Tuesday, February 16, 2010

ASTRONOMERS DISCOVER COOL STARS IN NEARBY SPACE

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An international team, led by astronomers at the University of Hertfordshire have discovered what may be the coolest sub-stellar body ever found outside our own solar system.

Using the United Kingdom Infrared Telescope (UKIRT) in Hawaii, a discovery has been made of an object which is technically known as a brown dwarf.

What has excited astronomers are its very peculiar colours, which actually make it appear either very blue or very red, depending on which part of the spectrum is used to look at it.

The object is known as SDSS1416+13B and it is in a wide orbit around a somewhat brighter and warmer brown dwarf, SDSS1416+13A. The brighter member of the pair was detected in visible light by the Sloan Digital Sky Survey. By contrast, SDSS1416+13B is only seen in infrared light. The pair is located between 15 and 50 light years from the solar system, which is quite close in astronomical terms.

"This looks like being the fourth time in three years that the UKIRT has discovered made a record breaking discovery of the coolest known brown dwarf, with an estimated temperature not far above 200 degrees Celsius,” said Dr Philip Lucas at the University of Hertfordshire’s School of Physics, Astronomy and Mathematics.

“We have to be a bit careful about this one because its colours are so different than anything seen before that we don't really understand it yet. Even if it turns out that the low temperature is not quite record breaking, the colours are so extreme that this object will keep a lot of physicists busy trying to explain it.”

SDSS1416+13B was first noticed by Dr Ben Burningham of the University of Hertfordshire as part of a dedicated search for cool brown dwarfs in the UKIRT Infrared Deep Sky Survey (UKIDSS). The object appeared far bluer at near infrared wavelengths than any brown dwarf seen before. A near infrared spectrum taken with the Japanese Subaru Telescope in Hawaii showed that it is a type of brown dwarf called a T dwarf, which has a lot of methane in its atmosphere, but with peculiar features including a big gap at certain wavelengths.

Dr Burningham soon noticed that a previously observed brighter star (SDSS1416+13A) which appears close by in the UKIDSS discovery image was also a brown dwarf. Team member Dr Sandy Leggett, of the Gemini Observatory, then used the orbiting Spitzer Space Telescope to investigate SDSS1416+13B at longer wavelengths. She measured its colour at mid-infrared wavelengths, which are thought to be the most reliable indicator of temperature, and found that it is the reddest known brown dwarf at these wavelengths by some margin. Comparison with theoretical models of the brown dwarf atmospheres then provided a temperature estimate of about 500 Kelvin (227 degrees Celsius).

"The fact that it is a binary companion to a warmer brown dwarf that also has an unusual spectrum is helping us to fill in some gaps in our understanding", says Dr Burningham. "It seems likely that both brown dwarfs are somewhat poor in heavy elements. This can be explained if they are very old, which also fits with the very low temperature of the faint companion."

Too small to be stars, brown dwarfs have masses smaller than stars but larger than gas giant planets like Jupiter. Due to their low temperature these objects are very faint in visible light, and are detected by their glow at infrared wavelengths. They were originally dubbed "brown dwarfs" long before any were actually discovered, to describe the idea of bodies that were cooler, fainter and redder than red dwarf stars, with the colour brown representing the mix of red and black.

(Photo: U. Hertfordshire)

University of Hertfordshire

: 3-D SCAFFOLD PROVIDES CLEAN, BIODEGRADABLE STRUCTURE FOR STEM CELL GROWTH

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Medical researchers were shocked to discover that virtually all human embryonic stem cell lines being used in 2005 were contaminated. Animal byproducts used to line Petri dishes had left traces on the human cells. If those cells had been implanted in a human body they likely would have been rejected by the patient's immune system.

Even today, with new stem cell lines approved for use in medical research, there remains a risk that these cells will be contaminated in the same way. Most research labs still use animal-based "feeder layers" because it remains the cheapest and most reliable way to get stem cells to multiply.

Materials scientists at the University of Washington have now created an alternative. They built a three-dimensional scaffold out of a natural material that mimics the binding sites for stem cells, allowing the cells to reproduce on a clean, biodegradable structure. Results published in the journal Biomaterials show that human embryonic stem cells grow and multiply readily on the structure.

"The major challenge for stem cell therapy today is it's very difficult to make a lot of them with high purity," said lead author Miqin Zhang, a UW professor of materials science and engineering. "So far it seems like this material is very good for stem cell renewal."

Medical researchers hope to someday use stem cells to grow new tissues and organs. Key to the research is the fact that new cells maintain the property that holds medical promise -- the ability to differentiate into any of the more than 220 cell types in the adult human body.

Growing the cells in three dimensions better resembles conditions in the human body. It also allows mass production, which will be needed for any clinical applications.

"Three-dimensional scaffolds are an active area of research," said Carol Ware, a UW professor of comparative medicine and expert on stem cells. "They are not commonly used yet, but will be important to transition embryonic stem cells to the clinic. To date, nobody has found a perfect matrix."

Zhang's cylindrical scaffold is made of chitosan, found in the shells of crustaceans, and alginate, a gelatinous substance found in algae. Chitosan and alginate have a structure similar to the matrix that surrounds cells in the body, to which cells can attach. Different processing techniques can make the scaffold out of interconnected pores of almost any size, Zhang said.

Researchers first seeded the scaffold with 500,000 embryonic stem cells, and after 21 days the scaffold was completely saturated. The cells infiltrated the structure, Zhang added, unlike other materials where cells often grow only on the surface.

"This scaffold mimics the extracellular matrix at the atomic level, and so the cells are able to grow in this environment," Zhang said.

To retrieve the cells, researchers immersed the scaffold in a mild solution. The structure is biodegradable and so dissolved to release the stem cells. One also could implant the stem cell-covered scaffold directly into the body.

Analysis of gene activity and testing in the lab and in mice showed that the new stem cells retained the same properties as their predecessors.

Other researcher groups are also looking for alternatives to feeder layers. The leading contenders are scaffolds coated with custom proteins designed to mimic the key properties of the animal cells in the feeder layer. Such products are expensive and difficult to produce in a consistent manner, Zhang said. The proteins also get used up in a few days and have to be replaced, making them costly and time-consuming for everyday use.

"Our scaffold is made of natural materials that are already FDA-approved for food and biomedical applications. Also, these materials are unlimited, and the cost is cheap," she said.

Zhang's group is now working to build a scaffold larger than the current dime-sized prototype, and is collaborating with the UW's Institute for Stem Cells and Regenerative Medicine and UW School of Medicine to try growing different types of stem cells, including those from umbilical cord blood and bone marrow, in the material. They will try to get the resulting cells to differentiate into bone, neuron, muscle and liver cells.

(Photo: University of Washington)

University of Washington

WHITE ROOFS MAY SUCCESSFULLY COOL CITIES

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Painting the roofs of buildings white has the potential to significantly cool off cities and mitigate some impacts of global warming, results of a new study indicate.

The research, the first computer modeling study to simulate the impacts of white roofs on urban areas worldwide, suggests there may be merit to the idea of turning roofs white.

But the study team, led by scientists at the National Center for Atmospheric Research (NCAR) in Boulder, Colo., cautions that there are still many hurdles between the concept and actual use of white roofs to counteract rising temperatures.

"Our research demonstrates that white roofs, at least in theory, can be an effective method for reducing urban heat," says NCAR scientist Keith Oleson, the lead scientist on the study. "It remains to be seen if it's actually feasible for cities to paint their roofs white, but the idea certainly warrants further investigation."

Results of the research are slated for publication later this winter in the American Geophysical Union (AGU) journal Geophysical Research Letters.

The work was funded by the National Science Foundation (NSF), NCAR's sponsor. "Climate change mitigation research is an extremely important topic," says Steve Nelson, NSF program director for NCAR. "Whether on white roofs or other climate change mitigation subjects, it's important to consider the many feedbacks and complicating considerations that make research in this area very complex."

Cities are particularly vulnerable to climate change because they are warmer than outlying rural areas.

Asphalt roads, tar roofs and other artificial surfaces absorb heat from the sun, creating an urban "heat island effect" that can raise temperatures on average by 2-5 degrees Fahrenheit (about 1-3 degrees Celsius) or more, compared to rural areas.

White roofs would reflect some of that heat back into space and cool temperatures, much as wearing a white shirt on a sunny day can be cooler than wearing a dark shirt.

The study team used a newly developed computer model to simulate the amount of solar radiation that is absorbed or reflected by urban surfaces.

The model simulations, which provide scientists with an idealized view of different types of cities around the world, indicate that, if every roof were entirely painted white, the urban heat island effect could be reduced by 33 percent.

This would cool the world's cities by an average of about 0.7 F, with the cooling influence being particularly pronounced during the day, especially in summer.

The authors emphasize that their research should be viewed as a hypothetical look at typical city landscapes rather than the actual rooftops of any one city.

In the real world, the cooling impact might be somewhat less because dust and weathering would cause the white paint to darken over time and parts of roofs would remain unpainted because of openings such as heating and cooling vents.

In addition, white roofs would have the effect of cooling temperatures within buildings. As a result, depending on the local climate, the amount of energy used for space heating and air conditioning could change, which could affect both outside air temperatures and the consumption of fossil fuels such as oil and coal that are associated with global warming.

Depending on whether air conditioning or heating is affected more, this could either magnify or partially offset the impact of the roofs.

"It's not as simple as just painting roofs white and cooling off a city," Oleson says.

The research indicated that some cities would benefit more than others from white roofs, depending on such factors as the city's location and design. Among the factors to be considered are:

•Roof density. Cities where roofs are packed closely together would cool more.
•Construction. Roofs that allow large amounts of heat from the sun to penetrate the interior of a building (as can happen with metal roofs and little insulation) are less effective in cooling outside temperatures when painted white.
•Location. White roofs tend to have a larger impact in relatively warm climates that receive strong, year-round sunlight.

While the model did not have enough detail to capture individual cities, it did show the change in temperatures in larger metropolitan regions. The New York area, for example, would cool in summer afternoons by almost 2 degrees Fahrenheit.

The study team used a new computer model, developed by Oleson and colleagues, that is designed to assess the impacts of a changing climate on urban populations and explore options for countering rising temperatures.

This urban canyon model simulates temperature changes in city landscapes, capturing such factors as the influence of roofs, walls, streets, and green spaces on local temperatures.

Oleson has successfully linked the urban canyon model to a computer simulation of worldwide climate, the NCAR-based Community Climate System Model, thereby enabling researchers to study the interactions between global climate change and urban areas.

The new model does not yet have the power to replicate the architecture and design of specific cities. Instead, the research team created abstractions of cities in the model, using classes of population density, urban design and building construction.

Oleson and his colleagues plan to continue refining the model to provide more information for policymakers concerned about protecting urban populations from the risks associated with heat waves and other changes in climate.

"It's critical to understand how climate change will affect vulnerable urban areas, which are home to most of the world's population," says NCAR scientist Gordon Bonan, a co-author of the paper.

(Photo: Maria Jose-Vinas, American Geophysical Union)

National Science Foundation (NSF)

DINOSAUR DISCOVERY HELPS SOLVE PIECE OF EVOLUTIONARY PUZZLE

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Through an expedition to the Gobi Desert of China, scientists have solved the puzzle of how one group of dinosaurs came to look like birds--independent of birds.

The discovery extends the fossil record of the family Alvarezsauridae--a bizarre group of bird-like dinosaurs with a large claw on the hand and very short, powerful arms--back 63 million years, further distancing the group from birds on the evolutionary tree.

Until now, there was no direct evidence that dinosaurs of this type lived during the Late Jurassic, some 160 million years ago.

"This National Science Foundation (NSF)-supported research sheds light on the poorly understood early evolution of birds in the Late Jurassic in China by eliminating alvarezsaurids as ancestors of the birds," says H. Richard Lane, program director in NSF's Division of Earth Sciences.

George Washington University (GWU) scientist Jonah Choiniere named the newly discovered species of dinosaur, called Haplocheirus sollers (meaning simple, skillful hand). Choiniere's research results are reported in this week's issue of the journal Science.

"Haplocheirus is a transitional fossil, because it shows an early evolutionary step in how the bizarre hands of later alvarezsaurs evolved from earlier predatory dinosaurs," said Choiniere. "The fossil also confirms our predictions that Alvarezsauridae should have been evolving in the Late Jurassic time period."

The fossil of the new species contains several distinguishing features that link it to Alvarezsauridae, the family of dinosaurs that includes species such as Mononykus (meaning one claw) and that was previously thought to be a flightless offshoot of ancient birds due to skeletal similarities.

Despite the similarity between the skeletons, Choiniere's research demonstrates that the family Alvarezsauridae evolved in parallel to birds and did not descend from them.

The new species shows some of the earliest evolutionary stages in the development of a short, powerful arm with a single functional claw that may have been used for digging termites.

The Late Jurassic is an important time period for bird evolution, as evidence suggests that birds first evolved from theropod dinosaurs at that time.

Paradoxically, fossils of dinosaurs closely related to birds from this time period are extremely rare.

The ten-foot long, nearly complete skeleton of Haplocheirus sollers specimen was found preserved in river-rock in the Xinjiang Autonomous Region of northwestern China, a region well-known for its Late Jurassic fossils.

It was collected during a series of expeditions to Xinjiang co-led by James Clark of GWU and Xu Xing of the Chinese Academy of Sciences, co-authors of the paper.

These expeditions were extremely successful, resulting in the discovery of a small, agile relative of crocodilians (Junggarsuchus sloani); the oldest horned dinosaur (Yinlong downsi); one of the oldest tyrannosaurs (Guanlong wucaii); and several skeletons of an unusual, toothless new ceratosaurian dinosaur (Limusaurus inextricabilis) that were buried while stuck in mud pits.

"The primary goal of our expeditions was to find evidence of the theropod dinosaurs closest to birds, and the discovery of Haplocheirus is one of our major discoveries," said Clark. "This spectacular skeleton shows how the strange arms of Mononykus and other alvarezsaurs evolved from a more typically theropod grasping hand."

Theropod dinosaurs include charismatic meat-eaters like Tyrannosaurus rex but also modern birds. Alvarezsaurs are one of several groups of theropods closely related to birds, including well-known species like Velociraptor.

(Photo: Zina Deretsky, National Science Foundation)

National Science Foundation

BLACK CARBON A SIGNIFICANT FACTOR IN MELTING OF HIMALAYAN GLACIERS

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The fact that glaciers in the Himalayan mountains are thinning is not disputed. However, few researchers have attempted to rigorously examine and quantify the causes. Lawrence Berkeley National Laboratory scientist Surabi Menon set out to isolate the impacts of the most commonly blamed culprit—greenhouse gases, such as carbon dioxide—from other particles in the air that may be causing the melting. Menon and her collaborators found that airborne black carbon aerosols, or soot, from India is a major contributor to the decline in snow and ice cover on the glaciers.

“Our simulations showed greenhouse gases alone are not nearly enough to be responsible for the snow melt,” says Menon, a physicist and staff scientist in Berkeley Lab’s Environmental Energy Technologies Division. “Most of the change in snow and ice cover—about 90 percent—is from aerosols. Black carbon alone contributes at least 30 percent of this sum.”

Menon and her collaborators used two sets of aerosol inventories by Indian researchers to run their simulations; their results were published online in the journal Atmospheric Chemistry and Physics.

The actual contribution of black carbon, emitted largely as a result of burning fossil fuels and biomass, may be even higher than 30 percent because the inventories report less black carbon than what has been measured by observations at several stations in India. (However, these observations are too incomplete to be used in climate models.) “We may be underestimating the amount of black carbon by as much as a factor of four,” she says.

The findings are significant because they point to a simple way to make a swift impact on the snow melt. “Carbon dioxide stays in the atmosphere for 100 years, but black carbon doesn’t stay in the atmosphere for more than a few weeks, so the effects of controlling black carbon are much faster,” Menon says. “If you control black carbon now, you’re going to see an immediate effect.”

The Himalayan glaciers are often referred to as the third polar ice cap because of the large amount of ice mass they hold. The glacial melt feeds rivers in China and throughout the Indian subcontinent and provide fresh water to more than one billion people.

Atmospheric aerosols are tiny particles containing nitrates, sulfates, carbon and other matter, and can influence the climate. Unlike other aerosols, black carbon absorbs sunlight, similar to greenhouse gases. But unlike greenhouse gases, black carbon does not heat up the surface; it warms only the atmosphere.

This warming is one of two ways in which black carbon melts snow and ice. The second effect results from the deposition of the black carbon on a white surface, which produces an albedo effect that accelerates melting. Put another way, dirty snow absorbs far more sunlight—and gets warmer faster—than pure white snow.

Previous studies have shown that black carbon can have a powerful effect on local atmospheric temperature. “Black carbon can be very strong,” Menon says. “A small amount of black carbon tends to be more potent than the same mass of sulfate or other aerosols.”

Black carbon, which is caused by incomplete combustion, is especially prevalent in India and China; satellite images clearly show that its levels there have climbed dramatically in the last few decades. The main reason for the increase is the accelerated economic activity in India and China over the last 20 years; top sources of black carbon include shipping, vehicle emissions, coal burning and inefficient stoves. According to Menon’s data, black carbon emitted in India increased by 46 percent from 1990 to 2000 and by another 51 percent from 2000 to 2010.

However, black carbon’s effect on snow is not linear. Menon’s simulations show that snow and ice cover over the Himalayas declined an average of about one percent from 1990 to 2000 due to aerosols that originated from India. Her study did not include particles that may have originated from China, also known to be a large source of black carbon. (See “Black soot and the survival of the Tibetan glaciers,” by James Hansen, et al., published last year in the Proceedings of the National Academy of Sciences.) Also the figure is an average for the entire region, which saw increases and decreases in snow cover. As seen in the figure, while a large swath of the Himalayas saw snow cover decrease by at least 16 percent over this period, as reported by the National Snow and Ice Data Center, a few smaller patches saw increases.

Menon’s study also found that black carbon affects precipitation and is a major factor in triggering extreme weather in eastern India and Bangladesh, where cyclones, hurricanes and flooding are common. It also contributes to the decrease in rainfall over central India. Because black carbon heats the atmosphere, it changes the local heating profile, which increases convection, one of the primary causes of precipitation. While this results in more intense rainfall in some regions, it leads to less in other regions. The pattern is very similar to a study Menon led in 2002, which found that black carbon led to droughts in northern China and extreme floods in southern China.

“The black carbon from India is contributing to the melting of the glaciers, it’s contributing to extreme precipitation, and if black carbon can be controlled more easily than greenhouse gases like CO2, then it makes sense for India to regulate black carbon emissions,” says Menon.

(Photo: LBNL)

Lawrence Berkeley National Laboratory

NEW TECHNIQUE FOR DETECTING EARTH-LIKE PLANETS

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Astronomers have discovered a new ground-based technique to study the atmospheres of planets outside our Solar System, accelerating our search for Earth-like planets with life-related molecules. Their work is reported in the journal Nature.

The scientists developed the new technique by using NASA’s relatively small Earth-based Infrared telescope to identify an organic molecule in the atmosphere of a Jupiter-sized planet nearly 63 light-years away. Using a novel calibration method to remove systematic observation errors, they obtained a measurement revealing details of the exoplanet’s atmospheric composition and conditions, an unprecedented achievement from an Earth-based observatory.

Dr Giovanna Tinetti from University College London (UCL), whose work on the project was funded by the Science and Technology Facilities Council (STFC), said, “The final goal is to observe the atmosphere of a planet with the capability to support life. We’re not there yet, but the possibility to use ground-based telescopes in combination with space-based observatories, will speed up the work of studying exoplanet atmospheres.”

Lead author Mark Swain, an astronomer at NASA’s Jet Propulsion Laboratory, added, “The fact that we have used a relatively small, ground-based telescope is exciting because it implies that the largest telescopes on the ground, using this technique, may be able to characterize terrestrial exoplanet targets.”

Currently, more than 400 exoplanets are known. Most are gaseous like Jupiter, but some "super-Earths" are thought to be large terrestrial, or rocky, worlds. A true Earth-like planet the same size as our planet and distance from its star has yet to be discovered. NASA's Kepler mission is searching from space now, and is expected to find several of these earthly worlds.

On Aug. 11, 2007, Swain and his team turned the infrared telescope to the hot, Jupiter-size planet HD 189733b in the constellation Vulpecula. Every 2.2 days, the planet orbits a K-type main sequence star slightly cooler and smaller than our Sun. HD189733b had already yielded breakthrough advances in exoplanet science, including detections of water vapour, methane and carbon dioxide using space telescopes. Using the new technique, the astronomers successfully detected carbon dioxide and methane in the atmosphere of HD 189733b with a spectrograph, which splits light into its components to reveal the distinctive spectral signatures of different chemicals. Their key work was development of the novel calibration method to remove systematic observation errors caused by the variability of Earth’s atmosphere and instability due to the movement of the telescope system as it tracks its target.

“As a consequence of this work, we now have the exciting prospect that other suitably equipped yet relatively small ground-based telescopes should be capable of characterizing exoplanets,” said John Rayner, the NASA Infrared Telescope Facility support scientist who built the SpeX spectrograph used for these measurements. “On some days we can't even see the Sun with the telescope, and the fact that on other days we can now obtain a spectrum of an exoplanet 63 light-years away is astonishing.”

In the course of their observations, the team found unexpected bright infrared emission from methane that stands out on the day side of HD198733b. This could indicate some kind of activity in the planet’s atmosphere which could be related to the effect of ultraviolet radiation from the planet’s parent star hitting the planet’s upper atmosphere, but more detailed study is needed.

“An immediate goal for using this technique is to more fully characterize the atmosphere of this and other exoplanets, including detection of organic and possibly prebiotic molecules” like those that preceded the evolution of life on Earth, said Swain. “We’re ready to undertake that task.” Some early targets will be the super-Earths. Used in synergy with observations from NASA’s Hubble, Spitzer and the future James Webb Space Telescope, the new technique “will give us an absolutely brilliant way to characterize super-Earths,” Swain said.

(Photo: NASA)

Science and Technology Facilities Council

YORK STUDY MAPS THE EFFECTS OF ACUPUNCTURE ON THE BRAIN

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Important new research about the effects of acupuncture on the brain may provide an understanding of the complex mechanisms of acupuncture and could lead to a wider acceptability of the treatment.

The study, by researchers at the University of York and the Hull York Medical School published in Brain Research, indicates that acupuncture has a significant effect on specific neural structures. When a patient receives acupuncture treatment, a sensation called deqi can be obtained; scientific analysis shows that this deactivates areas within the brain that are associated with the processing of pain.

Dr Hugh MacPherson, of the Complementary Medicine Research Group in the University's Department of Health Sciences, says: "These results provide objective scientific evidence that acupuncture has specific effects within the brain which hopefully will lead to a better understanding of how acupuncture works."

Neuroscientist Dr Aziz Asghar, of the York Neuroimaging Centre and the Hull York Medical School, adds: "The results are fascinating. Whether such brain deactivations constitute a mechanism which underlies or contributes to the therapeutic effect of acupuncture is an intriguing possibility which requires further research."

Last summer, following research conducted in York, acupuncture was recommended for the first time by the National Institute for Health and Clinical Excellence (NICE) as a treatment option for NHS patients with lower back pain. NICE guidelines now state that GPs should 'consider offering a course of acupuncture comprising a maximum of 10 sessions over a period of up to 12 weeks' for patients with this common condition.

Current clinical trials at the University of York are investigating the effectiveness and cost-effectiveness of acupuncture for Irritable Bowel Syndrome (IBS) and for depression. Recent studies in the US have also shown that acupuncture can be an effective treatment for migraines and osteoarthritis of the knee.

The York team believe that the new research could help to clear the way for acupuncture to be more broadly accepted as a treatment option on the NHS for a number of medical conditions.

University of York

MERGING GALAXIES CREATE A BINARY QUASAR

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Astronomers have found the first clear evidence of a binary quasar within a pair of actively merging galaxies. Quasars are the extremely bright centers of galaxies surrounding super-massive black holes, and binary quasars are pairs of quasars bound together by gravity. Binary quasars, like other quasars, are thought to be the product of galaxy mergers. Until now, however, binary quasars have not been seen in galaxies that are unambiguously in the act of merging. But images of a new binary quasar from the Carnegie Institution's Magellan telescope in Chile show two distinct galaxies with "tails" produced by tidal forces from their mutual gravitational attraction.

"This is really the first case in which you see two separate galaxies, both with quasars, that are clearly interacting," says Carnegie astronomer John Mulchaey who made observations crucial to understanding the galaxy merger.

Most, if not all, large galaxies, such as our galaxy the Milky Way, host super-massive black holes at their centers. Because galaxies regularly interact and merge, astronomers have assumed that binary super-massive black holes have been common in the Universe, especially during its early history. Black holes can only be detected as quasars when they are actively accreting matter, a process that releases vast amounts of energy. A leading theory is that galaxy mergers trigger accretion, creating quasars in both galaxies. Because most of such mergers would have happened in the distant past, binary quasars and their associated galaxies are very far away and therefore difficult for most telescopes to resolve.

The binary quasar, labeled SDSS J1254+0846, was initially detected by the Sloan Digital Sky Survey, a large scale astronomical survey of galaxies and over 120,000 quasars. Further observations by Paul Green of the Harvard-Smithsonian Center for Astrophysics and colleagues using NASA's Chandra's X-ray Observatory and telescopes at Kitt Peak National Observatory in Arizona and Palomar Observatory in California indicated that the object was likely a binary quasar in the midst of a galaxy merger. Carnegie's Mulchaey then used the 6.5 meter Baade-Magellan telescope at the Las Campanas observatory in Chile to obtain deeper images and more detailed spectroscopy of the merging galaxies.

"Just because you see two galaxies that are close to each other in the sky doesn't mean they are merging," says Mulchaey. "But from the Magellan images we can actually see tidal tails, one from each galaxy, which suggests that the galaxies are in fact interacting and are in the process of merging."

Thomas Cox, now a fellow at the Carnegie Observatories, corroborated this conclusion using computer simulations of the merging galaxies. When Cox's model galaxies merged, they showed features remarkably similar to what Mulchaey observed in the Magellan images. "The model verifies the merger origin for this binary quasar system," he says. "It also hints that this kind of galaxy interaction is a key component of the growth of black holes and production of quasars throughout our universe."

(Photo: Carnegie Institution.)

Carnegie Institution

PAY IT FORWARD: ELEVATION LEADS TO ALTRUISTIC BEHAVIOR

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Seeing someone perform a virtuous deed (especially if they are helping another person), makes us feel good, often eliciting a warm, fuzzy feeling in our chest. This positive, uplifting emotion, known as “elevation,” might make us feel great, but is it enough to get us to go out and perform good acts ourselves? According to new findings reported in Psychological Science, a journal of the Association for Psychological Science, the answer may be yes.

Psychological scientists Simone Schnall from the University of Cambridge, Jean Roper from the University of Plymouth, and Daniel M.T. Fessler from the University of California, Los Angeles, wanted to investigate the influence of elevation on behavior. Volunteers viewed either a neutral TV clip (showing scenes from a nature documentary) or an uplifting TV clip (a segment from “The Oprah Winfrey Show” showing musicians thanking their mentors) that was designed to induce feelings of elevation and then wrote an essay describing what they watched. As they received their payment and a receipt, they were to indicate if they would be willing to participate in an additional study.

The results revealed that participants who watched the uplifting TV clip were more likely to volunteer for another research study than volunteers who saw the neutral TV clip, suggesting that elevation may make us more willing to help others. However, anybody can say they will volunteer for a subsequent study or would be willing to help another person. The researchers wanted to see if elevation can result in actual helping behavior.

In the next experiment, a different set of volunteers watched one of three TV clips: the neutral TV clip or the uplifting TV clip used previously, or a clip from a British comedy, intended to induce mirth. After they viewed the TV clip, the research assistant conducting the study pretended to have problems opening up a computer file that was required for the experiment. She told the volunteers that they were free to leave but as they were leaving, she asked them if they would be willing to complete a questionnaire for another study (unbeknownst to the volunteers, the actual experiment was measuring whether or not they helped with the additional study). The researcher noted the questionnaire was boring and that the volunteers could leave whenever they wanted.

The results of this second experiment were striking — the participants who viewed the uplifting TV clip spent almost twice as long helping the research assistant than participants who saw the neutral TV clip or the comedy clip, indicating that elevation may lead to helping behavior.

The authors conclude that “by eliciting elevation, even brief exposure to other individuals’ prosocial behavior motivates altruism, thus potentially providing an avenue for increasing the general level of prosociality in society."

Psychological Science

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