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Updated: 3 hours 37 min ago

Clouds may not slow global warming as much as thought

11 April 2016
New York Times: Clouds can consist of tiny liquid water droplets, tiny ice crystals, or both. In a recent study, researchers concentrated on mixed-phase clouds and their effect on global warming. The scientists found that such clouds have more water and less ice than expected, and that the water–ice ratio will continue to grow as the atmosphere warms. Although water droplets reflect more solar radiation back into the sky than ice crystals do, the fact that there is less ice to begin with may reduce the clouds’ cooling effect. The researchers caution that there is still a high level of uncertainty in exactly how much loss there will be in such clouds’ cooling power, but the findings mean it will almost certainly be harder to keep global warming to the 2 °C limit set by the Intergovernmental Panel on Climate Change.

Study shows ribose could be formed on ice in space

11 April 2016
New Scientist: Ribose is the molecule at the backbone of RNA. But unlike many other building blocks of living cells, such as amino acids, ribose has never been found in samples from meteorites or created outside of cells in laboratories. Now Cornelia Meinert of the University of Nice Sophia Antipolis in France and her colleagues have created ribose in a lab by exposing frozen water, methanol, and ammonia—chemicals widely present in the early solar system—to UV light. A similar project by Scott Sandford of NASA's Ames Research Center in California has also found success. Whether sugars such as ribose could actually form in space is still an open question, but the two teams have shown that a formation process is viable. It is possible that molecules of ribose have been preserved on distant, cold objects where they haven't been broken apart by the Sun's radiation; simpler sugars have already been found on comets. A cosmic recipe for ribose helps support the possibility that many of the building blocks of life emerged during the formation of the solar system.

Panasonic weather model strives to outperform government forecasting centers

11 April 2016

Ars Technica: A new model in the weather forecasting field is working to surpass the two current global contenders—the US Global Forecasting System and the European Center for Medium Range Weather Forecasting. Over the past several years, multinational electronics company Panasonic has been using weather information gathered by airplanes to develop its own global weather forecasting model. Sensors mounted on private aircraft have been collecting data on wind, temperature, and other weather parameters since the 1990s, when the Clinton administration instituted the policy to monitor potentially dangerous conditions during flight. Panasonic acquired that weather monitoring system, called TAMDAR, in 2013 and created its own weather forecasting unit, Panasonic Weather Solutions (PWS). Neil Jacobs, the company’s chief atmospheric scientist, claims that PWS has now surpassed its government competitors in accuracy, but experts say it is too soon to pass judgment. They say more forecasts will have to be made publicly available over the coming months before a just comparison can be made.

Unexpected supermassive black hole may be most massive found

11 April 2016

NPR: Supermassive black holes are at least millions of times as massive as the Sun and are commonly found at the center of large galaxies. The very largest known black holes, which can be a billion times as massive as the Sun, have only been found in dense clusters of very large galaxies. Those behemoths are thought to form when two black holes merge in a galactic collision. A newly discovered supermassive black hole challenges the idea that such collisions are only likely in dense clusters. Found in a relatively inactive group of average-sized galaxies, the black hole has a mass of about 17 billion Suns. Its unusual location suggests that such gargantuan black holes may be more common than previously thought.

Solar cells with graphene layer could generate electricity from rain

11 April 2016

IEEE Spectrum: Solar cells generate minimal electricity when it's cloudy or raining, but the rain does serve a purpose: It rinses dust off the cells. Now Qunwei Tang of Ocean University of China in Qingdao and his colleagues have succeeded in using the ionized salts in rain to keep solar cells generating electricity even when the weather is inclement. To attract the positively charged ions and induce a capacitor-like effect, Tang's team added a layer of graphene to an inexpensive thin-film solar cell mounted on a flexible backing. When slightly salty water was sprayed on the solar cells, they generated hundreds of microvolts of electricity, achieving a solar-to-electric conversion efficiency of 6.53%. Tang says that the proof of concept shows that solar cells could be adapted to generate electricity in all kinds of weather.

Questions and answers with Shing-Tung Yau

11 April 2016
The esteemed mathematician says China can get a far greater return from hosting a 100 TeV “Great Collider” than from its investment in the 2022 Winter Olympics.

Computer creates its own Rembrandt-style painting

11 April 2016

BBC: A new masterpiece has been created in the style of Dutch master painter Rembrandt—but not by human hands. Over the past two years Microsoft and others have been collaborating on a project to develop a computer program that can paint an original Rembrandt-style portrait. The researchers made three-dimensional scans of Rembrandt’s paintings and digitally tagged data on everything from content to lighting to brush-stroke style. Then machine-learning algorithms looked for characteristic patterns in the data. Finally, the computer was asked to create its own portrait in the style of Rembrandt. The final image was 3D printed using 13 layers of ink to replicate the height and depth of the paint in an actual Rembrandt work. The result, a remarkably realistic-looking painting of a middle-aged white male in period dress, is to be put on public exhibition and will be used to better understand “what makes a masterpiece a masterpiece,” said Emmanuel Flores, the project’s technology director.

Fine-tuning our view of how language changes

7 April 2016
A new mathematical tool distinguishes commonly used words from those used infrequently.

Emails reveal details of elimination of Australian climate science positions

6 April 2016
Guardian: After Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO) cut 120 climate science jobs in early February, the organization's executives claimed that the decision was not part of an effort to move away from "public-good science." Now the release of 700 pages of emails and other documents, as part of an investigation into federal budget cuts, suggests that the opposite was true. One email stated that CSIRO executives wanted climate scientists to focus on research that is "linked to jobs and growth" and "not doing science for science sake." Another email advised how many employees to let go to "allow a clean cut in terms of eliminating all capability associated with 'public good/government-funded climate research.'" In March, addressing a Senate inquiry, CSIRO executive director of environment, energy, and resources Alex Wonhas categorically denied that cutting public-good research was a guiding principle for determining which jobs were eliminated.

Iron isotope reveals Earth’s close encounters with supernovae

6 April 2016
Three new studies associate iron-60 deposits with nearby stellar explosions that occurred as recently as 1.5 million years ago.

Livermore National Lab to test IBM's brain-inspired computer chip

6 April 2016

IEEE Spectrum: Six years ago, IBM began work on a highly parallelized, low-energy computer chip—dubbed TrueNorth—that was inspired by the behavior of the human brain. In 2014, researchers completed the first of those 5.4-billion-transistor chips, which consume just 70 mW of electricity at peak operation. Now, the company has combined 16 of the chips into a single computer and sent it to Lawrence Livermore National Laboratory for testing. Researchers at the lab, which is home to several of the world's fastest supercomputers, will evaluate the technology to determine its potential usefulness for a variety of applications, particularly pattern recognition. Because supercomputers consume a lot of energy, the fact that TrueNorth uses significantly less power than conventional computer chips, even when it works on the most difficult tasks, could make it a key component in the development of exascale computing.

NASA group to conduct snow census from the air

6 April 2016
Nature: Although snowfall is important for replenishing an area’s water resources, it has proven difficult to accurately measure because of the variety of landscapes it covers, such as mountains, prairies, and tundra. To come up with better measurement and modeling techniques, NASA has been developing SnowEx, an experiment that uses aircraft equipped with radar, lidar, and other remote-sensing instruments to measure snow cover. Starting this fall, the sensors will be tested simultaneously over various sites in North America to see which combination is most effective. The project may expand beyond the continent in future years. The ultimate goal is to build a snow-sensing satellite fitted with the best combination of sensing technologies. Scientists want more accurate information on snowfall and the expected melt and runoff connected to climate change.

Space station to add inflatable room

6 April 2016
New Scientist: The astronauts on the International Space Station (ISS) are about to get a new room. An inflatable module is scheduled to be launched on 8 April as part of a SpaceX resupply mission. Made of a soft, foldable fabric, the Bigelow Expandable Activity Module (BEAM), developed by Bigelow Aerospace, will be packed into the trunk compartment of the Dragon spacecraft. Once in orbit, the fabric will be attached to node 3 of the ISS and allowed to expand. Over the next two years, BEAM will remain unoccupied but will be monitored for pressure and temperature, radiation protection, and potential deterioration from meteoroid or debris impacts. Astronauts will also periodically enter the module and inspect it. If the technology works, Bigelow hopes to use it for larger projects, such as a private space station or space hotel.

White House highlights water R&D needs

5 April 2016
Dozens of US universities and private-sector entities join federal agencies to mark World Water Day.

SLAC particle accelerator to add second x-ray laser

5 April 2016
Ars Technica: SLAC National Accelerator Laboratory, the most powerful x-ray source in the world, has announced it is undertaking a $1 billion upgrade in partnership with four other national labs and Cornell University. SLAC plans to add a second x-ray laser that will be 10 000 times as bright and fire 8000 times as fast as the existing Linac Coherent Light Source. Whereas LCLS generates 120 laser pulses per second by accelerating electrons down a copper pipe, LCLS-II is expected to achieve one million pulses per second by the addition of a superconducting accelerator. Designed to work in parallel, the two lasers will allow researchers to make more detailed observations of samples and to gather data more quickly.<

DNA used to craft world's smallest diode

5 April 2016

IEEE Spectrum: Diodes are electrical components that allow electricity to flow in only a single direction. Now a diode has been made from an 11-base-pair length of DNA combined with two molecules of coralyne. The combined molecule, which is roughly 4 nm long, allows electrical current to flow through it 15 times as strongly in one direction as in the other. The researchers believe that the coralyne molecules fuel the one-way movement of electricity by creating an imbalance in the distribution of electrons in the DNA.

Blue Origin rocket completes another launch and landing

5 April 2016
Wired: On 2 April, private aerospace company Blue Origin completed another successful launch of its New Shepard reusable spacecraft. This time the company was testing its BE-3 engine, which needs to start fast and provide high thrust in order to slow the craft as it returns for landing. After soaring to a height of 103 km, the rocket returned to its launch site in western Texas, where the BE-3 kicked in 1000 m—and just 6 seconds—above the ground and slowed the craft to less than 5 mph for landing. If future test flights are as successful as this one, Blue Origin CEO Jeff Bezos says the company could start offering suborbital tourist spaceflights on New Shepard as early as 2018.

Sea-level rise threatens NASA facilities

5 April 2016
New York Times: NASA owns about $32 billion worth of structures and facilities in the US. Roughly two-thirds of the land it manages is within 4.8 m of mean sea level—including Johnson Space Center in Texas, Michoud Assembly Facility in New Orleans, Ames Research Center near San Francisco Bay, and, of course, Kennedy Space Center in Florida. According to the agency's Climate Adaptation Science Investigators working group, sea-level rise by 2050 could cause those facilities significant problems, including regular flooding and increased damage from hurricanes. The agency has already spent $3 million repairing protective dunes around Kennedy Space Center, but longer-term plans for relocating and protecting facilities will likely reach into the billions.

Martian dust devils may get a boost from their own shadows

4 April 2016

New Scientist: Due to Mars's thin atmosphere, dust devils require strong winds to keep the sand grains swirling off the ground. Gerhard Wurm of the University of Duisburg-Essen in Germany suggests that the temperature difference between shadowed and sunlit ground may be enough to kick extra dust into the air. To test his theory, he dropped a capsule full of Mars-like sand down a 110 m drop tower, shined a laser light on the dust as it fell, and measured the dust grains as they bounced around inside. When Wurm switched off the laser, he noted that the grains' movement increased by a factor of 10, which he attributed to the cooling of the dust. He says that on Mars the dust devil's shadow could have a similar cooling effect. The resulting temperature changes could cause gases in the Martian soil to move around and, after a buildup of pressure, explode and lift sand into the air. That feedback effect could fuel the large dust storms occasionally seen on Mars.

Using light to transfer heat between objects

4 April 2016
IEEE Spectrum: Besides conduction and convection, a third option for transferring thermal energy is light. Although once thought too weak to be useful, heat transfer via radiation works well when the two objects transferring energy are placed close together, say Michal Lipson of Columbia University and her colleagues. Despite the difficulty involved in maintaining large thermal gradients over nanometer-scale distances, the researchers have succeeded by using high-precision microelectromechanical systems to separate nano-sized beams of silicon carbide. When the SiC beams were spaced 42 nm apart, the researchers achieved a heat transfer almost 100 times as strong as that predicted by conventional thermal radiation laws. The technology could have many uses, including converting the waste heat in a car’s combustion engine to electricity and controlling the temperature of delicate nanodevices.

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