Science & TechnologyS


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Easter Island Discovery Sends Archaeologists Back to Drawing Board

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© Unknown
Archaeologists have disproved the fifty-year-old theory underpinning our understanding of how the famous stone statues were moved around Easter Island.

Fieldwork led by researchers at University College London and The University of Manchester, has shown the remote Pacific island's ancient road system was primarily ceremonial and not solely built for transportation of the figures.

A complex network of roads up to 800-years-old crisscross the Island between the hat and statue quarries and the coastal areas.

Laying alongside the roads are dozens of the statues- or moai.

The find will create controversy among the many archaeologists who have dedicated years to finding out exactly how the moai were moved, ever since Norwegian adventurer Thor Heyerdahl first published his theory in 1958.

Heyerdahl and subsequent researchers believed that statues he found lying on their backs and faces near the roads were abandoned during transportation by the ancient Polynesians.

Radar

'Zombie' satellite runs amok in Earth's orbit

Galaxy 15
© Newscom/FileIntelsat's Galaxy 15 satellite launched in 2005 with an Ariane 5 rocket in Guyana. The communications satellite stopped responding last month, becoming a 'zombie' satellite that now threatens other spacecraft
The out-of-control communications satellite Galaxy 15 is drifting into orbits occupied by other spacecraft.

An attempt to shut down the electronics payload of the out-of-control communications satellite Galaxy 15 has failed, leaving the satellite - which ceased responding to ground commands last month - still in its uncontrolled "zombiesat" drift toward orbits occupied by other spacecraft, the satellite's fleet operator Intelsat said Tuesday.

Galaxy 15 is closing in on the geostationary orbital slot occupied by another C-band satellite, the AMC-11 spacecraft operated by SES World Skies, and with its stuck-on communications payload will be in a position to cause potentially severe interference with the SES satellite during a two-week period starting around May 23, according to Intelsat and SES estimates.

Info

Magnetically-Induced Hallucinations Explain Ball Lighting, Say Physicists

TMS
© ArXiv.org
Powerful magnetic fields can induce hallucinations in the lab, so why not in the real world, too? Transcranial magnetic stimulation (TMS) is an extraordinary technique pioneered by neuroscientists to explore the workings of the brain. The idea is to place a human in a rapidly changing magnetic field that is powerful enough to induce currents in neurons in the brain. Then sit back and see what happens.

Since TMS was invented in the 1980s, it has become a powerful way of investigating how the brain works. Because the fields can be tightly focused, it is possible to generate currents in very specific areas of the brain to see what they do.

Focus the field in the visual cortex, for example, and the induced eddys cause the subject to 'see' lights that appear as discs and lines. Move the the field within the cortex and the subject sees the lights move too.

All that much is repeatable in the lab using giant superconducting magnets capable of creating fields of as much as 0.5 Tesla inside the brain.

But if this happens in the lab, then why not in the real world too, say Joseph Peer and Alexander Kendl at the University of Innsbruck in Austria. They calculate that the rapidly changing fields associated with repeated lightning strikes are powerful enough to cause a similar phenomenon in humans within 200 metres.

Heart

Evidence Growing of Air Pollution's Link to Heart Disease, Death

The scientific evidence linking air pollution to heart attacks, strokes and cardiovascular death has "substantially strengthened," and people, particularly those at high cardiovascular risk, should limit their exposure, according to an updated American Heart Association scientific statement.

The evidence is strongest for fine particulate matter (PM2.5) having a causal relationship to cardiovascular disease, said the expert panel of authors who updated the association's 2004 initial statement on air pollution, also published in Circulation: Journal of the American Heart Association.

The major source of PM2.5 is fossil fuel combustion from industry, traffic, and power generation. Biomass burning, heating, cooking, indoor activities and forest fires may also be relevant sources, particularly in certain regions.

"Particulate matter appears to directly increase risk by triggering events in susceptible individuals within hours to days of an increased level of exposure, even among those who otherwise may have been healthy for years," said Robert D. Brook, M.D., lead author of the statement, which was written after review of epidemiological, molecular and toxicological studies published during the past six years.

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Space technology revolutionizes archaeology, understanding of Maya

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© Caracol Archaeological ProjectUniversity of Central Florida researchers led a NASA-funded research project in April 2009 that collected the equivalent of 25 years worth of data in four days. Aboard a Cessna 337, LiDAR (Light Detection and Ranging) equipment bounced laser beams to sensors on the ground, penetrating the thick tree canopy and producing images of the ancient settlement and environmental modifications made by the inhabitants of the Maya city of Caracol. This LiDAR image shows the density of terracing in the Ceiba terminus area
A flyover of Belize's thick jungles has revolutionized archaeology worldwide and vividly illustrated the complex urban centers developed by one of the most-studied ancient civilizations -- the Maya.

University of Central Florida researchers led a NASA-funded research project in April 2009 that collected the equivalent of 25 years worth of data in four days.

Aboard a Cessna 337, LiDAR (Light Detection and Ranging) equipment bounced laser beams to sensors on the ground, penetrating the thick tree canopy and producing images of the ancient settlement and environmental modifications made by the inhabitants of the Maya city of Caracol within 200 square kilometers (77 square miles).

Pharoah

Church and Nilometer discovered on Egypt's Avenue of Sphinxes

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© Supreme Council of AntiquitiesRestoration works at the Avenue of Sphinxes.
Archaeologists working at the Avenue of Sphinxes in Luxor, Egypt, have uncovered the remains of a fifth century Coptic church and a Nilometer, a structure used to measure the level of the Nile during floods.

According to a statement released by Egypt's Supreme Council of Antiquities (SCA), the remains of the church were found on the second of five sections of the ancient religious path leading to the Karnak temple.

Meteor

Is Halley's comet an alien interloper?

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© Royal Observatory, Edinburgh/AAO/SPLStolen from a stellar nursery
Our sun may have stolen the vast majority of its comets from other stars. The theft could explain the puzzling profusion of objects in a huge reservoir surrounding the sun called the Oort cloud.

The Oort cloud is a collection of comets thought to orbit the sun in a roughly spherical halo about 50,000 times as far from the sun as Earth - at the outer edge of the solar system. How did the comets get there? In the standard picture, they formed much closer to the sun, then migrated outward in a two-stage process.

First, the gravity of the giant planets flung them into elongated orbits to form a population called the scattered disc. Objects in the scattered disc come about as close to the sun as Neptune, but venture dozens of times further out, to more than 1000 times the Earth-sun distance. That far from the sun, the gravitational pull of the galaxy becomes significant, so many of the scattered-disc objects get pulled out to populate the Oort cloud.

There is a problem with this picture, however. Simulations have long predicted that this process could only populate the Oort cloud with 10 times as many comets as are currently in the scattered disc, while estimates based on observed comets suggest the ratio is more like 700 to 1.

Info

A new science project on the historical and natural heritage of the Pyrenees

'The Origins Route' will help to make scientific knowledge generated in the area contribute to its economic development.

Six Spanish and French institutions are working jointly to put into action "The Origins Route", a scientific dissemination project to develop a quality sustainable model for tourism in the Pyrenees. Participating is also the Centre for the Studies of Archaeological and Prehistoric Heritage (CEPAP) of Universitat Autònoma de Barcelona (UAB). The initiative comprises a set of activities to inform society about the origins of the Pyrenees in fields related to astronomy, geology, palaeontology and human evolution.

Blackbox

The imperfect universe: Goodbye, theory of everything

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© NASA/ESACould an untidy universe have helped complex life emerge?
Fifteen years ago, I was a physicist hard at work hunting for a theory of nature that would unify the very big and the very small. There was good reason to hope. The great and the good were committed. Even Einstein, who recognised that our understanding of reality is necessarily incomplete, had spent the last 20 years of his life searching for a unified field theory that would describe the two main forces we see acting around us - gravity and electromagnetism - as manifestations of a single force. For him, such a mathematical theory represented the purest and most elegant expression of nature and the highest achievement of the human intellect.

Fifty-five years after Einstein's death, the hunt for this elusive unified field theory continues. To physicist Stephen Hawking and many others, finding the "theory of everything" would be equivalent to knowing the "mind of God". The metaphor is not accidental.

Modern critics say that Einstein and other giants of 20th-century physics (including Wolfgang Pauli, Erwin Schrödinger and Werner Heisenberg) failed because their models didn't include all particles of matter and their fundamental interactions. Factor them in, they argue, and we stand a much better chance of success. Dreams of a final theory (as a book on the subject, by Nobel laureate Steven Weinberg, was titled) live on, stronger than ever.

But are we really getting any closer? Do we dare ask whether the search is fundamentally misguided? Could belief in a physical theory that unifies the secrets of the material world - a "hidden code" of nature - be the scientific equivalent of the religious belief in oneness held by the billions who go to churches, mosques and synagogues every day?

Sherlock

Soft Tissue Remnants Discovered in Archaeopteryx Fossil

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© W. I. Sellers/Proceedings of the National Academy of SciencesChemistry in colour
It boasts more than just beautiful impressions of long-gone feathers. One of the world's most famous fossils - of the earliest known bird, Archaeopteryx - also contains remnants of the feathers' soft tissue.

"It's amazing that that chemistry is preserved after 150 million years," says Roy Wogelius, a geochemist at the University of Manchester, UK. Wogelius and colleagues scanned the "Thermopolis specimen" using a powerful X-ray beam from a synchrotron at the Stanford Synchrotron Radiation Lightsource in California.

The synchrotron excites atoms in target materials to emit X rays at characteristic wavelengths. The scan reveals the distribution of elements throughout the fossil. The green glow of the bones in this false-colour image shows that Archaeopteryx, like modern birds, concentrated zinc in its bones. The red of the rocks comes from calcium in the limestone that had encased the fossil since the animal died.

Copper and zinc are key nutrients for living birds, and their presence in the fossil bones shows the evolutionary link with dinosaurs. The study also revealed phosphorous along the main shaft of the feathers in the fossil: palaeontologists had long thought that only impressions remained.