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Geysers on Europa called into question

19 December 2014
New Scientist: Despite the detection by the Hubble Space Telescope last year of 200-km-high water jets erupting from the surface of Jupiter’s moon Europa, no evidence of such a geyser has been seen since. Donald Shemansky, of the University of Southern California, reported the finding at the American Geophysical Union conference in San Francisco on 18 December. Furthermore, data from NASA’s Cassini spacecraft, which flew by Jupiter in 2001, have failed to confirm the existence of the watery plumes. Either a mistake was made or the phenomenon is very rare, says Robert Pappalardo of NASA’s Jet Propulsion Laboratory in Pasadena, California.

Revamped <em>Kepler</em> spacecraft finds another exoplanet

19 December 2014
Ars Technica: Since its launch by NASA in 2009, the Kepler spacecraft has found more than 4000 planet candidates. Although crippled in 2013 by the failure of two of its four reaction wheels, Kepler has been returned to active duty by NASA scientists, who found a way to use the craft’s solar panels to point it in the right direction. Now Kepler has been able to continue its original mission of discovering Earth-like planets orbiting other stars. Although the new data are not as precise, Andrew Vanderburg of the Harvard–Smithsonian Center for Astrophysics and colleagues were able to spot yet another planet, HIP 116454b, which is 2.5 times the diameter of Earth and orbits a star that is smaller and cooler than the Sun.

NASA satellite begins to map CO<sub>2</sub> levels in Earth’s atmosphere

19 December 2014
Nature: Earlier this year NASA launched the Orbiting Carbon Observatory-2 to monitor carbon dioxide levels in Earth’s atmosphere. Although a design flaw was detected soon after launch, the problem was quickly rectified, and the satellite is now returning data on the sources and sinks of CO2. The data will allow researchers to better understand the effects of both human activities and natural systems. Through the burning of forests and fossil fuels, humans are sending some 40 billion tons of CO2 into the atmosphere, as evidenced by the high concentrations of the gas that have been detected over Africa, Australia, Brazil, China, Europe, and North America. About half remains in the atmosphere and half is absorbed by the oceans and land-based vegetation. How long the pollution will continue to be absorbed by those systems is one of the questions the satellite mission was designed to answer.

Popularizing condensed-matter physics

19 December 2014
Even when it lacks technological applications, the basic science of materials can be made appealing to nonspecialists.

Birds evacuate nesting area ahead of tornado

19 December 2014
BBC: In May 2013 Henry Streby of the University of California, Berkeley, and colleagues tagged 20 golden-winged warblers in order to monitor their seasonal 5000-km migration between Colombia and the US. The birds had just completed their journey to the Appalachian Mountains in April 2014 when their geolocators showed them taking flight once more on 26 April—one day before a series of tornadoes struck the central and southern parts of the US. Over the next five-day period, they flew a total of some 1500 km to the Gulf of Mexico and back. The researchers propose that the unexpected journey was made to avoid the severe weather, which the birds were able to anticipate because of their ability to hear the deep rumble tornadoes emit in the infrasound range. Sound in that range can travel thousands of kilometers, but it is below what humans can hear. In their paper published in Current Biology, the researchers conclude that as global warming causes ever more severe weather events, such behavioral responses of animals could be well worth studying.

<em>Washington Post</em>: “NASA’s $349 million monument to its drift”

18 December 2014
Is decline symbolized in a hugely expensive relic of the canceled Constellation lunar-return program?

Questions and answers with A. Douglas Stone

18 December 2014
In many ways, Albert Einstein undermined the seminal role he played in the development of quantum mechanics. Stone aims to set the record straight in his award-winning book.

Water discovered deep in Earth’s crust may harbor life

18 December 2014
BBC: Some of the oldest water on Earth has been discovered about 2.4 km below Earth’s surface, in a deep mine in Canada. Thought to be between 1 billion and 2.5 billion years old, the water appears to be reacting with the surrounding rock to produce hydrogen, a potential food source for living organisms. Not only was the age of the water surprising but also the fact that there is so much of it—more than all the world’s rivers, swamps, and lakes combined, according to a study published in Nature. As a result, global hydrogen production in the continental crust may be much higher than previously estimated. "It gives us a quantum change in our understanding of how much of the Earth's crust might indeed be habitable and have enough energy to sustain subsurface life,” said Barbara Sherwood Lollar of the University of Toronto in Canada, one of the authors of the study.

Mangrove forests may help protect against tsunamis

18 December 2014

New Scientist: Following the 2004 tsunami in the Indian Ocean, several studies examined satellite data to determine the ability of mangrove forests to protect communities from the destructive effects of such seismic sea waves. One study found an 8% reduction in fatalities in villages protected by mangrove forests. Another found that a 100-m-wide band of dense mangrove growth could reduce the strength of a tsunami by up to 90%. In the years since the tsunami, several groups have worked to restore and expand mangrove forests along shorelines of countries bordering the Indian Ocean. The most successful appears to be the Green Coast project run by Oxfam Novib and Wetlands International. The organizations planted mangroves in the Indonesian province of Aceh and provided loans to residents to establish new businesses in their villages. The villages were left in charge of maintaining the new mangrove trees. If 75% of the trees were still growing after 2 years, the loan debts were written off. Almost 2 million trees were planted near 70 villages, and five years after the end of the project most of the businesses are still operating.

US–Cuba accord holds promise for science

18 December 2014
Science: Yesterday President Obama and Cuban president Raúl Castro reached a landmark agreement to restore diplomatic relations between their two countries. For the past half-century, the US has imposed economic sanctions and a trade embargo on Cuba to punish the communist regime set up by Fidel Castro. The recent accord bodes well for the scientific community, according to Alan Leshner, CEO of the American Association for the Advancement of Science. The new policy could boost collaboration between scientists in the two countries, allow US groups to organize workshops and meetings in Cuba, and support the export of scientific equipment to Cuba to pursue certain areas of research, such as the study of hurricanes in the Gulf of Mexico. However, the agreement is expected to meet with opposition in the US Congress.

Airline pilot UV radiation exposure measured

18 December 2014

Telegraph: A study earlier this year revealed a higher rate of skin cancer in pilots than in the general population. A new study by Martina Sanlorenzo of the University of California, San Francisco, and her colleagues shows that every 56 minutes that airline pilots spend at a normal cruising altitude of 30 000 ft (9144 m) exposes them to as much UV radiation as a 20-minute session in an average tanning bed. They measured UV-A exposure at ground level and in cockpits during flights to Los Vegas, Nevada, in April 2014. For every 2952 ft (900 m) of altitude gained above sea level, the radiation exposure increased by 15%. At the typical cruising altitude for commercial aircraft, UV levels were more than twice those on the ground.

The heat is on for concentrated emulsions

18 December 2014
To understand the propagation of a sound wave through a scattering medium, it’s necessary to consider the conversion of energy from acoustic to thermal and back again.

Microfabrication technique doubles solar-cell efficiency

17 December 2014

MIT Technology Review: The technology behind manufacturing solar cells is similar to that behind making microprocessors. French company Soitec has exploited its expertise in microfabrication to develop a solar cell that adds four semiconductors in two layers. Each semiconductor absorbs energy from different parts of the light spectrum; together they convert sunlight to energy at a more efficient rate than one wide-spectrum semiconductor, which is more typical in other designs. Although the cell's solar efficiency is now at 46%, the process is currently expensive compared with the price of making competing products.

Satellite sees ground movement after quake

17 December 2014

BBC: Europe's Sentinel-1a satellite, which was launched earlier this year, has provided the first high-resolution images of ground movement after an earthquake. Back in August, California's Napa Valley suffered an earthquake. Because Sentinel-1a flies over and takes a snapshot of the surrounding area every 12 days, researchers have been able to track the earthquake's aftermath. The high-resolution images have captured the surface creeping forward at a rate of 5 cm per month. The data will allow researchers to see which parts of a fault line "stick" and potentially cause an earthquake and which parts flow over the surrounding rock.

US will stay in ITER

17 December 2014
Omnibus spending bill removes the threat of US withdrawal from project. The measure also boosts US domestic fusion program.

Raman spectroscopy finds rickets disease in Tudor sailors

16 December 2014
Daily Mail: Bones and artifacts from an almost 500-year-old shipwreck are now being analyzed using Raman spectroscopy and DNA analysis. When Henry VIII’s flagship Mary Rose sank in battle on 19 July 1545, more than 400 men, and one dog, died. The wreck settled into the muddy bottom on the floor of the Solent, the strait separating the Isle of Wight from mainland England. It lay there preserved until October 1982, when it was raised and an ambitious conservation effort begun. Over the next three decades, the ship’s hull underwent constant spraying with millions of liters of water and wax chemicals to preserve it. In addition, bones of the sailors who perished on board have been examined. One thing the researchers discovered was that many of the sailors appear to have suffered from metabolic bone disease, such as childhood rickets.

Modeling behavior of synthetic materials

16 December 2014

The Telegraph: Computationally modeling chemical processes from quantum mechanical principles has been a challenging task because of the large number of pieces and the large number of steps in interactions that need to be calculated. Now Peter Coveney, James Suter, and Derek Groen of University College London have developed an efficient way of modeling the behaviors of composites of clays and polymers from the quantum scale up. They were able to accurately model the characteristics of synthetic materials they'd created in the lab; they began the modeling with the behavior of the materials' electrons and then progressed to the atomic level and then to the molecular level. Their modeling system could be useful for predicting the behaviors of potential new materials, including new composites that contain molecules like graphene.

Nuclear sites get federal historical park status

16 December 2014

New York Times: On 12 December Congress approved the establishment of a new national historic park to preserve sites associated with the World War II secret Manhattan Project, which built the world's first atomic weapons. The park will encompass lands and buildings in New Mexico, Tennessee, and Washington, including the home of J. Robert Oppenheimer, the scientific director of the project, and buildings where much of the research and construction of the Trinity device and the Fat Man and Little Boy bombs took place. The effort to preserve the various sites was led by the Atomic Heritage Foundation. President Obama is expected to sign the legislation into law this week.

Densest Amazon store of carbon is in the peat

16 December 2014

BBC: A 120 000 km2 area that accounts for just 3% of the Peruvian Amazon basin contains almost 50% of the basin's carbon stock. Freddie Draper of the University of Leeds, Katy Roucoux of the University of St Andrews, and their colleagues combined two years of measurements on peat depth, density, and carbon percentage with satellite imagery to reach that conclusion. The imagery revealed that the peatlands were more widespread than expected. The direct measurements of ground carbon revealed that the peat accounted for 90% of the area's carbon. Draper and Roucoux say that the peatlands are still mostly intact but that preservation efforts should be started now to prevent any damage to the ecosystems.

Large number of methane deposits releasing gas along US East Coast

15 December 2014

Earth Magazine: Sea-floor methane deposits are commonly found leaking gas in tectonically active areas or in areas rich in petroleum. They are considered to be a potentially significant contributor of greenhouse gases. Now Adam Skarke of Mississippi State University and his colleagues have found 570 methane seeps along the tectonically quiet and oil-poor East Coast of the US. Skarke's team used multibeam sonar, commonly used for producing 3D maps of the sea floor, to find the seeps. Previous scans of the region did not have a resolution capable of detecting the small bubbles up to 1.6 km below sea level. Despite the large number of seeps found, the amount of gas being released by them is quite small. However, the discovery suggests that the search for seeps should be expanded to areas that were not previously considered likely sites.

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