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June 10, 2006, 7:48 PM CT

Circuit Board Materials May Like It Hot

Circuit Board Materials May Like It Hot
Electrical circuits may act differently in Arizona than they do in Alaska--potentially affecting the performance of computers and other electronics. A new technique identifies and quantifies an important cause of this temperature sensitivity.

Researchers at the National Institute of Standards and Technology (NIST) and DuPont Electronic Technologies (Research Triangle Park, N.C.) have demonstrated a nondestructive method for measuring how temperature affects the electrical properties of three common circuit board materials (ceramic, polymer and glass). The work, described at a recent conference,* provides manufacturers with an accurate technique for measuring high-frequency electrical properties of substrates without cutting up the material--enabling faster, less expensive and easier testing--as well as a tool for designing circuits and substrates with improved performance.

NIST has been working with ceramic and printed-wiring board manufacturers for five years to develop the technique. They previously have used the method to measure changes in electrical properties as substrates are subjected to different electromagnetic frequencies. The work is important to the electronics industry because the performance of electrical circuits depends in part on the electrical properties of the substrate.........

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June 10, 2006, 6:51 PM CT

Ancient caldera in Apollinaris Patera

Ancient caldera in Apollinaris Patera
Credits: ESA/DLR/FU Berlin (G. Neukum)

See high resolution image

Apollinaris Patera is an ancient shield volcano measuring approximately 180 by 280 kilometres at its base and rising to a maximum of 5 kilometres above the surrounding terrain. Shield volcanos are large volcanic structures with gently sloping flanks. The caldera of Apollinaris Patera takes the form of a large crater approximately 80 kilometres in diameter. In this false-colour image, north is to the right. The image also shows the terrain partly covered by thin, diffuse clouds indicated by bluish-tinted areas.

This false-colour image was captured on 26 October 2004 by the High-Resolution Stereo Camera (HRSC) onboard the ESA spacecraft Mars Express with a ground resolution of approximately 11.1 metres per pixel.........

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June 9, 2006, 0:13 AM CT

Why Space Is Dusty

Why Space Is Dusty
Massive star supernovae have been major "dust factories" ever since the first generations of stars formed several hundred million years after the Big Bang, as per an international study published in Science Express today.

The scientific team trained their telescopes on Supernova 2003gd, which exploded in the NGC 628 spiral galaxy 30 million light-years from Earth. The light from the 2003gd first reached Earth on March 17, 2003. At its brightest, it could be seen in an amateur astronomer's telescope. While a number of supernovae are discovered each year, this particular one stood out because it was relatively nearby and could be followed for a longer-than-usual time by the specialized infrared detectors of the Spitzer Space Telescope, and by a spectrograph on the Gemini North telescope. "2003gd is, quite literally, the smoking gun," says Doug Welch, professor, physics & astronomy at McMaster University, and one of 17 astronomers involved in the study. "These carbon and silicon dust particles which form from the supernovae blast make possible the a number of generations of high-mass stars and all the heavy elements they produce. These are elements which make up the bulk of everything around us on Earth, including you and me."

Welch and co-author Geoff Clayton of Louisiana State University, visited the Gemini North telescope in Hawaii to take spectra of ancient massive star supernovae in their hunt for the formation of dust.........

Posted by: Edwin      Permalink         Source


June 7, 2006, 11:51 PM CT

Forming Super-earths By Ultraviolet Stripping

Forming Super-earths By Ultraviolet Stripping Image courtesy of rogers-md.net
A new explanation for forming "super-Earths" suggests that they are more likely to be found orbiting red dwarf stars--the most abundant type of star--than gas giant planets like Jupiter and Saturn. The theory, by Dr. Alan Boss of the Carnegie Institution's Department of Terrestrial Magnetism, describes a mechanism whereby UV radiation from a nearby massive star strips off a planet's gaseous envelope exposing a super-Earth. The work, reported in the June 10, 2006, Astrophysical Journal (Letters), explains recent extrasolar planet discoveries by the microlensing method.

Super-Earths have masses that range between those of Earth and Neptune but have unknown compositions. "Of the 300 stars closest to the Sun, at least 230 are red dwarf stars, with masses less than half that of our Sun," Boss says. "Because nearby stars are the easiest places to look for other Earth-like planets, it is important to try to predict what types of planetary systems they might have, and that means trying to figure out how their planets can form."

Recently, evidence was presented for perhaps the lowest-mass planet found to date in orbit around a main sequence star like the Sun. It was found by an international consortium of astronomers via a microlensing event, where a foreground star amplifies the light from a much more distant star by bending the light of the background star in our direction, an effect predicted by Einstein. In addition, they observed a secondary brightening as well, consistent with the presence of a roughly 5.5-Earth-mass planet orbiting the foreground star at a distance similar to the asteroid belt in our Solar System. While the identity of the foreground star is unknown, it is most likely a red dwarf (M dwarf) star. Evidence for microlensing by a 13-Earth-mass planet around another red dwarf was subsequently presented.........

Posted by: Edwin      Permalink         Source


June 7, 2006, 0:02 AM CT

Young Supernova Remnants Not Dusty Enough

Young Supernova Remnants Not Dusty Enough

One of the youngest supernova remnants known, a glowing red ball of dust created by the explosion 1,000 years ago of a supermassive star in a nearby galaxy, the Small Magellanic Cloud, exhibits the same problem as exploding stars in our own galaxy: too little dust.

Recent measurements by University of California, Berkeley, astronomers using infrared cameras aboard NASA's Spitzer Space Telescope show, at most, one-hundredth the amount of dust predicted by current theories of core-collapse supernovae, barely the mass of the planets in the solar system.

The discrepancy presents a challenge to researchers trying to understand the origins of stars in the early universe, because dust produced primarily from exploding stars is believed to seed the formation of new-generation stars. While remnants of supermassive exploding stars in the Milky Way galaxy also show less dust than predicted, astronomers had hoped that supernovae in the less-evolved Small Magellanic Cloud would accord more with their models.

"Most of the prior work was focused only on our galaxy because we didn't have enough resolution to look further away into other galaxies," said astrophysicist Snezana Stanimirovic, a research associate at UC Berkeley. "But with Spitzer, we can obtain really high resolution observations of the Small Magellanic Cloud, which is 200,000 light years away. Because supernovae in the Small Magellanic Cloud experience conditions similar to those we expect for early galaxies, this is a unique test of dust formation in the early universe".........

Posted by: Edwin      Permalink         Source


June 6, 2006, 11:43 PM CT

Supercomputers To Transform Science

Supercomputers To Transform Science
New insights into the structure of space and time, climate modeling, and the design of novel drugs, are but a few of the many research areas that will be transformed by the installation of three supercomputers at the University of Bristol.

At peak performance the multi-million pound high performance computers (HPCs) will carry out over 13 trillion calculations per second. That is equivalent to the entire population of the world working simultaneously on hand-held calculators for about three hours.

"This initiative puts Bristol at the forefront of high performance computing", said Professor David May, Head of Computer Science. "The HPC impact will be enormous - right across all disciplines - turning data into knowledge. It will influence both research and teaching. Universities that understand this will be the most competitive in the 21st century".

The University today announced the award of the contract to install the computers to a consortium led by ClusterVision, working with IBM and ClearSpeed Technology. The largest of the three HPCs will be one of the fastest University research computers in the UK, and is expected to be one of the top 100 computers of its type in the world.

Dr David Newbold, physicist, explained how the new HPC cluster will allow the University's physicists to be amongst the first to examine results from the Large Hadron Collider, the world's largest particle collider which is set to provide new insights into the structure of space and time and the origin of mass.........

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June 5, 2006, 9:09 PM CT

Galaxy Evolution In Cyber Universe

Galaxy Evolution In Cyber Universe 13.4 Billion Years After the Big Bang
Researchers at the University of Chicago have bolstered the case for a popular scenario of the big bang theory that neatly explains the arrangement of galaxies throughout the universe. Their supercomputer simulation shows how dark matter, an invisible material of unknown composition, herded luminous matter in the universe from its initial smooth state into the cosmic web of galaxies and galaxy clusters that populate the universe.

Prior studies by other scientists had already verified the main features of this scenario, called the cold dark matter model. The Chicago team further extended this work by comparing the results of their supercomputer simulations to the newest, most detailed astronomical observations available today. They found an excellent fit, and they did so without basing their simulations on a lot of complex assumptions.

"The model we use is really, really simple," said Andrey Kravtsov, Associate Professor in Astronomy & Astrophysics. "We want to see how well this framework can do with a minimum number of assumptions".

A paper co-authored by Kravtsov, Charlie Conroy and Risa Wechsler describing these findings would be reported in the June 20 issue of the Astrophysical Journal. The research was funded by a grant from the National Science Foundation, with additional support from the National Aeronautics and Space Administration.........

Posted by: Edwin      Permalink         Source


June 4, 2006, 1:39 PM CT

Big astronomy project for Chile

Big astronomy project for Chile
With new support for additional federal funding, the largest ground-based astronomy project is unfolding in the high Chilean desert.

The $1 billion Atacama Large Millimeter Array, or ALMA, will look as far back in time as 1 billion years after the Big Bang, producing a kind of astronomical baby book for researchers to peruse.

When completed about 2012, the array will allow astronomers to examine planet and star formation, the formation of early galaxies and galaxy clusters and the detection of organic and other molecules in space.

Formal planning for the project started in the 1990s with the Charlottesville-based National Radio Astronomy Observatory. Since then, it has been beset by a changing global economy and ballooning costs, issues peculiar to the site located 16,500 feet above sea level and international government bureaucracies. New partners have signed on, but the U.S. share is now $566 million.........

Posted by: Edwin      Permalink         Source


June 3, 2006, 6:48 PM CT

Eardrum Could Lead To Tiny Microphones

Eardrum Could Lead To Tiny Microphones
Being able to hear the smallest of noises is a matter of life or death for many insects, but for the scientists studying their hearing systems understanding how insect ears can be so sensitive could lead to new microphones able to capture and analyse extremely faint sounds.

A multidisciplinary team at the University of Bristol have used funding from the Biotechnology and Biological Sciences Research Council (BBSRC) to explore the workings of the 'ears' of a locust. These are micrometre thick membranes with complex and varying structural properties. The thickness of the membrane varies at different points and this affects how it responds to sounds - and in the case of ambient noise the team have discovered the membrane oscillates by only a few nanometres. The thickness of a human hair is about 80,000 nanometres across.

Professor Daniel Robert is the research leader at Bristol: "We have found that different sound frequencies elicit very different mechanical responses in the locust hearing system. By studying these tiny nanoscale movements and understanding how sound waves are turned into mechanical responses we may be able to develop microphones based on the functions of natural hearing. These could detect very faint sounds and analyse their frequency, something that current microphones cannot pick up".........

Posted by: John      Permalink         Source


June 3, 2006, 1:33 PM CT

Make your gadgets unstealable

Make your gadgets unstealable
When I finally bought an iPod, it was after 2 years of waiting for the "right" model to come along. But my troubles failed to cease - for along came the fear of getting my precious one nicked. There isn't a truly comprehensive insurance scheme available for portable electronics as yet, so we recommend that you take a look at Datadots for some solace. So what are Datadots? The Datadots DNA kit contains a bunch of tiny dots suspended in adhesive which you smear on your beloved gadgets. Each dot within the kit contains the same unique serial number which you register at the Datadots site. The idea is that if the device is stolen and is recovered by police, they can trace it back to you.

Wondering what's the use of Datadots once the device is already stolen? For one, the police can definitely tell if the gadget is stolen. If you are a persistent gluer, you can also stick the dots in different places on the gadget (though it is recommended to smear the glue mostly on the gadget innards, to keep it looking pretty). A major deterrent for thieves is that they will end up with a very ugly gadget if they try scraping off all the dots. The glue also contains warning stickers to highlight that the gadget has been marked against theft.

Datadots are also being used by car manufacturers such as Audi, BMW and Ford Australia to reduce car thefts, and by several corporations and leading manufacturers as well. Check out the Datadots global website for further information.........

Posted by: John      Permalink         Source


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