Monthly Archives: December 2014

For several decades scientists have been interested in the ability of psychrophilic (cold- loving) microbial communities to degrade the various components of crude oil, which is a process known as bioremediation. Because temperature has a direct impact on enzyme activity there is a concern that, at very low temperatures, the microbial community might be inhibited in its ability to undertake bioremediation. The benefits of bioremediation were seen in the response of the microbial community during the infamous Deepwater Horizon event in the Gulf of Mexico. Indigenous bacteria deep in the water column consumed much of the escaping oil before it had the opportunity to reach the surface, lowering (but not eliminating) the ecological impact of that disaster. Despite the subtropical location of the Deepwater Horizon, the water temperature where much of this bioremediation took place is only 5 degrees Celsius. This is not much warmer than summertime Arctic surface waters…

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Using an experiment carried into space on a NASA suborbital rocket, astronomers at Caltech and their colleagues have detected a diffuse cosmic glow that appears to represent more light than that produced by known galaxies in the universe. The researchers, including Caltech Professor of Physics Jamie Bock and Caltech Senior Postdoctoral Fellow Michael Zemcov, say that the best explanation is that the cosmic light — described in a paper published November 7 in the journal Science — originates from stars that were stripped away from their parent galaxies and flung out into space as those galaxies collided and merged with other galaxies. The discovery suggests that many such previously undetected stars permeate what had been thought to be dark spaces between galaxies, forming an interconnected sea of stars. “Measuring such large fluctuations surprised us, but we carried out many tests to show the results are reliable,” says Zemcov, who led…

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Human-caused climate change, ocean acidification and species extinctions may eventually threaten the collapse of civilization, according to some scientists, while other people argue that for political or economic reasons we should allow industrial development to continue without restrictions. In a new paper, two astrophysicists argue that these questions may soon be resolvable scientifically, thanks to new data about the Earth and about other planets in our galaxy, and by combining the earth-based science of sustainability with the space-oriented field of astrobiology. “We have no idea how long a technological civilization like our own can last,” says University of Rochester astrophysicist Adam Frank. “Is it 200 years, 500 years or 50,000 years? Answering this question is at the root of all our concerns about the sustainability of human society.” “Are we the first and only technologically-intensive civilization in the entire history of the universe?” asks Frank. “If not, shouldn’t we stand…

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Climate change alters cast of winter birds MADISON — Over the past two decades, the resident communities of birds that attend eastern North America’s backyard bird feeders in winter have quietly been remade, most likely as a result of a warming climate. Writing this week in the journal Global Change Biology, University of Wisconsin-Madison wildlife biologists Benjamin Zuckerberg and Karine Princé document that once rare wintering bird species are now commonplace in the American Northeast. Using more than two decades of data on 38 species of birds gathered by thousands of “citizen scientists” through the Cornell University Laboratory of Ornithology’s Project FeederWatch, the Wisconsin researchers show that birds typically found in more southerly regions are gradually pushing north, restructuring the communities of birds that spend their winters in northern latitudes. To the causal observer of backyard birds, the list of species becoming more common includes the readily familiar: cardinals, chipping…

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You might expect that a term like “monsoon” has an agreed definition and that scientists can explain when it starts and ends. Defining the monsoon is actually quite contentious, leading to the publication of many different definitions. Some define the monsoon onset according to rainfall, wind change, cloud top temperatures, or a combination of these and other factors. Most of these different methods give results that are similar over Bangladesh. They explain that the monsoon starts in the south east part of the country and sweeps northwestward over a couple of weeks around the beginning of June. However, a couple of publications say something quite different. These publications reveal that the monsoon starts considerably –over 1 month- earlier in northeast Bangladesh. These varying results present us with a challenge. If we want to inform the people of Bangladesh about the monsoon onset, how can we decide which definition to use…

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Small red stars, known by astronomers as “M-dwarfs”, are the most abundant type of star in the sky and are also the most long-lived of all stars. This means there are plenty nearby of M-dwarfs to search for possible habitable planets, and many current and planned exoplanet surveys emphasize the search for potential worlds orbiting within the habitable zone of these low-mass stars. Astrobiologists often use the term “habitability” to indicate a planet’s ability to sustain liquid water on its surface, thereby providing conditions where life might be able to develop and thrive. The corresponding “habitable zone” describes the range of orbital distances that can support these clement conditions and not lose the water to a rapid runaway greenhouse (from too close an orbit) or a cool condensing atmosphere (from too far an orbit). The problem with planets orbiting M-dwarfs is that they are prone to fall into “synchronous rotation”…

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Cutting-edge paper by Professor George Fraser — who tragically died in March this year — and colleagues at the University of Leicester provides first potential indication of direct detection of Dark Matter — something that has been a mystery in physics for over 30 years. Space scientists at the University of Leicester have detected a curious signal in the X-ray sky — one that provides a tantalising insight into the nature of mysterious Dark Matter. The Leicester team has found what appears to be a signature of ‘axions’, predicted ‘Dark Matter’ particle candidates — something that has been a puzzle to science for years. In a study being published on Monday 20 October in the Monthly Notices of the Royal Astronomical Society, the University of Leicester scientists describe their finding of a signal which has no conventional explanation. As first author Professor George Fraser, who sadly died in March of…

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