Saturday, January 31, 2009

Quality of Stradivarius Violins Linked to Wood Treatment

Scientists at Texas A&M University have analyzed Stradivarius and Guarneri violins and found a brutal chemical treatment of the wood is responsible for their unique sound quality.

Obtaining minute wood samples from restorers of these instruments (“no easy trick and it took a lot of begging to get them”), they burned the wood slivers to ash to identify the individual chemicals used via advanced spectroscopic analysis. Numerous chemical compounds were found in the wood including borax, fluorides, chromium and iron salts. Borax alone has a long history of preservative use, dating back to Egyptian mummification and insecticide.

Stradivari and Guarneri aggressively treated the wood for their instruments for purposes of preservation, especially protection against the widespread problem of worms eating away at the wood. First theorized to be the reason in 1976, this heavy chemical treatment is directly responsible for the unmatched modern sound quality of these stringed instruments.

Antonio Stradivari produced about 1200 instruments in his lifetime, of which about half survive. His contemporary Guarneri del Gesu had trouble selling his own instruments, but they are now considered of equal quality and value as Stradivari's.

These results were published in the current issue of the journal Public Library of Science, subsequent to a preliminary analysis published in Nature in 2006.

Source: ScienceDaily

Friday, January 30, 2009

Particles Detected Underground Tied to Upper Atmosphere

Scientists at the UK’s National Centre for Atmospheric Science (NCAS) and the Science and Technology Facilities Council (STFC) have discovered that particles detected deep underground correlate to weather events in the Earth's upper atmosphere.

Collaborating with the US-based Main Injector Neutrino Oscillation Search (MINOS) project at Fermilab, scientists analyzed data collected from an abandoned iron-ore mine in Minnesota. They found a remarkably close correlation between subatomic particles named muons detected underground and the temperature of the stratosphere. Cosmic rays naturally decay upon entering the atmosphere, producing a muon as a daughter product. A rise in temperature means an expansion of the atmosphere, with fewer impacts destroying cosmic rays and leaving them to decay and produce muons.

Also suprising was a correlation with sudden and intermittent increases in stratosphere temperature (as much as 40°C) occurring during winter months. This weather event, known as Sudden Stratospheric Warming, has long been regarded as unpredictable but now can be identified by sudden increases in the levels of muons detected.

Climate data has previously only been available via weather balloons and satelites, but these findings open a new avenue for ground-based meteorological study.

These results were published in a recent edition of Geophysical Research Letters.

Source: ScienceDaily

Thursday, January 29, 2009

New Method for Producing Hydrogen Discovered

Scientists at Penn State University and Virginia Commonwealth University have discovered a new method for producing hydrogen gas that relies on molecular geometry rather than electronic interactions.

The team found that water molecules (H2O) will bind to sites located on the surface of an aluminum cluster if one of the sites acts as a Lewis acid (receives an electron) and the other acts as a Lewis base (donates an electron). The oxygen in the water will bind to the Lewis-acid site while the Lewis-base site disassociates the hydrogen. If two such Lewis-base sites are close enough, the two hydrogen atoms will join to form hydrogen gas (H2).

Previous research indicated that interactions between atoms relied solely upon electronic properties, that is, the exchange of electrons. This discovery indicates that it is the geometry of the molecular structure in these aluminum clusters that causes this process, a method that could open up a whole new area of research based on atomic arrangement.

This process also occurs at room temperature without the need for added energy, which is the typical method for the production of hydrogen gas, also known as hydrolysis. The aluminum clusters can be reclaimed and recycled for continuous use, which could lead to new, more energy-efficient methods of industrial and commercial hydrogen production.

These results were published in the January 23rd edition of Science.

Source: ScienceDaily

Wednesday, January 28, 2009

Electronic Switch Formed from Single Gold Atoms

A scientist at the University of Groningen has developed a method for creating a nanoscale electronic switch composed of only two single gold atoms.

The process creates a so-called break junction, which involves bending a thin gold wire under very controlled conditions almost to the breaking point. Further bending moves the ends just apart, enough to separate the atoms but not enough to produce a permanent fracture; as the ends are moved back, the material connection reforms. By repeating this process many times, the atoms on each side of the gap reorganize themselves into a regular formation, much like "carefully stacked pyramids of billiard balls with a single atom at the apex." This manufacturing process produces a contact composed of two single gold atoms that can be broken by a 0.1-nm movement to separate them.

Current electronics technology is expected to approach a barrier to miniaturization within the next ten years, as the function of transistors reaches a fundamental physical limit. Atomic-scale nanotechnology is being examined as a method to further miniaturize electronic components by manipulating individual atoms.

These results are part of a doctoral thesis recently defended at the University of Groningen.

Source: ScienceDaily

Tuesday, January 27, 2009

New Catfish Species Is Missing Link Between Families

A species of South American catfish newly discovered by scientists at the American Museum of Natural History and the Universidad Central de Venezuela appears to be a missing link between two modern families of fish.

Native to the Río Orinoco basin, the Lithogenes wahari shares physical traits with two other families of South American catfish. It has bony protective plates on its head and tail, similar to the Loricariidae family of fully armored catfish, and it also has a specialized pelvic fin that allows it to "walk" out of the water and push its way across land, similar to the Astroblepidae family of climbing catfish local to the Andes.

These shared characteristics between families suggest a common ancestry for these fishes, most likely located upland of the Orinoco and Amazon rather than the lowlands. Discovered some 20 years ago, original specimens were poorly preserved and not easily identified and classified. More recent specimens used for closer examination were collected from the Río Cuao, mostly plucked from the rocks by hand.

These results were published in a recent edition of American Museum Novitates (no website).

Source: ScienceDaily

Monday, January 26, 2009

Rare Annular Eclipse Seen Today

A rare annular solar eclipse occurred today that was visible in parts of the southeastern Pacific and Asia, with a partial eclipse visible to a wider range from Africa to Australia.

A solar eclipse occurs when the Moon moves between the Sun and the Earth, obscuring the sunlight. When the Moon is at a further distance from the Earth, its shape cannot completely cover that of the Sun, resulting in a ring-like crown known as an annular eclipse.

According to NASA, the track of this eclipse ran from the Indian Ocean across Indonesia and into the Philippines on Monday from 0606 GMT to 0952 GMT. A partial eclipse was visible to parts of southern Africa, southern India, southeast Asia and Australia. The next annular eclipse will not occur until 2010.

Source: Yahoo!

Sunday, January 25, 2009

Major New Fault Discovered in Eastern Arkansas

Scientists at the Arkansas Earthquake Center at the University of Arkansas at Little Rock have discovered a major, previously unknown fault in Arkansas that could trigger up to a magnitude 7.0 earthquake.

The new fault is near the town of Marianna in eastern Arkansas, about 100 miles east of Little Rock. It was indicated by stretches of fine sand with fertile soil, the result of liquefied sand bubbling up through underground vents. Ground radar and samples confirmed the existence of the fault, which likely formed within the past 5000 years. This fault is separate from the New Madrid Seismic Zone, an area stretching south into Arkansas from New Madrid, Missouri. This zone is a major fault line and was responsible for the widely destructive New Madrid earthquakes of 1811 and 1812, estimated to be around magnitude 8.0.

Researchers have expressed concerns over natural gas pipelines and other industrial conduits crossing this fault. This infrastructure is not required to have the more robust safety features as similar equipment in earthquake-prone southern California.

These results were presented on January 21st at a luncheon at the University of Arkansas Clinton School of Public Service.

Source: Yahoo!; Photo: Wikipedia

Saturday, January 24, 2009

New Marine Animals Discovered in Tasmanian Ocean

A joint US-Australian team of scientists from the California Institute of Technology and the Commonwealth Scientific and Industrial Research Organisation (CSIRO) has discovered previously unknown species of marine animals while exploring the deep waters off the coast of Tasmania.

The new animals found include "a bizarre carnivorous sea squirt [ascidian], sea spiders and giant sponges, and previously unknown marine communities dominated by gooseneck barnacles and millions of round, purple-spotted sea anemones." The team also found vast fossil coral fields dating back more than 10,000 years, from which samples could reveal ancient climate data.

The team used a submersible robot named Jason to venture into a previously unexplored area known as the Tasman Fracture Zone. This zone is a
rift in the Earth's crust that drops a sheer two kilometers to end at 4000 meters below the ocean's surface and is part of a protected marine reserve. The team also found evidence of the coral reef system dying, possibly as a result of the warming of ocean temperatures.

These results were published recently by the CSIRO Wealth from Oceans Flagship.

Source: ScienceDaily; Photo: Yahoo!

Friday, January 23, 2009

New Energy-Efficient Water Purification Process Developed

A scientist at Yale University has developed a new energy-efficient technology for drawing fresh water from nonpotable water sources.

Using a process called "forward osmosis," the system exploits the natural tendency of water to diffuse through a semipermeable membrane. It draws pure water away from its contaminants into a solution of concentrated salts, which are then easily removed by a low heat treatment. The system requires only about one-tenth the electrical energy used by traditional desalinization techniques. Yale University is commercializing this desalinization technology through a private company called Oasys.

Another similar technology is being developed into what is called an "osmotic heat engine" to more efficiently generate electricity using low-temperature heat sources. In a process called pressure-retarded osmosis, a solution is held under high pressure while water moves into the solution via osmosis. The pressure of the expanding volume of solution is then released through a turbine to generate electrical energy. The costs of producing electricity via this method can be competitive, as industrial waste heat can be used to fuel the process.

These results were published in the December issue of Environmental Science & Technology.

Source: ScienceDaily; Photo: Yale University

Thursday, January 22, 2009

New Family of Antibacterial Agents Discovered

Scientists at the University of Kiel have identified a new family of antimicrobial proteins that could be used to fight bacteria growing resistant to current antibacterial treatments.

Called macins, this new family includes the protein identified as hydramacin, a derivative obtained from the tiny freshwater animals Hydra. Other members of this family include two antimicrobial compounds previously discovered in leeches, with all these proteins similar to a superfamily known to exist in scorpion venom.

Laboratory tests have shown hydramacin to be extremely effective at killing both Gram-positive and Gram-negative bacteria, and sharing virtually no similarity with other commonly used antibacterial proteins. Hydramacin also proved effective at killing drug-resistant strains such as Klebsiella oxytoca, an infectious agent commonly found in hospitals.

These results were published in a recent issue of the Journal of Biological Chemistry.

Photo: ScienceDaily

Wednesday, January 21, 2009

Methane Belch on Mars Hints at Possible Life

Using Earth-based telescopes, researchers at NASA's Goddard Space Flight Center have confirmed that in the late summer of 2003, almost 21,000 tons of methane gas was released from localized areas on the western hemisphere of Mars.

A finding of extraterrestrial methane is significant because the gas is associated with life here on Earth, either as byproducts of digestion or decaying biomatter. As a waste product of life processes, it may also serve as a food source for other forms of life. With past studies finding no regular methane content in the Martian atmosphere, the sudden presence and quick dispersion of the gas could indicate an organic origin.

Similar methane appearances are found in some parts of Earth's oceans as decaying life on the sea floor releases a "belch" of gas. Other sources of methane are the presence of microbial life, possibly living in or beneath the Martian soil. Methane-producing microbes have been found in extreme Earth environments such as Arctic soil and volcanic vents.

Nonorganic sources of methane are also possible, involving volcanic processes or the mixture of water, carbon dioxide and other chemicals. Trapped underground, these gasses could be released through surface fissures as the pressure increases.

These results were published online in the January 15th edition of Science.

Photo: Yahoo!

Tuesday, January 20, 2009

Warburg Theory of Cancer Origin Confirmed

Researchers at Boston College and Washington University School of Medicine have found evidence that supports the theoretical origin of cancerous cells first proposed by Otto H. Warburg in 1924.

The Warburg theory of cancer proposed defects in the mitochondria, the metabolic "power plant" for the cell, as the cause of mutations and cancerous growth. Scientists have now identified a cellular lipid called cardiolipin that is used by the mitochondria in its normal function. Abnormalities in the quantity or composition of cardiolipin have been correlated with all types of cancerous tumors, as well as the energy-producing capacity of the cell.

A noted German biochemist, Warburg first proposed in 1924 that the cause of cancer was mutation or injury to a cell's mitochondria, thereby leading to irreversible damage and significant reductions in cellular metabolism. Warburg's work earned him the 1931 Nobel Prize for Medicine.

These results were published in the December edition of the Journal of Lipid Research.

Source: ScienceDaily; Photo: Wikipedia

Monday, January 19, 2009

Centuries-Long Climate Record Reconstructed from Coral

Scientists at the Woods Hole Oceanographic Institution have reconstructed a 218-year temperature record of the North Atlantic by analyzing brain coral.

A wide-ranging pressure phenomenon known as the North Atlantic Oscillation (NAO) affects the climate of North America, Europe and North Africa as well as the ocean between. Precise NAO data has always been difficult to obtain, as land-based measurements do not always capture its greater oceanic behavior. However, corals are slow-growing and have long life spans, and contain annual growth layers much like rings in a tree that depend upon seawater temperature. By sampling these oceanic corals, a month-by-month record of the NAO was recalculated for the previous 218 years.

Knowledge of the NAO has an impact on industries such as shipping, fishing, coastal management and hydroelectric power generation. The researchers did confirm that the variability of the NAO decade-to-decade during the late twentieth century was larger and with greater swings of temperature than previous centuries, suggesting that human industrialization is impacting the stability of the NAO.

Whether the NAO swings positive (warmer) or negative (cooler) over the decades has not been affected by human activity. Instead, the variability within those periods has increased, leading to stronger storms during positive cycles and weaker weather during negative cycles.

These results were published in the December issue of Nature Geoscience.

Photo: ScienceDaily

Sunday, January 18, 2009

Fossil Feces Provides Insight into Prehistoric Ecosystem

A team of researchers from the University of Adelaide, University of Otago and the New Zealand Department of Conservation has used fossilized feces of extinct giant birds to gather details about their prehistoric ecosystem.

Technically known as coprolites, more than 1500 samples of the fossilized feces were collected across New Zealand, mostly from four different extinct moa species, a giant flightless bird similar to the modern emu. DNA analysis was performed on the coprolite samples, some up to 15 centimeters in length, and details were extracted from of leaf fragments and plant seeds that made up the moa's diet and the environment in which it lived.

More than half the plants found in the moa's diets were under 30 centimeters tall, suggesting the moa were low grazers instead of feeding on tall trees and shrubs as previously believed. Birds play a role in ecosystem development by spreading undigested plant seeds in their feces. Many of the plant species identified in the moa's feces are now either threatened or rare, suggesting that the extinction of this bird impacted the ability for these plants to disperse and reproduce.

New Zealand presents an idea case for a study like this because elsewhere the now-extinct species disappeared too long ago. The moa are believed to have been hunted to extinction as recently as 1500 AD by the native Maori tribes.

These findings were published in a recent edition of Quaternary Science Reviews (no website).

Photo: ScienceDaily

Saturday, January 17, 2009

New Brain Area Developed in Primates for Small Motor Skills

Scientists at the University of Pittsburgh School of Medicine and Pittsburgh's Veterans Affairs Medical Center have identified a new area of the primate brain that evolved to enable the use of tools and other small, fine motor skills.

Most animals' primary motor cortex of the brain controls all movements indirectly via the pathways through the spinal cord. However, in human and higher primate brains researchers discovered another area located just outside the motor cortex that consists of specialized corticomotoneuronal cells. These cells control spinal cord motor neurons directly, specifically the neurons responsible for muscle movement in the shoulder, arm and hand.

The spinal neural structure is much the same in most vertebrates, but these corticomotoneuronal cells permit human and other primates brains to bypass the limitations imposed by greater spinal cord pathways and control these muscles directly. This allows the development of fine motor control necessary for the use of tools, throwing a ball or playing musical instruments.

Also discovered in this study is that these corticomotoneuronal cells are not present at birth but instead develop during the first months of life and become mature at about two years of age. The growth and progress of an infant's early motor skills is due to the establishment of these connections.

These results were published recently in an online edition of the Proceedings of the National Academy of Sciences.

Photo: LiveScience

Friday, January 16, 2009

Rapid Evolution of Many Species Due to Humans

A study at the University of California, Santa Cruz has shown that human sports hunting and fishing has forced changes in size and reproduction of many species as much as 300% faster than would occur naturally.

Researchers reviewed 34 previous studies stretching back two decades that tracked 29 different species across 40 different geographic systems. They found that human influences such as hunting and fishing have produced game animals 20% smaller than previous generations, and the age at which they first reproduce is 25% earlier than previous generations. In effect, humans act as "super-predators" on other species, dominating their natural evolutionary track.

That species can change due to human influence is not a new concept; the entire industry of animal husbandry consists of human-bred species. What scientists found remarkable in this study is the speed at which human predation can modify native wild species. These changes are found to occur 50% faster than those brought about by pollution, loss of habitat or introduction of foreign species. The study found changes in animals as small as fish and snails and as large as caribou and bighorn sheep.

Whereas a wolf may prey upon 20 other species, humans essentially prey upon hundreds of thousands. And whereas a wolf will prey upon the smaller and weaker individuals, advancing the natural selection of prey species, humans select the largest and strongest, forcing species' evolution in the opposite direction.

These results were published on January 12th online edition of the Proceedings of the National Academy of Sciences.

Photo: LiveScience

Thursday, January 15, 2009

Formation of Andes Acted as "Species Pump"

A researcher at Gothenburg University’s Department of Plant and Environmental Sciences has proposed a new theory of the Andes mountain range acting as a driving force for the massive biodiversity of life located in South America.

Using DNA analysis of hundreds of South American plant and animal species, this scientist was able to piece together common ancestors, and when and where evolving life separated into distinct species. A strong connection was identified between the increase in geographic speciation and the uplift of the Andes mountains beginning some 23 million years ago. The result of this mountain range formation was a "species pump" that increased the biodiversity and spread of species across the continent and into Central America.

The Andes are formed by the subduction of the Nazca tectonic plate beneath the South American plate. The vertical rise of these mountains not only created microclimates and environments that contributed to species diversification, it also forced the retreat and elimination of Lago Pebas, a great inland sea in the middle of South America, which acted as a barrier to species movement across the continent.

These results are part of a doctoral thesis defended on November 28th at Gothenburg University.

Source: ScienceDaily; Photo: Wikipedia

Wednesday, January 14, 2009

Human Brains Recognize Chemical Communication

Researchers at Rice University have demonstrated that the human brain recognizes and responds to other human chemical signals as a form of personal communication.

Women volunteers were exposed to various scent samples, one of which was the sweat of sexually aroused men. When the volunteers' brains were examined under functional magnetic resonance imaging (fMRI), they were found to process the scent in several parts of the brain, including the right fusiform region, the right orbitofrontal cortex and the right hypothalamus. Neither the fusiform region nor the orbitofrontal cortex is known to be associated with sexual behavior.

Known as chemosensory communication, scientists have long known that many animals communicate via chemical scent. This research shows that humans also communicate information at some level using an olfactory basis. More than a simple stimulus-response, the human brain was shown to react to the scent holistically instead of merely as a straightforward sexual signal.

This data was published in the December 31st issue of the Journal of Neuroscience.

Photo: ScienceDaily

Tuesday, January 13, 2009

Cheating Ants Detected and Caught by Other Workers

Researchers at Arizona State University have found that worker ants attempting to mate while a queen is present signal themselves chemically, and are prevented from doing so by other worker ants.

Typically, the queen is the sole reproductive female in an ant colony, with the population filled with various male and female workers. Scientists found that when female ants (Aphaenogaster cockerelli) other than the queen are fertile, they emit a chemical hydrocarbon to attract a mate. This hydrocarbon is detected by nestmates, who will proceed to physically restrain the female from mating in favor of the queen. These hydrocarbon signals are also used to discriminate between eggs laid by the queen and those of other worker ants.

Experiments using a similar synthetic chemical compound applied to workers attracted aggression from others in colonies with a queen but it failed to have a similar effect in colonies without a queen, where female workers lay eggs until a new queen is obtained.

These results appear in the January 8th online edition of Current Biology.

Photo: ScienceDaily

Monday, January 12, 2009

Mosquitoes Harmonize Before Mating

Scientists at Cornell University have discovered that male and female mosquitoes will synchronize their wing-beat frequencies and produce harmonic calls before mating.

Male mosquitoes (Aedes aegypti) typically beat their wings at 400 Hz (beats per second) and females at 600 Hz. But when the two come within audible distance of a few centimeters, both male and female wing beats approach 1200 Hz, a harmonic of each individual's normal rate. This rate is greater than what was believed to be the mosquitoes' upper hearing limit.

In addition to wing beats, each mosquito also adjusts the resonance of their thoracic box to produce harmonic mating calls. The female will settle at her third harmonic (three times her fundamental frequency) and the male will settle at his second harmonic (two times his fundamental frequency). This also demonstrates that the female mosquito is not deaf, as was previously believed.

Knowing the details of mosquito mating and reproduction helps researchers develop effective pest control strategies. If the reproductive cycle can be interrupted, the mosquito population in places at risk of diseases such as dengue or yellow fever can be controlled.

This study is available online on January 8th and in a February edition of Science.

Photo: ScienceDaily

Sunday, January 11, 2009

Unexplained "Roar" From Distant Space Detected

Astronomers from NASA's Goddard Space Flight Center have discovered a loud "roar" of radio signals of unknown origin and more than six times louder than expected.

Scientists intended to study the faint residual heat from star formation using a balloon-borne instrument named ARCADE (Absolute Radiometer for Cosmology, Astrophysics and Diffuse Emission). At an altitude of 120,000 feet, the device instead detected a booming background noise of radio signals from deep space six times louder than anticipated. An analysis has discounted any known origins of the noise, such as stellar activity, radiogalaxies or other accountable sources of radiation.

Not only is this signal louder than expected, it is also louder than could be produced through the combined emissions of all known radio phenomena in the universe. As well as being a new discovery, this background noise could make astronomical measurements more difficult, as fainter signals may be obscured by this new phenomenon.

At this time, the source and location of this noise remains undetermined and unexplained.

These results were presented on January 5th at the 213th annual meeting of the American Astronomical Society.

Source: SPACE.com

Saturday, January 10, 2009

Pterosaurs Used Four Legs, Different from Modern Birds

A scientist at the Center for Functional Anatomy and Evolution at the Johns Hopkins University School of Medicine has shown that pterosaurs possessed a fundamentally different body structure from either modern birds or other dinosaurs.

Believed to be descendants of dinosaurs, modern birds have strong wings instead of forelegs and a pair of strong hind legs. These hind legs are used for launching into flight but become useless payload once in the air; thus, a maximum weight function exists for flying birds. However, pterosaurs ("winged lizards") achieved flight even when their bodies were as large as modern giraffes and weighed as much as 500 pounds.

By analyzing their comparative bone structure from fossil records along with modern mathematical models of flight, no solutions could be found that provided flight using just two hind legs to launch. Therefore, pterosaurs must have used all four legs to launch into winged flight with a series of long-jumps. These four limbs were equally adapted to movement on the ground, as the winged surface folded back with pterosaurs essentially walking on their knuckles.

This study appeared in a recent issue of Zitteliana (no website).

Photo: ScienceDaily

Friday, January 9, 2009

Spookfish Uses Mirrored Eyes to See

Scientists at Tuebingen University have discovered that the deep-sea spookfish is the first vertebrate to develop natural mirrors to focus light into its eyes.

Known for about 120 years, this first live specimen of the brownsnout spookfish (Dolichopteryx longipes) was caught last year off the coast of Tonga. Spookfish generally live at ocean depths of 1000 meters or more and in near total darkness. Their two compound eyes consist of two parts each, one of which is a mirrored surface used to focus faint traces of light into an image on the other part.

These mirrors are made up of guanine crystals, a naturally occurring substance in fish scales that produces a pearly, iridescent effect and has a high reflectivity. The mirrored portions are curved in such a way as to focus the reflected light on the fish's retina.

These results appear in a recent issue of Current Biology.

Photo: BBC News

Thursday, January 8, 2009

Pink Iguanas Offer Insight into Evolution

A study led by the University of Roma Tor Vergata has identified a new species of pink iguanas native to the Galapagos Islands that provides new insight into Darwin's theory of natural selection.

These pink iguanas with black stripes were first seen in 1986 and rarely thereafter. Researchers have linked them through genetic analysis with other iguana species native to the islands, and estimate the species diverged about five million years ago. The new species provides evidence for the earliest evolutionary split among the archipelago's rich spectrum of life.

Charles Darwin developed his theory of natural selection and species specialization during a visit to the Galapagos in 1835. He studied the beaks of the native finches and how the various species each adapted in shape and structure to the environments and local food of individual islands. Darwin never observed this new iguana species.

Less than 40 pink iguanas have been documented to date, all living around a 350,000-year-old volcano.

This study appeared in a recent edition of the Proceedings of the National Academy of Sciences.

Photo: Yahoo! News

Wednesday, January 7, 2009

Milky Way Larger, More Massive than Previously Believed

New measurements of our Milky Way galaxy by the Harvard-Smithsonian Center for Astrophysics have shown it to be larger and more massive than previous data revealed, and spinning at a much faster rate.

Astronomers used the National Science Foundation’s Very Long Baseline Array (VLBA) radio telescope to produce a more detailed, three-dimensional model of the Milky Way. They found the spiral arms of the Milky Way to be moving at about 568,000 miles per hour, roughly 15% faster than previous, less accurate measurements. From these data, the mass of the galaxy has been estimated at least 50% greater than previously believed. The new model also reveals the Milky Way's breadth to be about 15% larger than before.

The Milky Way galaxy has long been believed to be significantly smaller than the nearby Andromeda galaxy, the two dominant members of the cluster of galaxies known as the Local Group. The new data shows the Milky Way to be of a size and mass equivalent to that of Andromeda.

These results were presented on January 5th at the 213th annual meeting of the American Astronomical Society.

Photo: Yahoo! News

Tuesday, January 6, 2009

Star Formation Discovered Near Galaxy Center

Astrophysicists at the Harvard-Smithsonian Center for Astrophysics and the Max Planck Institute for Radio Astronomy have discovered two stars in the process of formation near the Milky Way galaxy's center.

Stars form as massive clouds of dust and gas coalesce under their own gravitational attraction. But at this location, just a few light years from the galaxy's center, the gravitational forces were believed to be too strong to allow the formation of stars. Scientists believed the gravitational tides present would tear apart any gas clouds acting as solar nurseries.

A supermassive (4 million solar masses) black hole is believed to sit at the Milky Way's center, with its gravity dominating the local area. These two proto-stars were discovered in the act of formation 7 and 10 light years from the galactic center. Their formation could mean the gas at the center is much denser than previously thought, dense enough to overcome the prevailing gravitational forces.

These results were presented on January 5th at the 213th annual meeting of the American Astronomical Society.

Photo: SPACE.com

Monday, January 5, 2009

Cancer Cells Resist Cell Death

Researchers at the Chinese University of Hong Kong have found that cancer cells can overcome the programmed cell death included with normal cells.

In a process known as apoptosis, normal human cells contain a genetically encoded signal to end their individual lives after a certain point. This process helps keep the body healthy by preventing damaged or defective cells from continuing to multiply. However, cancer cells lack this encoding and continue to multiply without limit, developing into a tumor.

The researchers exposed human cervical, skin, liver and breast cancer cells to a variety of chemicals, each of which triggers apoptosis in normal human cells. Not only did the cancer cells survive, once the chemicals were removed they recovered and again started to multiply.

This research may show why some cancers are resistant to certain chemotherapies, and will assist in the development of more effective treatments.

These results were published in a recent issue of the British Journal of Cancer.

Photo: BBC News

Friday, January 2, 2009

Nanodiamonds Point to Prehistoric Impact Event

A 26-member multi-institutional team led by the University of Oregon has discovered a nanodiamond-rich soil layer at six different sites across the North American continent.

Nanodiamonds (nanometer-sized gems) are produced under high-temperature, high-pressure conditions, which occur rarely in nature. The presence of this nanodiamond formation supports the theory of a scattered comet impact about 12,900 years ago.

The nanodiamonds were found only in what is called the Younger Dryas Boundary, a geologic strata dated at about 12,900 years ago. Below this boundary layer are a wealth of prehistoric fossils from now-extinct species, including artifacts from the prehistoric Clovis culture. This strata also marks the beginning of a 1300-year cold period known as the Younger Dryas. A series of clustered comet impacts may have been responsible for this extinction event.

The sites are identified as Murray Springs, Arizona; Bull Creek, Oklahoma; Gainey, Michigan; Topper, South Carolina; Lake Hind, Manitoba; and Chobot, Alberta.

These results are reported in the January 2nd issue of Science.

Photo: ScienceDaily

Thursday, January 1, 2009

Large Dinosaur Site Found in China

Researchers from the Chinese Academy of Sciences have located what they believe to be the largest single site for dinosaur fossils in the world.

The city of Zhucheng in Shandong Province, known locally as "Dinosaur City," is the site of a large fossil field under research since the 1960s. Since March 2008, more than 7600 fossil bones have been excavated from this site alone, with many more found in nearby locations.

These fossils date from the late Cretaceous period, around the time when paleontologists believe dinosaurs became extinct. The bones include many specimens from ankylosaurus to tyrannosaurus, including what may be the largest hadrosaur ("duck-billed" dinosaur) ever found.

Full results are yet to be published.

Photo: BBC News

Welcome to Galileo's Lens

Science does not live in a school textbook. Science is an ongoing pursuit, with new and fascinating discoveries being made around the world on a daily basis. Too often, these otherwise interesting news items are lost in a sea of political and entertainment reporting, or simply a media ill-equipped or uninterested in covering these topics.

The purpose of this blog is to feature modern news stories dealing with the full range of scientific topics, from archaeology to zoology, along with limited explanatory text from a professional science writer. This is not an original news source but merely a media conduit and outlet for commentary, and full credit belongs to the originating sources of this material.

I am a full-time science and education writer and technical editor, and I welcome any and all feedback. If there is a science story that I have missed or if you have questions about a topic shown here, feel free to send me an e-mail.