Rapidly Inflating Volcano Creates Growing Mystery
|10:00:32 PM, Monday, October 24, 2011|
"Should anyone ever decide to make a show called "CSI: Geology," a group of scientists studying a mysterious and rapidly inflating South American volcano have got the perfect storyline.
Researchers from several universities are essentially working as geological detectives, using a suite of tools to piece together the restive peak's past in order to understand what it is doing now, and better diagnose what may lie ahead.
It's a mystery they've yet to solve.
Uturuncu is a nearly 20,000-foot-high (6,000 meters) volcano in southwest Bolivia. Scientists recently discovered the volcano is inflating with astonishing speed.
"I call this 'volcano forensics,' because we're using so many different techniques to understand this phenomenon," said Oregon State University professor Shan de Silva, a volcanologist on the research team.
Researchers realized about five years ago that the area below and around Uturuncu is steadily rising — blowing up like a giant balloon under a wide disc of land some 43 miles (70 kilometers) across. Satellite data revealed the region was inflating by 1 to 2 centimeters (less than an inch) per year and had been doing so for at least 20 years, when satellite observations began.
"It's one of the fastest uplifting volcanic areas on Earth," de Silva told OurAmazingPlanet."What we're trying to do is understand why there is this rapid inflation, and from there we'll try to understand what it's going to lead to."
The peak is perched like a party hat at the center of the inflating area. "It's very circular. It's like a big bull's-eye," said Jonathan Perkins, a graduate student at the University of California, Santa Cruz, who recently presented work on the mountain at this year's Geological Society of America meeting in Minneapolis.
Scientists figured out from the inflation rate that the pocket of magma beneath the volcano was growing by about 27 cubic feet (1 cubic meter) per second.
"That's about 10 times faster than the standard rate of magma chamber growth you see for large volcanic systems," Perkins told OurAmazingPlanet.
However, no need to flee just yet, the scientists said.
"It's not a volcano that we think is going to erupt at any moment, but it certainly is interesting, because the area was thought to be essentially dead," de Silva said..."
Up to 20 Million Tons of Debris from Japan’s Tsunami Moving Toward Hawaii
|9:57:16 PM, Monday, October 24, 2011|
"Some 5 to 20 million tons of debris--furniture, fishing boats, refrigerators--sucked into the Pacific Ocean in the wake of Japan's March 11 earthquake and tsunami are moving rapidly across the Pacific. Researchers from the University of Hawaii tracking the wreckage estimate it could approach the U.S. West Coast in the next three years, the UK Daily Mail reports.
"We have a rough estimate of 5 to 20 million tons of debris coming from Japan," University of Hawaii researcher Jan Hafner told Hawaii's ABC affiliate KITV.
Crew members from the Russian training ship the STS Pallada "spotted the debris 2,000 miles from Japan," last month after passing the Midway islands, the Mail wrote. "They saw some pieces of furniture, some appliances, anything that can float, and they picked up a fishing boat," said Hafner. The boat was 20-feet long, and was painted with the word "Fukushima." "That's actually our first confirmed report of tsunami debris," Hafner told KITV..."
NASA, Japan Release Improved Topographic Map of Earth
|1:55:31 AM, Monday, October 24, 2011|
"NASA and Japan released a significantly improved version of the most complete digital topographic map of Earth on Oct. 17, produced with detailed measurements from NASA's Terra spacecraft.
The map, known as a global digital elevation model, was created from images collected by the Japanese Advanced Spaceborne Thermal Emission and Reflection Radiometer, or ASTER, instrument aboard Terra. So-called stereo-pair images are produced by merging two slightly offset two-dimensional images to create the three-dimensional effect of depth. The first version of the map was released by NASA and Japan's Ministry of Economy, Trade and Industry (METI) in June 2009.
"The ASTER global digital elevation model was already the most complete, consistent global topographic map in the world," said Woody Turner, ASTER program scientist at NASA Headquarters in Washington. "With these enhancements, its resolution is in many respects comparable to the U.S. data from NASA's Shuttle Radar Topography Mission, while covering more of the globe."
The improved version of the map adds 260,000 additional stereo-pair images to improve coverage. It features improved spatial resolution, increased horizontal and vertical accuracy, more realistic coverage over water bodies and the ability to identify lakes as small as 0.6 miles (1 kilometer) in diameter. The map is available online to users everywhere at no cost.
"This updated version of the ASTER global digital elevation model provides civilian users with the highest-resolution global topography data available," said Mike Abrams, ASTER science team leader at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "These data can be used for a broad range of applications, from planning highways and protecting lands with cultural or environmental significance, to searching for natural resources."
The ASTER data cover 99 percent of Earth's landmass and span from 83 degrees north latitude to 83 degrees south. Each elevation measurement point in the data is 98 feet (30 meters) apart.
NASA and METI are jointly contributing the data for the ASTER topographic map to the Group on Earth Observations, an international partnership headquartered at the World Meteorological Organization in Geneva, Switzerland, for use in its Global Earth Observation System of Systems. This "system of systems" is a collaborative, international effort to share and integrate Earth observation data from many different instruments and systems to help monitor and forecast global environmental changes..."
Planet-Sized Object as Cool as Earth Revealed in Record-Breaking Photo
|1:04:21 AM, Monday, October 24, 2011|
"The photo of a nearby star and its orbiting companion -- whose temperature is like a hot summer day in Arizona -- will be presented by Penn State Associate Professor of Astronomy and Astrophysics Kevin Luhman during the Signposts of Planets conference at NASA's Goddard Space Flight Center on Oct. 20, 2011.
A paper describing the discovery will be published in the Astrophysical Journal.
"This planet-like companion is the coldest object ever directly photographed outside our solar system," said Luhman, who led the discovery team. "Its mass is about the same as many of the known extra-solar planets -- about six to nine times the mass of Jupiter -- but in other ways it is more like a star. Essentially, what we have found is a very small star with an atmospheric temperature about cool as the Earth's."Luhman classifies this object as a "brown dwarf," an object that formed just like a star out of a massive cloud of dust and gas. But the mass that a brown dwarf accumulates is not enough to ignite thermonuclear reactions in its core, resulting in a failed star that is very cool. In the case of the new brown dwarf, the scientists have gauged the temperature of its surface to be between 80 and 160 degrees Fahrenheit -- possibly as cool as a human.
Ever since brown dwarfs first were discovered in 1995, astronomers have been trying to find new record holders for the coldest brown dwarfs because these objects are valuable as laboratories for studying the atmospheres of planets with Earth-like temperatures outside our solar system.
Astronomers have named the brown dwarf "WD 0806-661 B" because it is the orbiting companion of an object named "WD 0806-661" -- the "white dwarf" core of a star that was like the Sun until its outer layers were expelled into space during the final phase of its evolution. "The distance of this white dwarf from the Sun is 63 light years, which is very near our solar system compared with most stars in our galaxy," Luhman said.
"The distance of this white dwarf from its brown-dwarf companion is 2500 astronomical units (AU) -- about 2500 times the distance between the Earth and the Sun, so its orbit is very large as compared with the orbits of planets, which form within a disk of dust swirling close around a newborn star," said Adam Burgasser at the University of California, San Diego, a member of the discovery team. Because it has such a large orbit, the astronomers say this companion most probably was born in the same manner as binary stars, which are known to be separated as far apart as this pair, while remaining gravitationally bound to each other.
Luhman and his colleagues presented this new candidate for the coldest known brown dwarf in a paper published in spring 2011, and they now have confirmed its record-setting cool temperature in a new paper that will be published in the Astrophysical Journal.
To make their discovery, Luhman and his colleagues searched through infrared images of over six hundred stars near our solar system. They compared images of nearby stars taken a few years apart, searching for any faint points of light that showed the same motion across the sky as the targeted star. "Objects with cool temperatures like the Earth are brightest at infrared wavelengths," Luhman said. "We used NASA's Spitzer Space Telescope because it is the most sensitive infrared telescope available."
Luhman and his team discovered the brown dwarf WD 0806-661 B moving in tandem with the white dwarf WD 0806-661 in two Spitzer images taken in 2004 and 2009. The images, which together show the movement of the objects, are available online (http://science.psu.edu/alert/photos/research-photos/astro/Luhman-moving-labels.gif). "This animation is a fun illustration of our technique because it resembles the method used to discovery Pluto in our own solar system," Luhman said..."
Spiral Arms Hint at Presence of Planets: High Resolution Image of Young Star With Circumstellar Disks Verifies Predictions
|3:52:03 AM, Sunday, October 23, 2011|
"A new image of the disk of gas and dust around a sun-like star has spiral-arm-like structures. These features may provide clues to the presence of embedded but as-yet-unseen planets.
"Detailed computer simulations have shown us that the gravitational pull of a planet inside a circumstellar disk can perturb gas and dust, creating spiral arms. Now, for the first time, we're seeing these features," said Carol Grady, a National Science Foundation (NSF)-supported astronomer with Eureka Scientific, Inc.
The newly imaged disk surrounds SAO 206462, a star located about 456 light-years away in the constellation Lupus. Astronomers estimate that the system is only about 9 million years old. The gas-rich disk spans some 14 billion miles, which is more than twice the size of Pluto's orbit in our own solar system."The surprise," said Grady, "was that we caught a glimpse of this stage of planet formation. This is a relatively short-lived phase."
A near-infrared image from the National Astronomical Observatory of Japan shows a pair of spiral features arcing along the outer disk. Theoretical models show that a single embedded planet may produce a spiral arm on each side of a disk. The structures around SAO 206462 do not form a matched pair, suggesting the presence of two unseen worlds, one for each arm. However, the research team cautions that processes unrelated to planets may also give rise to these structures.
"What we're finding is that once these systems reach ages of a few million years, their disks begin to show a wealth of structure--rings, divots, gaps and now spiral features," said John Wisniewski, a collaborator at the University of Washington in Seattle. "Many of these structures could be caused by planets within the disks."
Grady's research is part of the Strategic Exploration of Exoplanets and Disks with Subaru (SEEDS), a five-year-long near-infrared study of young stars and their surrounding dust disks using the Subaru Telescope atop Mauna Kea in Hawaii. The international consortium of researchers now includes more than 100 scientists at 25 institutions.
"These arm-like structures have been predicted by models, but have never before been seen," said Maria Womack, program director for the division of Astronomical Sciences at NSF. "It is the first observation of spiral arms in a circumstellar disk, and an important test for models of planetary formation.""
Last Universal Common Ancestor More Complex Than Previously Thought
|3:42:30 AM, Sunday, October 23, 2011|
"Scientists call it LUCA, the Last Universal Common Ancestor, but they don't know much about this great-grandparent of all living things. Many believe LUCA was little more than a crude assemblage of molecular parts, a chemical soup out of which evolution gradually constructed more complex forms. Some scientists still debate whether it was even a cell.
New evidence suggests that LUCA was a sophisticated organism after all, with a complex structure recognizable as a cell, researchers report. Their study appears in the journal Biology Direct.
The study builds on several years of research into a once-overlooked feature of microbial cells, a region with a high concentration of polyphosphate, a type of energy currency in cells. Researchers report that this polyphosphate storage site actually represents the first known universal organelle, a structure once thought to be absent from bacteria and their distantly related microbial cousins, the archaea. This organelle, the evidence indicates, is present in the three domains of life: bacteria, archaea and eukaryotes (plants, animals, fungi, algae and everything else).
The existence of an organelle in bacteria goes against the traditional definition of these organisms, said University of Illinois crop sciences professor Manfredo Seufferheld, who led the study.
"It was a dogma of microbiology that organelles weren't present in bacteria," he said. But in 2003 in a paper in the Journal of Biological Chemistry, Seufferheld and colleagues showed that the polyphosphate storage structure in bacteria (they analyzed an agrobacterium) was physically, chemically and functionally the same as an organelle called an acidocalcisome (uh-SID-oh-KAL-sih-zohm) found in many single-celled eukaryotes.
Their findings, the authors wrote, "suggest that acidocalcisomes arose before the prokaryotic (bacterial) and eukaryotic lineages diverged." The new study suggests that the origins of the organelle are even more ancient.
The study tracks the evolutionary history of a protein enzyme (called a vacuolar proton pyrophosphatase, or V-H+PPase) that is common in the acidocalcisomes of eukaryotic and bacterial cells. (Archaea also contain the enzyme and a structure with the same physical and chemical properties as an acidocalcisome, the researchers report.)
By comparing the sequences of the V-H+PPase genes from hundreds of organisms representing the three domains of life, the team constructed a "family tree" that showed how different versions of the enzyme in different organisms were related. That tree was similar in broad detail to the universal tree of life created from an analysis of hundreds of genes. This indicates, the researchers said, that the V-H+PPase enzyme and the acidocalcisome it serves are very ancient, dating back to the LUCA, before the three main branches of the tree of life appeared.
"There are many possible scenarios that could explain this, but the best, the most parsimonious, the most likely would be that you had already the enzyme even before diversification started on Earth," said study co-author Gustavo Caetano-Anollés, a professor of crop sciences and an affiliate of the Institute for Genomic Biology at Illinois. "The protein was there to begin with and was then inherited into all emerging lineages."
"This is the only organelle to our knowledge now that is common to eukaryotes, that is common to bacteria and that is most likely common to archaea," Seufferheld said. "It is the only one that is universal."
The study lends support to a hypothesis that LUCA may have been more complex even than the simplest organisms alive today, said James Whitfield, a professor of entomology at Illinois and a co-author on the study..."
Animal Transplants Coming 'Soon'
|3:37:01 AM, Sunday, October 23, 2011|
"Are pigs about to migrate from the dinner table to the operating table?
Using animals as a source of organs for transplantation into humans was once one of medicine's next big things - a solution to transplant waiting lists.
However, there have been problems with rejection - and recently stem cells have been grabbing the spotlight.
But some researchers are now saying that transplants from animals "could soon become a reality", but not necessarily as originally expected.
There is still a pressing need for organs. In the UK there are 8,000 people on the waiting list - three die every day.
Several technologies are trying to meet the demand. In August, a patient from London was the first in the UK to have his heart replaced with a mechanical one while stem cells have been used for simple structures such as the windpipe.
However, using stem cells to build more complicated organs such as a heart is a long way off and mechanical body parts are used in the short term before an actual transplant.
Using animals as a source - known as "xenotransplantation" - is another potential solution.
Pigs have been used as a source of heart valves, which control the flow of blood around the heart. Here the pig cells are chemically stripped away and when the remaining structure is transplanted, human cells grow around it.
Stripping away the living material would not work for most transplants - nobody would want the heart that did not beat.
However, that living material has a big problem, namely rejection. The human immune system attacks the pig tissue, which it recognises as foreign.
Dr David Cooper from the University of Pittsburgh Medical Centre is one of a group of researchers arguing in the Lancet that the problems with organ rejection are being overcome.
Some pigs - GTKO pigs - have been genetically modified. They no longer produce a pig protein, galactosyltransferase, which the immune system would have attacked.
The authors say that this kind of rejection is "not the main cause of graft failure", however, "other issues have become more prominent"..."
Hawaii Astronomer Captures Image of Forming Planet
|8:27:36 PM, Thursday, October 20, 2011|
“Astronomers have captured the first direct image of a planet being born.
Adam Kraus, of the University of Hawaii's Institute for Astronomy, said the planet is being formed out of dust and gas circling a 2-milion-year-old star about 450 light years from Earth.
The planet itself, based on scientific models of how planets form, is estimated to have started taking shape about 50,000 to 100,000 years ago.
Called LkCa 15 b, it's the youngest planet ever observed. The previous record holder was about five times older.
Kraus and his colleague, Michael Ireland from Macquarie University and the Australian Astronomical Observatory, used Keck telescopes on Mauna Kea to find the planet.
"We're catching this object at the perfect time. We see this young star, it has a disc around it that planets are probably forming out of and we see something right in the middle of a gap in the disc," Kraus said in a telephone interview.
Kraus presented the discovery Wednesday at NASA's Goddard Space Flight Center in Maryland. Kraus and Ireland's research paper on the discovery is due to appear in The Astrophysical Journal.
Observing planets while they're forming can help scientists answer questions like whether planets form early in the life of a star or later, and whether they form relatively close to stars or farther away.
Planets can change orbits after forming, so it's difficult to answer such questions by studying older planets.
"These very basic questions of when and where are best answered when you can actually see the planet forming, as the process is happening right now," Kraus said.
Other planets may also be forming around the same star. Kraus said he'll continue to observe the star and hopefully will see other planets if there are in fact more.
Scientists hadn't been able to see such young planets before because the bright light of the stars they're orbiting outshines them.
Kraus and Ireland used two techniques to overcome this obstacle.
One method, which is also used by other astronomers, was to change the shape of their mirror to remove light distortions created by the Earth's atmosphere.
The other, unique method they used was to put masks over most of the telescope mirror. The combination of these two techniques allowed the astronomers to obtain high-resolution images that let them see the faint planet next to the bright star.
The astronomers found the planet while surveying 150 young dusty stars. This led to a more concentrated study of a dozen stars.
The star LkCa 15 — the planet is named after its star — was the team's second target. They immediately knew they were seeing something new, so they gathered more data on the star a year later.”
Qaddafi Is Killed as Libyan Forces Take Surt
|3:41:01 PM, Thursday, October 20, 2011|
"TRIPOLI, Libya — Col. Muammar el-Qaddafi, the former Libyan strongman who fled into hiding after an armed uprising toppled his regime two months ago, met a violent death Thursday in the hands of rebel fighters who stormed his final stronghold in his Mediterranean hometown Surt.
Al Jazeera television showed gruesome footage of what appeared to be Colonel Qaddafi, alive but bloody, being dragged around by armed men in Surt. The television also broadcast a separate clip of his half-naked body, with lifeless open eyes and an apparent gunshot wound to the side of the head, as jubilant fighters fired automatic weapons in the air.
Conflicting accounts quickly emerged about whether Colonel Qaddafi was executed by his captors, died from gunshot wounds sustained in a firefight, was mortally wounded in a NATO bomb blast or bled to death in an ambulance. But the images broadcast by Al Jazeera punctuated an emphatic and violent ending to his four decades as a ruthless and bombastic autocrat who had basked in his reputation as the self-styled king of kings of Africa.
“We have been waiting for this moment for a long time. Muammar Qaddafi has been killed,” Mahmoud Jibril, the prime minister of the Transitional National Council, the interim government, told a news conference in Tripoli. Mahmoud Shammam, the council’s chief spokesman, called it “the day of real liberation. We were serious about giving him a fair trial. It seems God has some other wish."
Libyan television also reported that one of Colonel Qaddafi’s feared fugitive sons, Muatassim, was killed in Surt, showing what it said was his lifeless bloodied body on a hospital gurney. There were also unconfirmed accounts that another feared son, Seif al-Islam, had been captured and possibly wounded.
In Washington, President Obama said in a televised statement that the death of Colonel Qaddafi signaled the start of a new chapter for Libya. “We can definitely say that the Qaddafi regime has come to an end,” he said. “The dark shadow of tyranny has been lifted and with this enormous promise the Libyan people now have a great responsibility to build an inclusive and tolerant and democratic Libya that stands as the ultimate rebuke to Qaddafi’s dictatorship.”
Libyans rejoiced as news of his death spread. Car horns blared and residents poured into the streets in giddy disbelief in Tripoli and in the eastern city of Benghazi, where the rebellion against Colonel Qaddafi began in February and escalated into the most violent of the Arab Spring uprisings.
“I can’t believe it’s over,” said Tahir Busrewil, a 26 year-old tourist industry worker in Tripoli who was imprisoned and tortured earlier this year, and had spent the past few weeks working with a militia to detain pro-Qaddafi loyalists. “Oh the relief! I never felt that happy about somebody being dead.” Walid Fakany, an anti-Qaddafi fighter from the Western mountain town of Rujban, who joined in the celebrations in Tripoli, said: “We can breathe, we can finally rest. Then we can move forward.”
Fighters from Misurata, the port city that suffered enormously at the hands of Colonel Qaddafi’s forces during the uprising, were in possession of Colonel Qaddafi’s body and took it to their hometown, where it was kept in a private house but moved a few hours later to an undisclosed location because hundreds of people had converged to see it, Misurata residents said.
Holly Picket, a freelance photojournalist working in Surt, reported in a twitter feed that she had seen Colonel Qaddafi’s body in an ambulance headed for Misurata, along with 10 fighters inside with him. It was unclear from her posting whether he was dead. “From the side door, I could see a bare chest with bullet wound and a bloody hand. He was wearing gold-colored pants,” she tweeted.
Within an hour of the news of Colonel Qaddafi’s death, the Arab twittersphere lit up with gleeful comments, many of them hinting at a similar fate awaiting other Arab dictators — most notably President Ali Abdullah Saleh of Yemen and President Bashar al-Assad of Syria. One of them read: “Ben Ali escaped, Mubarak is in jail, Qaddafi was killed. Which fate do you prefer, Ali Abdullah Saleh? You can consult with Bashar.” Another was more direct: “Bashar al-Assad, how do you feel today?” ..."
Fiery Volcano Offers Geologic Glimpse Into Land That Time Forgot
|4:06:53 AM, Thursday, October 20, 2011|
"The first scientists to witness exploding rock and molten lava from a deep sea volcano, seen during a 2009 expedition, report that the eruption was near a tear in Earth's crust that is mimicking the birth of a subduction zone.
Scientists on the expedition collected boninite, a rare, chemically distinct lava that accompanies the formation of Earth's subduction zones.
Nobody has ever collected fresh boninite and scientists never had the opportunity to monitor its eruption before, said Joseph Resing, University of Washington oceanographer and lead author of an online article on the findings in Nature Geoscience. Earth's current subduction zones are continually evolving but most formed 5 million to 200 million years ago. Scientists have only been able to study boninite collected from long-dead, relic volcanos millions of years old.
Resing was chief scientist on the expedition, funded by the National Oceanic and Atmospheric Administration and the National Science Foundation, that pinpointed the location of the West Mata volcano, erupting 4,000 feet (1,200 meters) below the surface in the Southwest Pacific Ocean.
"Everything about the eruption itself -- how fast, how intense, the ratio of lava to explosive fragments, the amount and composition of gas released -- is new to us," said co-author Kenneth Rubin, University of Hawaii geologist. "Plus, having a young, fresh occurrence of this very rare rock type to study gives us the opportunity to examine subtle chemical and mineralogical variations in a pristine specimen."
At subduction zones the oceanic crust on one tectonic plate slides beneath another, producing abundant volcanism and contributing heat, gases and mineral-laden fluids to ocean waters. Scientists have long studied the impact of subduction zones on geological and geochemical cycles. To puzzle out how subduction zones form and evolve they study inactive contemporary marine volcanos that do not produce boninite and they collect and study boninite lavas collected on land and examine cores collected from the deep sea.
"West Mata lies above the subducting Pacific plate and is part of the rapidly expanding Lau Basin, which is bounded by Samoa, Tonga and Fiji," Resing said. "The large bend at the northern end of the Tonga trench produces a tear in the Pacific plate and creates unusual lavas that usually only form at very young subduction zones."
Conditions are right for boninite to form, there's lots of seawater released from subducting rock that mixes into relatively shallow mantle that has previously melted, causing the mantle to remelt at high temperatures. Boninite lavas are believed to be among the hottest from volcanos that erupt on Earth..."
Detroit Police Impound Booty Lounge Strip Club on Wheels
|3:36:12 AM, Thursday, October 20, 2011|
"Tailgating is an important part of going to see a sports event in person, and in the city of Detroit, that pastime also includes something called the Booty Lounge. The Booty Lounge is a low-rent strip-club on wheels, and it has been a somewhat shady part of the game-day experience in Detroit since 2005.
Owners of the mobile strip club were likely hoping for a big payday thanks to a Lions appearance on the NFL's Monday Night Football, but instead, the bus was impounded by Detroit Police. Detroit's NBC affiliate reports that the bus was towed way because it was parked illegally, the driver didn't have a commercial license and the vehicle wasn't inspected by the Michigan Department of Transportation. The fuzz reportedly weren't targeting the rolling tribute, but the bus recently came under fire after a local TV station uncovered the goings-on inside the bus.
The Booty Lounge will reportedly be cleared to exit the impound once it provides proof of inspection, but we're getting the feeling that this tailgater is going to be sitting out a quite few more games."
Dark Matter Mystery Deepens
|1:06:31 AM, Thursday, October 20, 2011|
"Like all galaxies, our Milky Way is home to a strange substance called dark matter. Dark matter is invisible, betraying its presence only through its gravitational pull. Without dark matter holding them together, our galaxy's speedy stars would fly off in all directions. The nature of dark matter is a mystery -- a mystery that a new study has only deepened.
"After completing this study, we know less about dark matter than we did before," said lead author Matt Walker, a Hubble Fellow at the Harvard-Smithsonian Center for Astrophysics.
The standard cosmological model describes a universe dominated by dark energy and dark matter. Most astronomers assume that dark matter consists of "cold" (i.e. slow-moving) exotic particles that clump together gravitationally. Over time these dark matter clumps grow and attract normal matter, forming the galaxies we see today.
Cosmologists use powerful computers to simulate this process. Their simulations show that dark matter should be densely packed in the centers of galaxies. Instead, new measurements of two dwarf galaxies show that they contain a smooth distribution of dark matter. This suggests that the standard cosmological model may be wrong.
"Our measurements contradict a basic prediction about the structure of cold dark matter in dwarf galaxies. Unless or until theorists can modify that prediction, cold dark matter is inconsistent with our observational data," Walker stated.Dwarf galaxies are composed of up to 99 percent dark matter and only one percent normal matter like stars. This disparity makes dwarf galaxies ideal targets for astronomers seeking to understand dark matter.
Walker and his co-author Jorge Peñarrubia (University of Cambridge, UK) analyzed the dark matter distribution in two Milky Way neighbors: the Fornax and Sculptor dwarf galaxies. These galaxies hold one million to 10 million stars, compared to about 400 billion in our galaxy. The team measured the locations, speeds and basic chemical compositions of 1500 to 2500 stars..."
U.S. Drug Policy Would Be Imposed Globally By New House Bill
|12:21:06 AM, Thursday, October 20, 2011|
"The House Judiciary Committee passed a bill yesterday that would make it a federal crime for U.S. residents to discuss or plan activities on foreign soil that, if carried out in the U.S., would violate the Controlled Substances Act (CSA) -- even if the planned activities are legal in the countries where they're carried out. H.R. 313, the "Drug Trafficking Safe Harbor Elimination Act of 2011," is sponsored by Judiciary Committee Chairman Rep. Lamar Smith (R-Texas), and allows prosecutors to bring conspiracy charges against anyone who discusses, plans or advises someone else to engage in any activity that violates the CSA, the massive federal law that prohibits drugs like marijuana and strictly regulates prescription medication.
"Under this bill, if a young couple plans a wedding in Amsterdam, and as part of the wedding, they plan to buy the bridal party some marijuana, they would be subject to prosecution," said Bill Piper, director of national affairs for the Drug Policy Alliance, which advocates for reforming the country's drug laws. "The strange thing is that the purchase of and smoking the marijuana while you're there wouldn't be illegal. But this law would make planning the wedding from the U.S. a federal crime."
The law could also potentially affect academics and medical professionals. For example, a U.S. doctor who works with overseas doctors or government officials on needle exchange programs could be subject to criminal prosecution. A U.S. resident who advises someone in another country on how to grow marijuana or how to run a medical marijuana dispensary would also be in violation of the new law, even if medical marijuana is legal in the country where the recipient of the advice resides. If interpreted broadly enough, a prosecutor could possibly even charge doctors, academics and policymakers from contributing their expertise to additional experiments like the drug decriminalization project Portugal, which has successfully reduced drug crime, addiction and overdose deaths.
The Controlled Substances Act also regulates the distribution of prescription drugs, so something as simple as emailing a friend vacationing in Tijuana some suggestions on where to buy prescription medication over the counter could subject a U.S. resident to criminal prosecution. "It could even be something like advising them where to buy cold medicine overseas that they'd have to show I.D. to get here in the U.S.," Piper says.
Civil libertarian attorney and author Harvey Silverglate says the bill raises several concerns. "Just when you think you can't get any more cynical, a bill like this comes along. I mean, it just sounds like an abomination. First, there's no intuitive reason for an American to think that planning an activity that's perfectly legal in another country would have any effect on America," Silverglate says. "So we're getting further away from the common law tradition that laws should be intuitive, and should include a mens rea component. Second, this is just an act of shameless cultural and legal imperialism. It's just outrageous."
Conspiracy laws in general are problematic when applied to the drug war. They give prosecutors extraordinary discretion to charge minor players, such as girlfriends or young siblings, with the crimes committed by major drug distributors. They're also easier convictions to win, and can allow prosecutors to navigate around restrictions like statutes of limitations, so long as the old offense can be loosely linked to a newer one. The Smith bill would expand those powers. Under the Amsterdam wedding scenario, anyone who participated in the planning of the wedding with knowledge of the planned pot purchase would be guilty of conspiracy, even if their particular role was limited to buying flowers or booking the hotel.
The law is a reaction to a 2007 case in which the 11th Circuit U.S. Court of Appeals threw out the convictions of two men who planned the transfer of cocaine from a Colombian drug cartel to a Saudi prince for distribution in Europe. Though the men planned the transaction from Miami, the court found that because the cocaine never reached the U.S. and was never intended to reach the U.S., the men hadn't committed any crime against the United States..."
NASA's Spitzer Detects Comet Storm in Nearby Solar System
|12:13:22 AM, Thursday, October 20, 2011|
"NASA's Spitzer Space Telescope has detected signs of icy bodies raining down in an alien solar system. The downpour resembles our own solar system several billion years ago during a period known as the "Late Heavy Bombardment," which may have brought water and other life-forming ingredients to Earth.
During this epoch, comets and other frosty objects that were flung from the outer solar system pummeled the inner planets. The barrage scarred our moon and produced large amounts of dust.
Now Spitzer has spotted a band of dust around a nearby bright star in the northern sky called Eta Corvi that strongly matches the contents of an obliterated giant comet. This dust is located close enough to Eta Corvi that Earth-like worlds could exist, suggesting a collision took place between a planet and one or more comets. The Eta Corvi system is approximately one billion years old, which researchers think is about the right age for such a hailstorm.
"We believe we have direct evidence for an ongoing Late Heavy Bombardment in the nearby star system Eta Corvi, occurring about the same time as in our solar system," said Carey Lisse, senior research scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., and lead author of a paper detailing the findings. The findings will be published in the Astrophysical Journal. Lisse presented the results at the Signposts of Planets meeting at NASA's Goddard Space Flight Center in Greenbelt, Md., on Oct. 19.
Astronomers used Spitzer's infrared detectors to analyze the light coming from the dust around Eta Corvi. Certain chemical fingerprints were observed, including water ice, organics and rock, which indicate a giant comet source.
The light signature emitted by the dust around Eta Corvi also resembles the Almahata Sitta meteorite, which fell to Earth in fragments across Sudan in 2008. The similarities between the meteorite and the object obliterated in Eta Corvi imply a common birthplace in their respective solar systems.
A second, more massive ring of colder dust located at the far edge of the Eta Corvi system seems like the proper environment for a reservoir of cometary bodies. This bright ring, discovered in 2005, looms at about 150 times the distance from Eta Corvi as Earth is from the sun. Our solar system has a similar region, known as the Kuiper Belt, where icy and rocky leftovers from planet formation linger. The new Spitzer data suggest that the Almahata Sitta meteorite may have originated in our own Kuiper Belt..."
Prehistoric Speedway: Super-Sized Muscle Made Twin-Horned Dinosaur a Speedster
|2:37:29 AM, Wednesday, October 19, 2011|
"A meat-eating dinosaur that terrorized its plant-eating neighbours in South America was a lot deadlier than first thought, a University of Alberta researcher has found.
Carnotaurus was a seven-metre-long predator with a huge tail muscle that U of A paleontology graduate student Scott Persons says made it one of the fastest running hunters of its time.
A close examination of the tail bones of Carnotaurus showed its caudofemoralis muscle had a tendon that attached to its upper leg bones. Flexing this muscle pulled the legs backwards and gave Carnotaurus more power and speed in every step.
In earlier research, Persons found a similar tail-muscle and leg-power combination in the iconic predator Tyrannosaurus rex. Up until Persons published that paper, many dinosaur researchers thought T. rex's huge tail might have simply served as a teeter-totter-like counterweight to its huge, heavy head.
Persons' examination of the tail of Carnotaurus showed that along its length were pairs of tall rib-like bones that interlocked with the next pair in line. Using 3-D computer models, Persons recreated the tail muscles of Carnotaurus. He found that the unusual tail ribs supported a huge caudofemoralis muscle. The interlocked bone structure along the dinosaur's tail did present one drawback: the tail was rigid, making it difficult for the hunter to make quick, fluid turns. Persons says that what Carnotaurus gave up in maneuverability, it made up for in straight ahead speed. For its size, Carnotaurus had the largest caudofemoralis muscle of any known animal, living or extinct.
Persons published these findings in PLoS ONE on Oct.14, with supervisor Philip Currie, a paleontology professor at the U of A."
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