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Updated: 4 days 11 hours ago

New index provides universal definition of a heat wave

30 October 2014

Nature: In response to global warming, the Heat Wave Magnitude Index (HWMI) has been devised to provide a way to compare the severity of heat waves around the world and over time. Similar to the Richter scale for comparing the magnitude of earthquakes, the HWMI is designed to be more comprehensive than previous systems by taking into account heat intensity and duration in different regions and in different years. According to the new scale, the worst heat wave to date occurred in Russia during the summer of 2010 when 55 000 people died. The HWMI also predicts that the number and size of heat waves will continue to increase throughout the 21st century, a prediction consistent with earlier research.

Suite of science projects lost when space station resupply ship exploded

30 October 2014

Science: The Tuesday evening launch of an unmanned Antares rocket from Wallops Flight Facility in Virginia ended abruptly with an explosion six seconds after liftoff. The rocket, built by Orbital Sciences Corp, was headed to the International Space Station with 748 kg of supplies and 727 kg of scientific experiments. Many of the projects lost were designed by students. One, from the Duchesne Academy of the Sacred Heart—an all-girl college preparatory school in Houston, Texas—was to investigate how well fast-growing plants, such as pea shoots, do in microgravity and when exposed to red and blue wavelengths of light. Despite the sad outcome, school administrators emphasized the importance of the experience gained in participating in the program and creating the experiments.

Icelandic eruption is releasing unusual amounts of sulfur dioxide

29 October 2014

Nature: On 29 August, the Icelandic volcano Bárðarbunga began erupting in a steady flow of lava that has not stopped. It has produced more lava than any Icelandic eruption since 1947, but the amount of sulfur dioxide it has released is far beyond any predictions. Nearly 35 000 tons of SO2 is being released daily, twice as much as produced by all European industries combined. The high levels have caused breathing problems for nearby residents and have elevated pollution readings all the way into central Europe. The Icelandic Meteorological Office is attempting to track and provide warnings about the gas cloud's movement. However, the volcano's remote location and the onset of winter are making it hard to closely monitor the eruption. The timing of the eruption was good because it began in the middle of FUTUREVOLC, an ongoing study of vulcanism and the movement of magma.

Asteroid could experience avalanches when it passes Earth

29 October 2014

Science: In 2029, a football-field-sized asteroid known as Apophis is going to pass within 35 000 km of Earth. Our planet is not in any danger, but simulations run by Derek Richardson of the University of Maryland, College Park, and his colleagues suggest that Apophis could experience avalanches, albeit very small ones. Pictures of another asteroid believed to be similar to Apophis indicate that instead being solid rock, the two asteroids are clumps of debris loosely held together by gravity. In Richardson's simulation, the tidal force of Earth's gravity caused small, slow-moving avalanches of the lighter pieces of debris on the asteroid's surface. Although astronomers will not be able to see the avalanches directly, IR pictures of the surface could reveal areas that have been uncovered as the surface shifts.

Saturn’s moon Enceladus may have snow cone at its center

29 October 2014

New Scientist: Astronomers continue to be surprised by Saturn’s moon Enceladus. Most of the planets and moons studied so far consist of a core of dense material covered by a large mantle and an outer crust. Based on computer modeling, however, Enceladus’s core can’t be stiff and rocky and also produce the huge watery plumes that have been observed shooting into space as the moon orbits Saturn. In order to generate the heat necessary to melt the icy crust and shoot the jets, the moon’s core may be more like a rubble pile with empty spaces filled with ice or water, similar to a snow cone. The finding has implications for the search for extraterrestrial life because such hydrothermal systems are important to the formation of biological organisms.

Tihiro Ohkawa

29 October 2014

Google X lab developing cancer-detecting pill

29 October 2014

Globe and Mail: People may one day pop a pill filled with magnetized nanoparticles that will circulate through the body looking for signs of cancer. That is one of many projects being developed by Google X, a facility dedicated to exploring innovative technologies, such as the self-driving car. The cancer-detecting nanoparticles would be coated with antibodies that bind with abnormal cells. A device worn by the patient would then recall the nanoparticles and download the data they’ve gathered. Such technology could monitor an individual’s health 24/7, deliver medicine to localized areas, and detect other problems as well, such as arterial plaques. So far, the project is only in the exploratory phase.

Quantum internet may entail shipping qubits across oceans

28 October 2014

MIT Technology Review: A quantum version of the internet is being envisioned to securely transmit information. Because such a network would use entangled photons to transfer data, it would avoid the potential interference or hijacking of information that can occur during transmission through optical fibers or other conventional media. However, quantum networks will still encounter some of the same logistical problems, such as how to relay information across the oceans. Whereas quantum repeaters can extend the range of entanglement, they have been shown to work only over short distances and may prove too delicate to withstand the hostile conditions at the bottom of the sea. Now Simon Devitt from Ochanomizu University in Japan and colleagues have proposed that the quantum bits of information, or qubits, be transported across the water via container ship. Unlike conventional photons, the qubits would carry entanglement rather than actual information. Once they were in position, communication between them would be even faster than traditional repeater networks.

<em>Fermi</em> provides another potential signal of galactic dark matter

28 October 2014

New Scientist: Two previous detections of gamma rays from the center of the Milky Way have been cited as evidence of the annihilation of dark-matter particles. Now astronomers have spotted a third gamma-ray source that matches the predictions of dark-matter annihilation as well. Kevork Abazajian of the University of California, Irvine, and his colleagues predicted that starlight passing through the center of the Milky Way would scatter in a particular way off electrons produced by the annihilations.  They found evidence of just such a signal in data collected by the Fermi Gamma-Ray Space Telescope and all-sky starlight surveys. However, proving that the electrons that cause the scattering came from dark-matter annihilation is a more difficult task.

How well known is the term <em>innovation deficit</em>?

28 October 2014
Scientific and technical sophisticates use it increasingly, but what about journalists—and citizens—in general?

IR telescope captures first-ever images of nova explosion

28 October 2014

Guardian: For the first time, astronomers have captured images of a nova, a nuclear explosion on a white dwarf star. Nova Delphini 2013 was first detected last year by the CHARA Array IR telescope at Mount Wilson Observatory in Los Angeles. Such explosions are believed to occur in binary star systems, when a white dwarf is able to accrete enough hydrogen from its companion star that it ignites and starts nuclear fusion. Within hours of the explosion, astronomers were able to point the array telescopes toward the nova to take interferometric measurements of its size and expansion rate. From that data, they have determined that the nova is about 14 800 light-years from the Sun, which means the explosion occurred some 15 000 years ago. When last measured 43 days after the explosion, the nova had expanded nearly 20-fold.

Head of Nuclear Regulatory Commission resigns

28 October 2014
Just over one and a half years into a five-year term, the head of the Nuclear Regulatory Commission has said she is stepping down.

UK's Met Office plans upgrade for weather-forecasting supercomputer

28 October 2014

BBC: The UK's Met Office has confirmed that it will build a £97 million ($156 million) supercomputer to replace the one it currently uses for weather and climate modeling. The computing facility's location will be split between the Met Office's headquarters and a new facility, both in Exeter. The first computations will take place in September 2015. The Cray XC40 will have a processor speed of 16 petaflops (16 × 1015 calculations per second), 13 times faster than the current machine, and will have 17 petabytes of storage. That will allow for faster and more accurate weather forecasts as well as better and longer-scale climate models. Because of the UK's location and geography, weather forecasting is more difficult than in many other places. The Met Office estimates that improved forecasts could provide £2 billion in economic benefits.

Steady decline in US carbon emissions stalled by cold winter

27 October 2014

Ars Technica: According to the US Energy Information Administration (EIA), total US emissions of carbon dioxide rose in 2013 compared with the previous year. The rise constitutes an upward blip in a downward trend that began nine years ago. Increased economic activity was not responsible for the rise, says the EIA. Although US GDP per capita rose by 1.5% from 2012 to 2013, the gain was partly offset by increased energy efficiency. Rather, the boost in emissions resulted primarily from the unusually low temperatures of last winter, which led to increased burning of fuel oil. Another contributor was a rise in the price of natural gas, which prompted electric utilities to save money by burning more coal.

Faster ferroelectric switching

27 October 2014

MIT Technology Review: Ferroelectric materials can be made to reverse the direction of their polarization by applying an electric field. Once changed, the direction of the polarization persists, a property that has been exploited to store data. But until now, the speed at which the change occurs has been too low to rival the switching speeds attained by silicon-based transistors. A collaboration led by Lane Martin of the University of California, Berkeley, and Andrew Rappe of the University of Pennsylvania has developed a ferroelectric material, lead zirconate titanate (PbZr0.2Ti0.8O3), that can switch much faster than standard ferroelectrics. The key to the gain in speed lies in growing crystals of the material at a particular orientation, which creates two so-called side states of polarization in addition to the regular two states. The faster-switching side states can be manipulated by applying an electric field in a particular direction.

Study compares true economic costs of power sources

23 October 2014

Nature: A study commissioned by the European Union's executive branch has determined that 54% of all research papers published worldwide between 2007 and 2012 are freely accessible online. The fraction has been steadily increasing. In 1996, the start of the study period, only 28% of papers were free to read. The upward trend reflects the growing use of embargoes that liberate papers from access controls after a year or more. Also contributing to the trend is researchers' practice of posting freely accessible copies of their papers on their websites. Although the fraction of papers published in open-access journals continues to increase, those papers amounted to only 13% of the freely accessible total in 2012.

Archival research papers are increasingly free to read

23 October 2014

Nature: A study commissioned by the European Union's executive branch has determined that 54% of all research papers published worldwide between 2007 and 2012 are freely accessible online. The fraction has been steadily increasing. In 1996, the start of the study period, only 28% of papers were free to read. The upward trend reflects the growing use of embargoes that liberate papers from access controls after a year or more. Also contributing to the trend is researchers' practice of posting freely accessible copies of their papers on their websites. Although the fraction of papers published in open-access journals continues to increase, those papers amounted to only 13% of the freely accessible total in 2012.

Some superbright x-ray sources may be unusual pulsars

23 October 2014

Ars Technica: Since their discovery in the 1970s, ultraluminous x-ray sources (ULXs) continue to puzzle astronomers. At first they were thought to be stellar-sized black holes, but their luminosity exceeded a theoretical limit based on their masses. Recent observations have suggested that they are intermediate-sized black holes, with masses on the order of 100 to 100 000 times that of the Sun. But an unexpected finding about a known ULX in the M82 galaxy may complicate that possibility. Deepto Chakrabarty of MIT and his colleagues were using NASA's Nuclear Spectroscopic Telescope Array to watch the galaxy for a new supernova when they noticed that the brightness of ULX X-2 was pulsing, something that black holes don't do. Using the Chandra X-Ray Telescope, the researchers confirmed that it was in fact X-2 that was pulsing. That makes it possible that X-2 and other ULXs are pulsars—bright, rapidly rotating neutron stars—and not black holes. However, X-2 is significantly brighter than any other known pulsars. The same limit to black hole luminosity applies to pulsars, and X-2 exceeded the limit by a factor of 100. Chakrabarty recalculated X-2's mass using the version of the brightness limit that accounts for a pulsar's magnetic field and found that while the ULX's mass had increased, it was still two to three times brighter than it should be. To further confuse the situation, X-2 has a sibling, ULX X-1, that shows no sign of being a pulsar.

Modeling a virus atom by atom

23 October 2014
An ambitious calculation shows how the icosahedral protein shell interacts with the water around it.

Agents of change

22 October 2014
Sustainability in the face of climate change was the focus of a recent Smithsonian symposium celebrating the 50th anniversary of the National Tropical Botanical Garden.

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