5 billion years old and one of the brightest of our galaxy’s globular clusters.
 
UBC astronomers have used NASA’s Hubble Space Telescope to track the orbital motion of 33,000 stars in one of the galaxy’s oldest globular clusters, offering new insights into the formation of the Milky Way.
 
The careful examination of “cosmic choreography” enabled researchers, for the first time, to link the movement of stars within the cluster to the stars’ ages. The study reveals two distinct generations of stars within globular cluster 47 Tucanae, 16,700 light-years from Earth.
 
The lack of heavier elements in the population of older, redder stars reflects the initial composition of the gas that formed the cluster. After the most massive of these stars completed their stellar evolution, they expelled gas enriched with heavier elements back into the cluster. This gas collided with other gas and formed a second, more chemically enriched generation of bluer stars that was concentrated toward the cluster centre. Over time these stars moved slowly outward into more elliptical orbits.
 
This is not the first time Hubble has revealed multiple generations of stars in globular clusters. In 2007, Hubble researchers found three generations of stars in the massive globular cluster NGC 2808. But Richer’s team is the first to link stellar dynamics to separate populations.
 
Astronomers need to continue analyzing these multiple generations to better understand how stars formed in distant galaxies in the early universe.

18 July 2013

Newly discovered “Pandoravirus" could redefine life as we know it

The genome of Megavirus chilensisa, the previous record holder for largest virus, with 1,200 genes. The new pandoravirus has roughly 2,500 genes. (Photo: Wikimedia)
 
The discovery of two new jumbo-sized viruses is blurring the lines between viral and cellular life and could point to the existence of a new type of life, scientists suggest.
 
The two large viruses, detailed in this week's issue of the journal Science, have been dubbed "Pandoraviruses" because of the surprises they may hold for biologists, in reference to the mythical Greek figure who opened a box and released evil into the world.
 
The discovery of Pandoraviruses is an indication that our knowledge of Earth's microbial biodiversity is still incomplete, explained study coauthor Jean-Michel Claverie, a virologist at the French National Research Agency at Aix-Marseille University.
 
"Huge discoveries remain to be made at the most fundamental level that may change our present conception about the origin of life and its evolution," Claverie said.

16 July 2013

Decapitated worms can regenerate their brains, and the memories stored inside: harmonic bio-immanence

As for where these memories are coming from, the researchers don’t really know. They speculate that the memories might be stored elsewhere in the body, perhaps in the neurons that make up the worm’s nervous system (see the network diagram in the image above). It is possible that the nervous system also learns something during training, and then somehow these neurons play a role in the recreation of old memories when the brain is regenerated.
 
A lot more research will need to be done to work out exactly what’s going on here — and more importantly, whether other animals, including humans, also store memories outside of the brain.

14 July 2013

Antarctic Lake Vostok: Inhospitable Lake Somehow Full Of Life, Could This Mean Species On Mars?

The Vostok research facility in Antarctica. (Photo : Reuters)
 
Lake Vostok, hidden beneath an Antarctic glacier, is so deep and cold that it resembles an alien planet where life should be impossible Scientists have discovered a surprising amount of critters beneath the frigid water.

The researchers identified billions of species through DNA and RNA sequencing, in a place where life should not be able to exist, according to a Bowling Green State University press release.
 
"The bounds on what is habitable and what is not are changing," Dr. Scott Rogers, a Bowling Green State University professor of biological sciences who worked on the study, said.
 
Lake Vostok is the fourth deepest lake on Earth, and the largest sub glacial lake known in Antarctica.
The lake is under high pressure thanks to 1.5 million years-worth of ice coverage and a depth of nearly two miles.
Due to the lake's conditions there are almost no nutrients available. It lies below sea level and experiences harsh and unpredictable weather conditions.
 
Scientists thought the lake's conditions rendered it inhospitable to all types of life, even bacteria.
The team proved past speculations wrong when they examined the underside of the million-year-old ice.
 
"We found much more complexity than anyone thought," Rogers said. "It really shows the tenacity of life, and how organisms can survive in places where a couple dozen years ago we thought nothing could survive."

Primeval underwater forest discovered in Gulf of Mexico

Scuba divers have discovered a primeval underwater forest off the coast of Alabama.
 
The bald cypress forest was buried under ocean sediments, protected in an oxygen-free environment for more than 50,000 years, but was likely uncovered by Hurricane Katrina in 2005, said Ben Raines, one of the first divers to explore the underwater forest and the executive director of the nonprofit Weeks Bay Foundation, which researches estuaries.
 
The forest contains trees so well-preserved that when they are cut, they still smell like fresh cypress sap, Raines said.
 
The stumps of the cypress trees span an area of at least 0.5 square miles (0.8 kilometers), several miles from the coast of Mobile, Ala., and sit about 60 feet (18 meters) below the surface of the Gulf of Mexico.

Immersed & Permeated

NASA's Interstellar Boundary Explorer, or IBEX, recently mapped the boundaries of the solar system's tail, called the heliotail. By combining observations from the first three years of IBEX imagery, scientists have mapped out a tail that shows a combination of fast and slow moving particles. The entire structure twisted, because it experiences the pushing and pulling of magnetic fields outside the solar system.

12 July 2013

WeinerSpitzer: Welcome to the desert of the real

 
Five years after a prostitution scandal forced former New York Gov. Eliot Spitzer from office, many Democrats appear willing to give him a shot at political redemption, according to a new poll that shows him with a strong lead in the city comptroller race.
Spitzer only announced his candidacy Sunday, and it isn't yet clear whether he will gather enough signatures by a Thursday deadline to make the Sept. 10 Democratic primary ballot. But 42 percent of registered Democrats already say they support Spitzer, compared to 33 percent for his potential rival, Manhattan Borough President Scott Stringer, the NBC 4 New York/Wall Street Journal/Marist Poll shows.
 
The second coming of disgraced and oversexed pols Anthony Weiner (quite probably the next mayor of New York City) and Eliot Spitzer (who has announced a bid for city comptroller) helps to explain widespread and growing contempt for government:

In a comprehensive survey of public attitudes done last September, Gallup found that just 19 percent of Americans think they “can trust the government in Washington to do what is right” “just about always” or “most of the time.” The latest CNN/ORC poll, from mid-June, shows large majorities convinced that Obama is failing on the economy, the deficit, foreign policy, civil liberties, and just about everything else. The one upside? He’s still doing better than Congress.

06 July 2013

Radio waves from young universe stun scientists

LONDON: Scientists have detected mysterious bursts of radio waves that last only for a tenth of a blink of an eye, originating billions of light years away. A single burst of radio emission of unknown origin was detected outside the Earth's galaxy about six years ago, but no one is certain what it was or even if it was real. Scientists have spent the last four years searching for more of these explosive, short-duration radio bursts.

This image obtained on July 4, 2013 from Nasa's Galaxy Evolution Explorer shows NGC 6744, one of the galaxies most similar to our Milky Way in the local universe. The galaxy is situated in the constellation of Pavo at a distance of about 30 million light-years. NGC 6744 is bigger than the Milky Way, with a disk stretching 175,000 light-years across. (AFP Photo)

However, a paper published on Friday described four more such bursts, removing any doubt that they are real. The radio bursts last for just a few milliseconds and the furthest one detected was several billion light years away.

The international research team rule out terrestrial sources for the four fast radio bursts and say their brightness and distance suggest they come from cosmological distances when the universe was just half its current age.

The burst energetics indicate that they originate from an extreme astrophysical event involving relativistic objects such as neutron stars or black holes.

Study lead Dan Thornton from England's University of Manchester said the findings pointed to some extreme events involving large amounts of mass or energy as the source of the radio bursts.

Astonishingly, the findings — taken from a tiny fraction of the sky — also suggest that there should be one of these signals going off every 10 seconds.

05 July 2013

White man's skull has Australians scratching heads

A centuries-old skull found in northern New South Wales in late 2011, in Canberra. The skull of a White man is raising questions about whether Captain James Cook really was the first European to land on the country's east coast. (AFP)

The centuries-old skull of a White man found in Australia is raising questions about whether Captain James Cook really was the first European to land on the country's east coast.
 
The skull was found in northern New South Wales in late 2011, and police initially prepared themselves for a gruesome murder investigation. But scientific testing revealed that not only was it much older than expected, but possibly belonged to a White man born around 1650, well before Englishman Cook reached the eastern seaboard on the Endeavour in 1770. "The DNA determined the skull was a male," Detective Sergeant John Williamson told The Daily Telegraph. "And the anthropologist report states the skull is that of a Caucasoid aged anywhere from 28 to 65."
Australian National University expert Stewart Fallon, who carbon-dated the skull, pulling some collagen from the bone as well as the enamel on a tooth, said he was at first shocked at the age of the relic.
 
"We didn't know how old this one was, we assumed at first that it was going to be a very young sample," he told AFP. "When we first did it we weren't really thinking about people coming to Australia and things like until we started to look at the dates and say, 'Oh, that's becoming intriguing'." He said the test used was quite accurate for dates after 1950 but for earlier samples it was more difficult, and the two samples yielded different dates - though both were within the error range. "Using them (the dates) together we can do some modelling as to what we expect the calendar age to be ... and the way it works out by using those two dates is that we get about an 80 percent probability that the person was born somewhere around the 1650s and died somewhere between 1660 and 1700," Fallon said.
 
He said there was a 20 percent probability the skull, which was found well-preserved and intact but without any other remains near the Manning River, belonged to someone born between 1780 to 1790 who died between 1805 and 1810. Historians were cautious. "Before we rewrite the history of European settlement we have to consider a number of issues, particularly the circumstances of the discovery," archaeologist Adam Ford told the Telegraph. "The fact the skull is in good condition and found alone could easily point to it coming from a private collection and skulls were very popular with collectors in the 19th century."
 
Cassie Mercer, editor of Australia And New Zealand Inside History, said the skull "could be an incredible find." "I guess it's a very exciting find because it could open up a whole lot of avenues of history that we haven't been able to explore before," she told AFP. Dutch explorers made the earliest European landings in Cape York in Australia's far north and western Australia in the 1600s.
 

Early galaxy may reveal answers about our own Milky Way

Quasars are among the brightest objects in the universe and can be used as lighthouses to study the universe between the quasars and Earth. Here researchers have discovered a galaxy that lies in front of a quasar and by studying the absorption lines in the light from the quasar, they have measured the elemental composition in the galaxy in great detail, despite the fact that we are looking approx. 11 billion years back in time. / Niels Bohr Institute, Chano Birkelind
 
Researchers are looking to the stars to find out more about the origin story of our own galaxy.
Using data gathered by the ESO Very Large Telescope and the Hubble Space Telescope, researchers have been able to determine the size, mass, content of elements that make up another early galaxy and figured out how quickly it can form stars.

"Galaxies are deeply fascinating objects. The seeds of galaxies are quantum fluctuations in the very early universe and thus, understanding of galaxies links the largest scales in the universe with the smallest. It is only within galaxies that gas can become cold and dense enough to form stars and galaxies are therefore the cradles of star's births," co-lead researcher Johan Fynbo, professor at the Dark Cosmology Centre at the Niels Bohr Institute at the University of Copenhagen, said in a press release.

Back when the universe was forming, galaxies were created from large clouds of gas and dark matter. When gas cools down, it becomes so dense and compact that it collapses in on itself when gravity's pressure heats up its matter. That process creates a glowing ball of gas, or what we call a star.

Inside the stars, hydrogen and helium melt and form heavier elements carbon, nitrogen, oxygen. Eventually, magnesium, silicon and iron are formed. When the core of the star has turned to iron, no more energy can be taken out, and the star burns out and dies in a supernova explosion. This causes clouds of gas and other elements to be shot out into space, where new gas clouds form. The gas clouds cool and eventually become dense, the star process begins again.

Earlier stars only had 1/1000th of the amount of elements found in our own Sun. Today's galaxies have more stars and not as much gas compared to earlier galaxies. This means that newer stars contain even more elements, and heavier ones at that.

To figure out how the changes affect newer galaxies, researchers located a galaxy that started forming 11 billion years ago. In comparison, our galaxy, the Milky Way, is 13.2 billion years old.
"We want to understand this cosmic evolutionary history better by studying very early galaxies. We want to measure how large they are, what they weigh and how quickly stars and heavy elements are formed," co-lead researcher Johan Fynbo, a PhD student at the Dark Cosmology Centre at the Niels Bohr Institute, said

The researchers followed a quasar, an active black hole that is brighter than a galaxy, to determine the location of the young galaxy. They were able to see the recently formed stars in the galaxy and figure out how many stars there were in relation to the total mass, which they calculated from stars and available gas.

This allowed them to figure out that heavier elements are equally spread throughout the younger galaxy, and that stars formed in the center of the galaxy help provide more gas for new stars in the outer regions.

The new stars also only contain about 1/3 as much oxygen as our Sun's original content. This means stars made at least 11 billion years ago and earlier may have enough elements to create livable habitats like the Earth.

The study was published on Tuesday in Monthly Notices of the Royal Astronomical Society.

04 July 2013

The Lion’s Share of Galaxies

The Universe is built in layers. The fundamental units, you could argue, are stars. Some are solitary (like the Sun), some orbit each other as binary stars. By the hundreds or thousands they comprise clusters, and if you have a few billion to a few hundred billion, you get a galaxy.
 
Our Milky Way is part of a small group of about 50 other galaxies, most of which are smallish dwarfs. The next step up from a group is a galaxy cluster, which can contain hundreds to thousands of galaxies.
 
One of the nearest galaxy clusters is Abell 1367, more commonly called the Leo Cluster. A search of the astronomical literature shows it’s unclear how many galaxies can be considered Leo citizens; there are at least 70 major galaxies and perhaps many more. It’s 300 million light-years away in the constellation of Leo (of course).
 
And it’s gorgeous. Astronomer Adam Block took an amazing image of the central region of the cluster using the 0.81 meter Schulman telescope on Mt. Lemmon in Arizona:
 
A city of galaxies: the Leo Cluster.
 
And it goes up from there. The Coma Supercluster, along with many others, forms a structure called the Great Wall, a vast complex hundreds of millions light-years long. It’s one of the largest structures in the entire Universe, but there are many like it.
 
It’s incredible, mind-numbing. The scale of the Universe crushes our sense of size, fills our capacity of awe to overflowing. I know some people despair when they think about this, but it has the opposite effect on me: I am uplifted. Not only is it wonderful enough that such things exist at all, but how astonishing is it that we can see them, study them, understand them? Perhaps not completely, of course, not yet and perhaps never in their entirety.
 
But we can try. And that makes us important, even at the tiny, tiny scale of this vast, vast Universe we inhabit.

Great ape genetic diversity catalog frames primate evolution and future conservation

 
"By avoiding inbreeding to produce a diverse population, zoos and conservation groups may be entirely eroding genetic signals specific to certain populations in specific geographic locations in the wild," Sudmant said. One of the captive-bred apes studied by the researchers, Donald, had the genetic makeup of two distinct chimpanzee subspecies, located about 2,000 kilometers away from each other in the wild.

The research also delineates the many changes that occurred along each of the ape lineages as they became separated from each other through migration, geological change and climate events. The formation of rivers, the partition of islands from the mainland, and other natural disturbances have all served to isolate groups of apes. Isolated populations may then be exposed to a unique set of environmental pressures, resulting in population fluctuations and adaptations depending on the circumstances.

Even though early human-like species were present at the same time as the ancestors of some present day great apes, the researchers found that the evolutionary history of ancestral great ape populations was far more complex than that of humans. Compared to our closest relatives, chimpanzees, human history appears "almost boring" conclude Sudmant and his mentor Evan Eicher. The last few million years of chimpanzee evolutionary history are fraught with population explosions followed by implosions demonstrating remarkable plasticity. The reasons for these fluctuations in chimpanzee population size long before our own population explosion are still unknown however.

Sudmant said his interest in studying the great apes, and wanting to preserve great ape species, stems from the similarity of great apes to humans and their curiosity about us.

"If you look at a chimpanzee or a gorilla, those guys will look right back at you," he said, "They act just like us. We need to find ways to protect these precious species from extinction."

Revolutionary instrument delivers a sharper universe to astronomers

Astronomers recently got their hands on Gemini Observatory’s revolutionary new adaptive optics system, called GeMS. “And the data are truly spectacular!” said Robert Blum, deputy director of the National Optical Astronomy Observatory with funding from the U.S. National Science Foundation. “What we have seen so far signals an incredible capability that leaps ahead of anything in space or on the ground — and it will for some time.” Blum is currently using GeMS to study the environments in and around star clusters, and his preliminary data, targeting the spectacular cluster identified as RMC 136, are among the set of seven images being released. The remaining six images — spanning views from violent star-forming regions to the graceful interaction of distant colliding galaxies — only hint at the diversity of cutting-edge research that GeMS enables.

After more than a decade in development, the system, now in regular use at the Gemini South Telescope in Chile, is streaming ultra-sharp data to scientists around the world — providing a new level of detail in their studies of the universe. The images now being made public show the scientific discovery power of GeMS (derived from the Gemini Multi-conjugate adaptive optics System), which uses a potent combination of multiple lasers and deformable mirrors to remove atmospheric distortions (blurriness) from ground-based images.
 
  NGC 4038
This multiple pointing, 3-band, near-infrared image obtained with GeMS/GSAOI reveals remarkable, colorful details in NGC 4038, one of the components of the Antennae Galaxies (NGC 4038/NGC 4039), despite a short total exposure time.
Stuart Ryder of the Australian Astronomical Observatory, with funding through the Australian Research Council, whose work requires crisp images of distant galaxies to reveal exploding stars (supernovae), also anticipates the potential of GeMS for his research. But mostly he’s blown away by the raw technology involved. “I was fortunate enough to witness GeMS/GSAOI in action, and I was awestruck by the sight of the yellow-orange laser beam piercing the clear, moonlit night,” said Ryder. “When one considers all the factors that have to work together, from clear skies to a steady stream of meteors burning up in the upper atmosphere sprinkling enough sodium atoms to be excited by the laser — it’s wonderful to see it all come together.”

01 July 2013

"Twisted light" idea makes for terabit rates in fibre

A novel way of boosting data rates in optical communication using "twisted light" has been shown to work in optical fibres.

The light is effectively corkscrew-shaped, and more data can be encoded in differently twisted beams.

The concept had been shown off over "free space" but it remained unclear if it would work in fibres.

Now a team reporting in Science has demonstrated data rates of 1.6 terabits per second over 1km of optical fibre.

This is still short of the "over-the-air" rate of 2.5 Tb/s demonstrated by members of the same team in 2012. But it is a powerful proof of principle for adapting the technique to use with fibres in, for example, data centres.

The idea behind twisted light is based on the fact that photons, the most basic units of light, carry two kinds of momentum - a kind of energy in their movement.
"Spin angular momentum" is better known as polarisation. Photons "wiggle" along a particular direction, and different polarisations can be separated out by, for example, polarising sunglasses or 3D glasses.

But they also carry what is called orbital angular momentum. This is best explained in analogy to the Earth-Sun system: our planet spinning around its axis manifests spin angular momentum, while the orbital angular momentum is seen in our revolution around the Sun.

"Twisted light" approaches use this orbital angular momentum, essentially encoding more data in varying degrees of twist.

Interstellar gas allows chemical reactions caused by quantum tunneling

The gas cloud around these stars could be undergoing chemical reactions that we had previously thought were impossible. (NASA)
 
In recent years, astronomers have detected some simple organic chemicals in the disks of material surrounding some stars. In our own Solar System, these seem to have undergone reactions that converted them into more complex molecules - some of them crucial for life - that have been found on meteorites.
 
So, understanding the reactions that can take place in space can help provide an indication of the sorts of chemistry available to start life both here and around other stars.
 
Based on a publication in Nature Chemistry, it seems that the chemistry that can take place in the cold clouds of gas of space is much more complex than we had predicted. Reactions that would be impossible under normal circumstances - simply because there's not enough energy to push them forward - can take place in cold gasses due to quantum mechanical effects. That's because one of the reactants (a hydrogen nucleus) can undergo quantum tunneling between two reactants.
 
The fact that quantum tunneling allows reactions that would never take place in their own right is pretty impressive. But the results are also important because they give us a clearer picture of what's likely to be going on in the neighborhood of distant stars. Because of their distance, it's hard to detect anything other than raw materials around them. To infer the actual chemistry of the gas clouds, we have to look at the raw materials and the conditions, then figure out what reactions are likely to take place.
 
By confirming that otherwise-impossible reactions can take place in these gas clouds, the authors have greatly expanded the range of chemistry we can expect to be taking place. And that can tell us something about the chemicals that are likely to be present in any planets formed under similar conditions.

60 Billion Alien Planets Could Support Life, Study Suggests

An artist's concept illustrates a young, red dwarf star surrounded by three planets. ( NASA)
 
Looking for life beyond Earth? You now have twice as many planets to explore.
 
According to a study published in Astrophysical Journal Letters, there may be as many as 60 billion exoplanets in the so-called habitable zone around their stars - double what was previously thought.
 
Why the jump? Because a team of scientists from the University of Chicago and Northwestern University has created a 3-D model of how clouds would affect temperatures on alien worlds.
 
To be in a habitable zone, a planet needs to be just the right distance from its star so that liquid water (considered a requisite for life as we know it)  can exist on the planet's surface.
 
If the planet is too near its star, the liquid water would turn to vapor; too far away, and the water would turn to ice.
 
For decades, scientists have determined whether a planet is in this liquid-water-friendly Goldilocks zone by calculating how far the planet is from its star, and how hot the star is burning.
 
But in the new study, astronomers at the University of Chicago show how cloud patterns can alter the temperature of a planet enough that planets that were previously considered too close to their stars to support liquid water might be able to support it after all.