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January 7, 2007, 9:00 PM CT

Black Hole In Tiny 'Dwarf' Galaxy

Black Hole In Tiny 'Dwarf' Galaxy Dwarf galaxy, VCC128, at the center, and the enlargement at right shows a double nucleus that suggests the presence of a black hole.
Credit: NASA/Hubble Space Telescop
Astronomers have found evidence of a supermassive black hole at the heart of a dwarf elliptical galaxy about 54 million light years away from the Milky Way galaxy where Earth resides.

It is only the second time a supermassive black hole has been discerned in a dwarf galaxy, and only the third time that astronomers have observed a double nucleus at the heart of a galaxy, said Victor P. Debattista, a postdoctoral researcher in astronomy at the University of Washington.

The galaxy, called VCC128, lies in the Virgo Cluster and is about 1 percent the size of the Milky Way. All of its stars combined would equal 100 million to 1 billion of our suns, Debattista said.

"It's a very small galaxy, on the outskirts of the cluster," he said. "It is effectively the smallest galaxy in which there is a supermassive black hole".

Black holes lie at the center of many galaxies, and have gravitational fields so powerful that nothing - not even light - can escape. A supermassive black hole is so large that its mass equals anywhere between 100,000 and 10 billion of our suns.

Debattista is the lead author of a poster detailing the discovery being presented today at the American Astronomical Society national meeting in Seattle. Co-authors are Ignacio Ferreras of Kings College in London, Anna Pasquali of the Max-Planck-Institut für Astronomie in Germany, Anil Seth at the Harvard-Smithsonian Center for Astrophysics in Boston, Sven De Rijcke of the Universiteit Gent in Belgium, and Lorenzo Morelli of Pontificia Universidad Catolica in Chile. The work was funded by a grant from the National Science Foundation, a Brooks Prize Fellowship at the UW and the Fund for Scientific Research in Belgium.........

Posted by: Edwin      Read more         Source


January 7, 2007, 7:12 AM CT

A new way to spin up pulsars

A new way to spin up pulsars The progression of spiral formation in a supernova, which eventually results in a pulsar's spin.
A team of scientists using Oak Ridge National Laboratory supercomputers has discovered the first plausible explanation for a pulsar's spin that fits the observations made by astronomers. Anthony Mezzacappa of the Department of Energy lab's Physics Division and John Blondin of North Carolina State University explain their results in the Jan. 4 issue of the journal Nature. According to three-dimensional simulations they performed at the Leadership Computing Facility, located at ORNL, the spin of a pulsar is determined not by the spin of the original star, but by the shock wave created when the star's massive iron core collapses.

That shock wave is inherently unstable, a discovery the team made in 2002, and eventually becomes cigar-shaped instead of spherical. The instability creates two rotating flows-one in one direction directly below the shock wave and another, inner flow, that travels in the opposite direction and spins up the core.

"The stuff that's falling in toward the center, if it hits this shock wave that is not a sphere any more but a cigar-shaped surface, will be deflected," Mezzacappa said. "When you do this in 3-D, you find that you wind up with not only one flow, but two counterrotating flows".

The asymmetrical flows establish a "sloshing" motion that, in the complex 3-D models, accounts for the pulsars observed spin velocities from once every 15 to 300 milliseconds, which is much slower than previous models predicted.........

Posted by: Edwin      Read more         Source


December 28, 2006, 9:59 PM CT

Finding a Different Mars Underneath

Finding a Different Mars Underneath
Mars is showing scientists its older, craggier face buried beneath the surface, thanks to a pioneering sounding radar co-sponsored by NASA aboard the European Space Agency's Mars Express orbiter.

Observations by the first project to explore a planet by sounding radar strongly suggest that ancient impact craters lie buried beneath the smooth, low plains of Mars' northern hemisphere. The technique uses echoes of waves that have penetrated below the surface.

"It's almost like having X-ray vision," said Dr. Thomas R. Watters of the National Air and Space Museum's Center for Earth and Planetary Studies, Washington. "Besides finding previously unknown impact basins, we've also confirmed that some of the subtle topographic depressions mapped previously in the lowlands are related to impact features".

Studies of how Mars evolved aid understanding of early Earth. Some signs of the forces at work a few billion years ago are more evident on Mars because, on Earth, many of them have been obliterated during Earth's more active resurfacing by tectonic activity.

Watters and nine co-authors report the findings in the Dec. 14, 2006 issue of the journal Nature.

The researchers used the orbiter's Mars Advanced Radar for Subsurface and Ionospheric Sounding, which was provided to the European Mars mission by NASA and the Italian Space Agency. The instrument transmits radio waves that pass through the Martian surface and bounce off features in the subsurface with electrical properties that contrast with those of materials that buried them.........

Posted by: Edwin      Read more         Source


December 28, 2006, 9:49 PM CT

Challenges When Hawking Innovations

Challenges When Hawking Innovations
Hundreds of technology-transfer offices have popped up on campuses over the past 20 years to enable universities to facilitate the commercialization of innovations and discoveries pioneered by their professors. Licensing patents for the inventions is a commercial opportunity for universities, which hope to make money selling the intellectual property and to see faculty research make a tangible impact in the marketplace. While all the inventions might be equally genius, they aren't all equally valuable. The question for technology-transfer offices is: what will sell?

Daniel Elfenbein, assistant professor of organization and strategy at the Olin School of Business, found that the ease of selling intellectual property doesn't necessarily depend on whether the innovation has received patent protection.

Elfenbein examined the timing of licensing with respect to whether a patent for the invention had already been applied for or granted by the U.S. Patent and Trademark Office, a process that typically takes multiple years.

"Getting intellectual property protection does increase the likelihood of finding a buyer - that's true on average," Elfenbein said. "However, if you are an established professor with a great reputation, receiving a patent grant isn't as necessary in order to sell the technology. But professors who are still relatively young, or who haven't attained high status yet, benefit from receiving this intellectual property protection from the patent office".........

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December 28, 2006, 9:32 PM CT

What Killed and Preserved Juvenile Fossil Plesiosaur

What Killed and Preserved Juvenile Fossil Plesiosaur A mother and juvenile plesiosaur probably looked like this artist's rendering.
Credit: Nicolle Rager, National Science Foundatio
Amid 70-mile-an-hour winds and freezing Antarctic conditions, an American-Argentine research team has recovered the well-preserved fossil skeleton of a juvenile plesiosaur--a marine reptile that swam the waters of the Southern Ocean roughly 70 million years ago.

The fossil remains represent one of the most-complete plesiosaur skeletons ever found and is believed to be the best-articulated fossil skeleton ever recovered from Antarctica. The creature would have inhabited Antarctic waters during a period when the Earth and oceans were far warmer than they are today.

James E. Martin, curator of vertebrate paleontology and coordinator of the paleontology program at the South Dakota School of Mines and Technology's Museum of Geology, announced recently the plesiosaur bones will be unveiled at the museum on Dec.13, 2006.

The long-necked, diamond-finned plesiosaurs are probably most familiar as the legendary inhabitants of Scotland's Loch Ness, eventhough scientific evidence indicates the marine carnivores have been extinct for millions of years. But when the creatures were alive, their paddle-like fins would have allowed them to "fly through the water" in a motion very similar to modern-day penguins.

Martin, an expert on fossil marine reptiles, co-led the 2005 expedition to Antarctica that recovered the plesiosaur. Judd Case, of Eastern Washington University, and Marcelo Reguero of the Museo de La Plata, Argentina, were also co- leaders.........

Posted by: Nora      Read more         Source


December 27, 2006, 5:10 AM CT

Tools To Improve Classroom Learning

Tools To Improve Classroom Learning
When instructors at Bronx-area community colleges applied for a National Science Foundation (NSF) grant to study how students think about fundamental concepts of calculus, they hoped to gain a better understanding of how college students learn mathematics. During the 4-year project, the teacher-scientists integrated ongoing research theories with classroom teaching. As a result, their project has evolved into a tool for helping students reason their way through complex calculus.

The scientists observed that when students are actively engaged in the learning process, they are more likely to sort out the logic behind mathematical problems. A give-and-take method allows the students to voice their fears about the subject, express misconceptions, and participate in open discussions to reach a solution. Using an online, peer-evaluated teaching-research journal, the teacher-scientists give updates on their progress and share best practices and procedures. They invite other mathematics teachers and instructors to document their experiences and successes.

"The journal project contributes to NSF's goal to create an online network of learning environments and resources for science, technology, engineering, and mathematics education at all levels," said Lee L. Zia, program director for NSF's Division of Undergraduate Education. "Through a relatively easy mechanism to share best practices with the local community, the journal stimulates and supports research on learning, which is one of NSF's objectives".........

Posted by: Nora      Read more         Source


December 27, 2006, 4:59 AM CT

Super-stable Glass May Aid Drug Delivery

Super-stable Glass May Aid Drug Delivery A type of glass created by researchers at the University of Wisconsin-Madison
Credit: University of Wisconsin-Madison
Look at your window - not out it, but at it. Though the window glass looks clear, if you could peer inside the pane you would see a surprising molecular mess, with tiny particles jumbled together any which way.

Now, scientists at the University of Wisconsin-Madison have developed a new glass-making technique that eliminates some of that mess. With the new technology, described in a study in the Dec. 8 issue of Science, they created a novel glass that is stronger and more stable than glass made in traditional ways. Though not suitable to replace everyday products like window panes or eyeglasses, this new glass may allow pharmaceutical companies the opportunity to explore previously unusable drug compounds.

When considered at the molecular level, most solid materials can be described as either crystals or glasses, explains lead author Mark Ediger, a UW-Madison chemistry professor. The difference lies in the degree of internal organization of their constituent molecules.

"A crystal is like toy soldiers all lined up marching together," Ediger says. "A glass is a teenager's room, with stuff packed in everywhere."

Just as levels of messiness can range from cluttered to chaotic, levels of molecular disorder can vary between different types of glass. Glasses composed of more organized molecules are more stable and durable, while glasses with haphazard molecular assemblies are less stable and may degrade over time.........

Posted by: John      Read more         Source


December 26, 2006, 6:31 PM CT

Developing Invisibility

Developing Invisibility
The theorists who first created the mathematics that describe the behavior of the recently announced "invisibility cloak" have revealed a new analysis that may extend the current cloak's powers, enabling it to hide even actively radiating objects like a flashlight or cell phone.

Allan Greenleaf, professor of mathematics at the University of Rochester, working with colleagues around the globe, has announced a mathematical theory that predicts some strange goings on inside the cloak-and that what happens inside is crucial to the cloak's effectiveness.

In October, David R. Smith, associate professor of electrical and computer engineering at Duke University, led a team that used a circular cloaking device to successfully bend microwaves around a copper disk as if the disk were invisible. In 2003, however, Greenleaf and colleagues had already developed the mathematics of invisibility.

"We were working on improving the mathematics behind tumor detection," says Greenleaf. "In the final section to one paper, we spelled out a worst-case scenario where a tumor could be undetectable. We then wrote a couple of additional articles describing when this could happen. At the time, we didn't think further about it because it seemed extremely unlikely that any tumor would be covered with the necessary material to be hidden that way".........

Posted by: John      Read more         Source


December 26, 2006, 6:13 PM CT

Western Wildfires And Atlantic Ocean

Western Wildfires And Atlantic Ocean
Western U.S. wildfires are likely to increase in the coming decades, as per a new tree-ring study led by the University of Comahue in Argentina and involving the University of Colorado at Boulder that links episodic fire outbreaks in the past five centuries with periods of warming sea surface temperatures in the North Atlantic.

States like Washington, Oregon, California, Colorado, New Mexico, Arizona and South Dakota all had an increased prevalence of wildfires in recent centuries when a phenomenon known as the Atlantic Multi-Decadal Oscillation -- similar but longer in duration than the better known El Nino-Southern Oscillation -- periodically shifted from a cool to a warm mode that lasted roughly 60 years each time, said the study authors.

Warmer waters in the North Atlantic correspond with episodes of drought and subsequent fires in the West as shown by fire scars in annual tree rings studied by the researchers, said Thomas Kitzberger of the University of Comahue, who led the study with scientists from CU-Boulder, the University of Arizona, the U.S. Forest Service and Rocky Mountain Tree-Ring Research Inc., a private lab in Fort Collins, Colo.

Kitzberger, who received his doctorate from CU-Boulder in 1994 under co-author and CU-Boulder geography Professor Thomas Veblen, said the North Atlantic warming trend, coupled with warming temperatures and the earlier onset of spring in the West, poses "an increased hazard for wildfires that may continue for decades." The paper was published the week of Dec. 25 in the Proceedings of the National Academy of Sciences.........

Posted by: Nora      Read more         Source


December 23, 2006, 10:51 AM CT

invisible Electronics

invisible Electronics
Imagine a car windshield that displays a map to your destination, military goggles with targets and instructions displayed right before a soldier's eyes or a billboard that doubles as a window.

Only in science fiction you say? Northwestern University scientists report that by combining organic and inorganic materials they have produced transparent, high-performance transistors that can be assembled inexpensively on both glass and plastics.

The results of this breakthrough, which brings such futuristic high-quality displays closer to reality, were reported in the November 2006 issue of the journal Nature Materials.

Scientists have long worked on developing new types of displays powered by electronics without visible wires. But, until now, no one was able to develop materials for transistors that could be "invisible" while still maintaining a high level of performance.

"Our development provides new strategies for creating transparent electronics," said Tobin J. Marks, the Vladimir N. Ipatieff Research Professor in Chemistry in the Weinberg College of Arts and Sciences at Northwestern and professor of materials science and engineering, who led the research. "You can imagine a variety of applications for new electronics that haven't been possible previously -- imagine displays of text or images that would seem to be floating in space".........

Posted by: John      Read more         Source


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