Joseph Schuman Senior Correspondent
AOL News
(March 28) -- Was it long-term climate change, rather than a rogue asteroid, that killed off the dinosaurs?
That's the conclusion of German paleontologist Michael Prauss, who studied 65-million-year-old fossils drilled out of the earth in the Brazos River area of Texas and argues that radical changes to the flora and fauna of the era began long before arrival of the massive space rock widely associated with one of the largest mass extinctions in the history of the planet.
That impact, at what is now Chicxulub, Mexico, in the past 30 years has become the primary suspect in the death of the dinosaurs. And it was the subject of an article in the journal Science earlier this month in which 41 scientists from around the world argued that a wealth of global data show the extinctions began at the same time that the asteroid's crash sent debris across the atmosphere and blocked out the sun for years.
Illustration of herd of Hadrosaurus running away from fire.
DEA Picture Library/Getty Images
A German scientist refutes the widely accepted theory that an asteroid led to dinosaurs' extinction, saying long-term climate change was to blame instead. Above, an illustration shows a herd of Hadrosaurus running away from fire.
But Prauss, writing in next month's edition of the journal Palaeogeography, Palaeoclimatology, Palaeoecology and working with Princeton paleontologist Gerta Gerta Keller -- a well-known critic of the Chicxulub theory -- maintained the impact was just one in a chain of catastrophic events that caused substantial environmental upheaval.
"The resulting chronic stress, to which of course the meteorite impact was a contributing factor, is likely to have been fundamental to the crisis in the biosphere and finally the mass extinction," Prauss said.
Those events include the massive, years-long volcanic activity in what is now the Deccan Plateau of India, and which, like the Chicxulub asteroid impact, is conventionally used by paleontologists to separate the Cretaceous period from the Paleogene period.
The Cretaceous, with a relatively warm climate a high sea levels, was the last era of the dinosaurs and the large marine reptiles that lived at the same time. And Prauss also takes issue with other paleontologists' use of Chicxulub as the historical demarcation point.
"The actual impact took place well before the geochemically and micropaleontologically defined Cretaceous Paleogene boundary," he said.
In support of his theories, Prauss cites his analysis of samples taken from drill cores and rock sections dating to the Cretaceous-Paleogene boundary near Brazos, which is about 620 miles from the Chicxulub crater.
The appearance and distribution of microfossils -- the remains of algae, pollen and plant spores -- demonstrate that significant and persistent variations of the ecosystem built steadily over the late Cretaceous and continued over several million years, Prauss said. They can especially be seen in the fluctuation of sea levels and productivity of marine algae, and the so-called fern spike -- a widespread surge in fern spores that signaled landscapes were repopulating after an ecosystem was destroyed.
Prauss said the fern spike began well before the Paleogene period began, and that the Cretaceous-Paleogene boundary -- and the asteroid impact -- marked only the peak of a trend that began millions of years earlier.
"In the light of the new data, both of these points have to be refuted," Prauss said.
Earlier this month, when the Chicxulub paper appeared in Science, one of its authors told AOL News that a goal of the team's work was to respond to arguments coming from the minority of paleontologists who cast doubt on the asteroid's role in killing the dinosaurs.
"It is almost impossible to change the skeptics' minds," Tamara Goldin said. "But we hope we can communicate to the scientific community and the public that this impact-induced environmental catastrophe did happen."
Still, it's important to note that both papers are using geological data to tie environmental events to the period that produced the latest dinosaur fossils scientists have found. In other words, paleontologists are dating the scene of the crime and placing environmental suspects at the scene with some pretty strong arguments.
But there's no direct evidence showing what killed the dinosaurs, leaving open a debate that's likely to continue.
2010 AOL Inc. All Rights Reserved.
Sunday, March 28, 2010
Saturday, March 20, 2010
Atom Smasher Smashes Energy Record
Atom Smasher Smashes Energy Record
Carl Franzen Contributor
AOL News
(March 19, 2010) -- From broken down to record breaking, the Large Hadron Collider -- the world's largest, most expensive particle accelerator -- just achieved yet another milestone on the quest to discover the secrets of the physical universe.
Today, scientists at the European Organization for Nuclear Research, known as CERN, proudly announced they had circulated the highest energy particle beams ever produced by humans around the LHC, and on their first attempt, no less.
"It was incredible. I really didn't expect it to go," said Mike Lamont, the head of LHC machine operations, in a video posted on the CERN Web site. "Astounding. I mean, I don't think anyone in their wildest dreams expected us to go to 3.5 TeV. I think to do that on the first try just shows us what a beautiful machine we've got here."
The measurement Lamont refers to, "TeV," stands for "tera-electron volts," a physics term that describes the extremely small amount of kinetic energy one particle gains when it is accelerated. In reaching the new level of 3.5 TeV early this morning, the LHC bested its own previous world record of 0.18 TeV, achieved in November. By contrast, 1 TeV is equal to the energy produced by a flying mosquito.
In two years, CERN scientists aim to accelerate beams of protons at twice as much energy around the LHC, a 17-mile-long underground ring located beneath the Swiss-French border near the city of Geneva.
"A full 7 TeV beam contains as much energy as a Royal Navy aircraft carrier steaming at 12 knots," says Lewis Page at The Register. "Once the beams are up, that energy has to go somewhere in the end: If a single magnet were to fail, for instance, a terrific blast of energy would leave the Collider's ring at that point with consequences much the same as if HMS Invincible had suddenly popped out of nowhere and rammed the tunnel."
Acceleration is only the first part of the much grander experimental process, however, as CERN scientists then point the beams toward one another inside the ring to create a collision, which in turn will produce double the amount of energy of each individual beam. The first collisions of the two 3.5 TeV beams (a 7 TeV total) are set to take place in the coming weeks, according to CERN via ZDNet.
When CERN scientists finally achieve their goal of colliding two 7 TeV beams together next year, they hope to observe in microcosm the same conditions that existed immediately following the "big bang," the widely held theory that the universe emerged from a single, unimaginably violent expansion of particles from one superdense, superhot state some 12 billion to 15 billion years ago.
"As the universe cooled and the temperature fell below a critical value, an invisible force field called the 'Higgs field' was formed together with the associated 'Higgs boson' [particle]," notes CERN's Web site. "The problem is that no one has ever observed the Higgs boson in an experiment to confirm the theory."
One of CERN's ultimate objectives for the LHC is to use it to definitively answer whether such a particle exists or not, which would result in either the confirmation or refutation of the theoretical building blocks of all modern physics. However, the implications of locating the so-called "God particle" have proven to be highly unsettling to some in both the public and scientific spheres.
A widely disseminated and erroneous fear is that the LHC could produce a black hole capable of destroying the Earth. Several individuals have even filed lawsuits against CERN in a bid to stop work on the Large Hadron Collider for this very reason.
In addition, since its construction began in 1995, the LHC has been beset by numerous unforeseen technical obstacles, glitches and bizarre moments of misfortune that have added at least $40 million to its total cost of $4.3 billion, reports the Telegraph.
The list of errors is as long as it is strange: In 2005, a technician was killed by a falling crane. In 2007, "there was a serious failure in a high-pressure test" of three focusing magnets inside the LHC. Finally booted up in October 2008, the LHC was quickly shut down again just a few weeks later after an underground tunnel ruptured, flooding the area with a ton of liquid helium and causing crucial magnets to overheat and fail. In 2009, more leaks were found, further delaying the project's timeline.
That same year, one CERN scientist made headlines after being arrested and charged with "criminal association with a terrorist enterprise," in connection with al-Qaida. Finally, less than a month later, a random bird somehow managed to drop a "bit of baguette" into the machine, causing it to overheat and shut down.
The sheer number and variety of problems eventually led some in the scientific press to speculate that a force from the future or God himself was deliberately sabotaging the Large Hadron Collider to prevent it from unleashing a great catastrophe via its experiments.
However, since being turned back on in November, the LHC has performed "almost flawlessly," according to The Associated Press.
The latest energy achievement also kicks off what is to be the LHC's longest period of continual operation. CERN says it will remain on and accelerating for the next 18 to 24 months. By the end of 2010, however, it will be shut down for a short period of maintenance. And then again, in 2011, it will be turned off for a whole year to undergo more extensive repairs.
2010 AOL Inc. All Rights Reserved.
Carl Franzen Contributor
AOL News
(March 19, 2010) -- From broken down to record breaking, the Large Hadron Collider -- the world's largest, most expensive particle accelerator -- just achieved yet another milestone on the quest to discover the secrets of the physical universe.
Today, scientists at the European Organization for Nuclear Research, known as CERN, proudly announced they had circulated the highest energy particle beams ever produced by humans around the LHC, and on their first attempt, no less.
"It was incredible. I really didn't expect it to go," said Mike Lamont, the head of LHC machine operations, in a video posted on the CERN Web site. "Astounding. I mean, I don't think anyone in their wildest dreams expected us to go to 3.5 TeV. I think to do that on the first try just shows us what a beautiful machine we've got here."
The measurement Lamont refers to, "TeV," stands for "tera-electron volts," a physics term that describes the extremely small amount of kinetic energy one particle gains when it is accelerated. In reaching the new level of 3.5 TeV early this morning, the LHC bested its own previous world record of 0.18 TeV, achieved in November. By contrast, 1 TeV is equal to the energy produced by a flying mosquito.
In two years, CERN scientists aim to accelerate beams of protons at twice as much energy around the LHC, a 17-mile-long underground ring located beneath the Swiss-French border near the city of Geneva.
"A full 7 TeV beam contains as much energy as a Royal Navy aircraft carrier steaming at 12 knots," says Lewis Page at The Register. "Once the beams are up, that energy has to go somewhere in the end: If a single magnet were to fail, for instance, a terrific blast of energy would leave the Collider's ring at that point with consequences much the same as if HMS Invincible had suddenly popped out of nowhere and rammed the tunnel."
Acceleration is only the first part of the much grander experimental process, however, as CERN scientists then point the beams toward one another inside the ring to create a collision, which in turn will produce double the amount of energy of each individual beam. The first collisions of the two 3.5 TeV beams (a 7 TeV total) are set to take place in the coming weeks, according to CERN via ZDNet.
When CERN scientists finally achieve their goal of colliding two 7 TeV beams together next year, they hope to observe in microcosm the same conditions that existed immediately following the "big bang," the widely held theory that the universe emerged from a single, unimaginably violent expansion of particles from one superdense, superhot state some 12 billion to 15 billion years ago.
"As the universe cooled and the temperature fell below a critical value, an invisible force field called the 'Higgs field' was formed together with the associated 'Higgs boson' [particle]," notes CERN's Web site. "The problem is that no one has ever observed the Higgs boson in an experiment to confirm the theory."
One of CERN's ultimate objectives for the LHC is to use it to definitively answer whether such a particle exists or not, which would result in either the confirmation or refutation of the theoretical building blocks of all modern physics. However, the implications of locating the so-called "God particle" have proven to be highly unsettling to some in both the public and scientific spheres.
A widely disseminated and erroneous fear is that the LHC could produce a black hole capable of destroying the Earth. Several individuals have even filed lawsuits against CERN in a bid to stop work on the Large Hadron Collider for this very reason.
In addition, since its construction began in 1995, the LHC has been beset by numerous unforeseen technical obstacles, glitches and bizarre moments of misfortune that have added at least $40 million to its total cost of $4.3 billion, reports the Telegraph.
The list of errors is as long as it is strange: In 2005, a technician was killed by a falling crane. In 2007, "there was a serious failure in a high-pressure test" of three focusing magnets inside the LHC. Finally booted up in October 2008, the LHC was quickly shut down again just a few weeks later after an underground tunnel ruptured, flooding the area with a ton of liquid helium and causing crucial magnets to overheat and fail. In 2009, more leaks were found, further delaying the project's timeline.
That same year, one CERN scientist made headlines after being arrested and charged with "criminal association with a terrorist enterprise," in connection with al-Qaida. Finally, less than a month later, a random bird somehow managed to drop a "bit of baguette" into the machine, causing it to overheat and shut down.
The sheer number and variety of problems eventually led some in the scientific press to speculate that a force from the future or God himself was deliberately sabotaging the Large Hadron Collider to prevent it from unleashing a great catastrophe via its experiments.
However, since being turned back on in November, the LHC has performed "almost flawlessly," according to The Associated Press.
The latest energy achievement also kicks off what is to be the LHC's longest period of continual operation. CERN says it will remain on and accelerating for the next 18 to 24 months. By the end of 2010, however, it will be shut down for a short period of maintenance. And then again, in 2011, it will be turned off for a whole year to undergo more extensive repairs.
2010 AOL Inc. All Rights Reserved.
Friday, March 5, 2010
Dream Team Conclusion - Asteroid Did Kill the Dinosaurs
Traci Watson Contributor
AOL News
(March 4) -- For decades, scientists have debated exactly what kind of cataclysm was responsible for the extinction of the dinosaurs. Did a giant rock from outer space blast T. rex and his ilk off the face of the Earth? Or was a huge volcanic eruption to blame?
Now the jury is in -- maybe. In Friday's issue of the prestigious journal Science, a "dream team" of 41 researchers from 12 nations declares that the evidence points overwhelmingly to a mountain-sized asteroid that walloped the planet 65 million years ago. The monstrous boulder left an equally monstrous scar, a 120-mile-wide dimple known as the Chicxulub crater on the Mexican coast.
"We assessed the whole picture," says Kirk Johnson of the Denver Museum of Nature and Science. "The answer is quite simple. ... The Chicxulub crater really is the culprit."
An allosaurus skeleton at the Carnegie Museum of Natural History in Pittsburgh, Pa.
Andrew Rush, AP
What killed off Earth's dinosaurs and many other life forms 65 million years ago? An international research team has concluded it was an asteroid that hit Mexico.
The holdouts who downplay the asteroid's role are unconvinced.
"It's the same old story from them," says Norman MacLeod of the Natural History Museum in London, referring to the team that wrote the new paper. "The authors conveniently forget to mention critical data."
But MacLeod and another prominent doubter, Gerta Keller of Princeton University, don't dispute that a colossal space rock hit the Earth roughly 65 million years ago. And whether or not that led to the demise of the dinosaurs, new research is painting an increasingly detailed picture of the hellish conditions after the asteroid's arrival.
It would take a mighty rock to do in the mighty lizards known as dinosaurs, and on that count the Chicxulub asteroid fits the bill. It was big -- more than seven miles across, three times the width of Manhattan -- and it was moving fast -- 20 times the speed of a rifle bullet. When it hit, the explosion unleashed a billion times more energy than the atomic bomb dropped on Hiroshima, says Gareth Collins of Imperial College London.
In a paper published last year, Collins found that the asteroid in 30 seconds drilled an initial crater 19 miles deep, nearly penetrating the Earth's crust. Earthquakes of up to magnitude 11 -- 1,000 times more powerful than the recent Chilean earthquake -- shook the area, and tsunamis more than 300 feet high inundated nearby coasts. The asteroid that created the crater was more than seven miles wide and moved 20 times faster than a rifle bullet.
The impact was so violent that it melted and vaporized both the asteroid itself and the spot the asteroid hit. Within an hour, melted rock had splattered as far as northern Canada, says David Kring of the Lunar and Planetary Institute. An immense plume of vaporized and melted material burst through the atmosphere and into outer space. Within a few hours, tiny drops from that plume began raining down through the atmosphere all across the Earth's surface.
As they fell, these drops grew hotter, literally broiling the planet for several minutes, according to another 2009 study. Any exposed animal "is not going to do so well," says the University of Vienna's Tamara Goldin, one of the study's authors.
The combination of dust, soot and caustic chemicals filling the air blotted out the sun, Kring says. The sky close to the crater first glowed red then went pitch black. All over the globe, a biblical darkness fell, lasting perhaps a week, maybe nearly a year.
The darkness shut down photosynthesis, the process by which plants capture sunlight to grow. Huge swathes of forest died. Entire classes of animals perished.
But that's where the narrative gets disputed. The authors of the new study say that more than 60 percent of species went extinct, including most dinosaurs. MacLeod, though, says that dinosaurs were in decline for millions of years before the asteroid hit. He also wonders why, if the asteroid strike was such a doomsday event, some classes of species survived and even thrived.
Keller questions even more basic claims, such as the dating of the asteroid strike. She argues that the Chicxulub rock hammered Earth hundreds of thousands of years before the mass extinctions shown in the fossil record.
Just such arguments -- and media coverage of them -- are what prompted the scientists to publish their new paper, Goldin says. After ignoring Keller and other skeptics for many years, the pro-crater forces got so frustrated that they decided to put all the evidence together.
"It is almost impossible to change the skeptics' minds," Goldin concedes. "But we hope we can communicate to the scientific community and the public that this impact-induced environmental catastrophe did happen."
Filed under: Nation, World, Science
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2010 AOL Inc. All Rights Reserved.
AOL News
(March 4) -- For decades, scientists have debated exactly what kind of cataclysm was responsible for the extinction of the dinosaurs. Did a giant rock from outer space blast T. rex and his ilk off the face of the Earth? Or was a huge volcanic eruption to blame?
Now the jury is in -- maybe. In Friday's issue of the prestigious journal Science, a "dream team" of 41 researchers from 12 nations declares that the evidence points overwhelmingly to a mountain-sized asteroid that walloped the planet 65 million years ago. The monstrous boulder left an equally monstrous scar, a 120-mile-wide dimple known as the Chicxulub crater on the Mexican coast.
"We assessed the whole picture," says Kirk Johnson of the Denver Museum of Nature and Science. "The answer is quite simple. ... The Chicxulub crater really is the culprit."
An allosaurus skeleton at the Carnegie Museum of Natural History in Pittsburgh, Pa.
Andrew Rush, AP
What killed off Earth's dinosaurs and many other life forms 65 million years ago? An international research team has concluded it was an asteroid that hit Mexico.
The holdouts who downplay the asteroid's role are unconvinced.
"It's the same old story from them," says Norman MacLeod of the Natural History Museum in London, referring to the team that wrote the new paper. "The authors conveniently forget to mention critical data."
But MacLeod and another prominent doubter, Gerta Keller of Princeton University, don't dispute that a colossal space rock hit the Earth roughly 65 million years ago. And whether or not that led to the demise of the dinosaurs, new research is painting an increasingly detailed picture of the hellish conditions after the asteroid's arrival.
It would take a mighty rock to do in the mighty lizards known as dinosaurs, and on that count the Chicxulub asteroid fits the bill. It was big -- more than seven miles across, three times the width of Manhattan -- and it was moving fast -- 20 times the speed of a rifle bullet. When it hit, the explosion unleashed a billion times more energy than the atomic bomb dropped on Hiroshima, says Gareth Collins of Imperial College London.
In a paper published last year, Collins found that the asteroid in 30 seconds drilled an initial crater 19 miles deep, nearly penetrating the Earth's crust. Earthquakes of up to magnitude 11 -- 1,000 times more powerful than the recent Chilean earthquake -- shook the area, and tsunamis more than 300 feet high inundated nearby coasts. The asteroid that created the crater was more than seven miles wide and moved 20 times faster than a rifle bullet.
The impact was so violent that it melted and vaporized both the asteroid itself and the spot the asteroid hit. Within an hour, melted rock had splattered as far as northern Canada, says David Kring of the Lunar and Planetary Institute. An immense plume of vaporized and melted material burst through the atmosphere and into outer space. Within a few hours, tiny drops from that plume began raining down through the atmosphere all across the Earth's surface.
As they fell, these drops grew hotter, literally broiling the planet for several minutes, according to another 2009 study. Any exposed animal "is not going to do so well," says the University of Vienna's Tamara Goldin, one of the study's authors.
The combination of dust, soot and caustic chemicals filling the air blotted out the sun, Kring says. The sky close to the crater first glowed red then went pitch black. All over the globe, a biblical darkness fell, lasting perhaps a week, maybe nearly a year.
The darkness shut down photosynthesis, the process by which plants capture sunlight to grow. Huge swathes of forest died. Entire classes of animals perished.
But that's where the narrative gets disputed. The authors of the new study say that more than 60 percent of species went extinct, including most dinosaurs. MacLeod, though, says that dinosaurs were in decline for millions of years before the asteroid hit. He also wonders why, if the asteroid strike was such a doomsday event, some classes of species survived and even thrived.
Keller questions even more basic claims, such as the dating of the asteroid strike. She argues that the Chicxulub rock hammered Earth hundreds of thousands of years before the mass extinctions shown in the fossil record.
Just such arguments -- and media coverage of them -- are what prompted the scientists to publish their new paper, Goldin says. After ignoring Keller and other skeptics for many years, the pro-crater forces got so frustrated that they decided to put all the evidence together.
"It is almost impossible to change the skeptics' minds," Goldin concedes. "But we hope we can communicate to the scientific community and the public that this impact-induced environmental catastrophe did happen."
Filed under: Nation, World, Science
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