Physics Today Daily Edition
Daily Mail: A new type of flying vehicle has been developed by Elytron Aircraft. The new craft combines the vertical take-off and landing capabilities of a helicopter with the speed and efficiency of a fixed-wing airplane. The design features three sets of wings: one pair of rotary wings, called “proprotors,” positioned between two pairs of fixed wings—one forward and one aft—joined with winglets. The new aircraft is more fuel-efficient and has greater range than rotary-wing craft but can take off and land without a long runway. Hence, the company says, it could be used in various capacities, including “emergency medical services, search and rescue, air taxi, and oil exploration.” A two-seater demonstration model will be on display next week at EAA Airventure Oshkosh.
NPR: Plastic food packaging involves more science and innovation than one might think. Lighter than glass, more durable than paper, and relatively cheap to produce, the plastic used in the food industry is actually an amalgam of several different types. Take a bag of potato chips: The bag may have as many as three layers—an exterior layer of polypropylene, which serves as a moisture barrier; an inner layer of thin aluminum coating, which strengthens the bag; and a layer of another plastic called polyethylene sandwiched in between. Besides the potato chips, the bags may also get a shot of nitrogen gas before they are sealed, which helps prevent the chips from getting crushed. The type of packaging used depends on the type of food inside, since some materials can cause chemical reactions and affect the product's flavor. Because all the nifty packaging creates a lot of extra waste, however, researchers are now working to create new plastics that are also environmentally friendly.
Los Angeles Times: Physicists, engineers, and other scientists are discovering an alternative to the more traditional career paths in aerospace and academia: the movie industry. One physicist who has made the switch is Ron Henderson, a former Caltech faculty member who specializes in fluid dynamics. Henderson now works for DreamWorks Studios, where he devises complex algorithms to simulate natural phenomena, such as water and fire, for animated films. He has even won an award from the Academy of Motion Picture Arts and Sciences for his development of a fluid-simulation system called Flux. He says that besides the potential to make more money, the film business offers the challenge of finding solutions to technical problems and the opportunity to work as part of a team with people from many different backgrounds. One of Henderson’s most recent projects was to create computer-animated simulations of bubble-like spheres for tiny aliens to live in for a short, animated film titled Home.
Science: NASA has invited submissions for instrument designs to be included on the proposed Clipper mission to Europa. The agency will choose 15 to 20 of the submissions, each of which will receive $1.25 million for further development. Of those, eight finalists will be chosen for inclusion in the final satellite construction. NASA is targeting a launch in the mid 2020s. Whether the project receives funding from Congress is still an open question. NASA estimates that Clipper will require $2 billion to $3 billion.
New York Times: In 2011, less than 1% of the world's total electricity came from geothermal plants. In 2013, geothermal energy production grew to nearly 5% and is poised to grow further, especially in Indonesia, Africa, and parts of Central and South America. Currently the largest producer of geothermal energy is the US, followed by the Philippines, Indonesia, and Mexico. The growth of geothermal energy has been slow because of high upfront costs and the difficulty in identifying where to drill. Whereas most of a plant's cost (50–60%) is incurred in drilling the wells, about 10–30% of the test wells are not usable. The recent growth of the industry has been aided by the spread of hydraulic fracturing. The development of fracking as a viable method for oil and gas extraction has advanced drilling technology that can also be applied to geothermal wells.
SciDev.Net: The most recent version of the United Nations’ Sustainable Development Goals (SDGs) lays out 169 targets spread across 17 goals. The report is the result of 13 working group meetings over some 16 months. However, scientists say many of the scientifically quantified targets of earlier versions have been removed. Two of the targets that pertain to climate change—zero biodiversity loss and a two-degree Celsius limit for temperature rise—and that appeared in earlier versions are essential, according to Johan Rockström, executive director of the Stockholm Resilience Centre in Sweden. “What politicians need to recognise is that if you lock yourself to these two targets, the methods to achieve these force you to address most other environmental challenges,” he said. Among those who disagree is Guido Schmidt-Traub, executive director of the UN initiative Sustainable Development Solutions Network. He says that although such targets should be considered, the most important thing is to trim the overall document down to a manageable list of goals and targets. The report is scheduled to be reviewed by the UN General Assembly in September.
Science: Blue whales—the largest animals known to have existed on Earth ever—were hunted almost to extinction in the 20th century. Although a 1966 ban on whaling helped many whale species rebound, the number of blue whales has not increased as much as expected. According to a study published this week in the journal PLOS One, a contributing factor may be collisions with ships. The researchers tagged and tracked blue whales off the coast of California. They found that a significant number of them were being struck and killed by ships traveling between the busy ports of San Francisco and Los Angeles. As a result, the National Oceanic and Atmospheric Administration will be reviewing the situation to find a solution, which could include speed restrictions on vessels or alterations to the commercial shipping lanes, especially during the summer at the height of the whales’ feeding season.
Science: The observation that Antarctic sea ice appears to be expanding seems to run counter to the fact that Earth’s climate is growing warmer. To find out why, Ian Eisenman of the Scripps Institution of Oceanography in San Diego, California, and colleagues decided to look more closely at the data behind the 2007 and 2013 reports from the Intergovernmental Panel on Climate Change. In comparing them, the researchers found that the data had been recalibrated several times to ensure continuity from one satellite to the next over time and that discrepancies existed between the two different versions of the algorithm used to process the data. While it does indeed appear that Antarctic sea ice is expanding overall, the expansion varies regionally and seasonally, and in some places the ice is actually retreating. It is that complex spatial pattern that researchers seek to understand, and more thorough satellite data calibration methods may be needed to do so.
Los Angeles Times: Although bats rely largely on echolocation for finding their way around, it only works over relatively short distances. For longer flights, bats have been known to use other cues, such as visible light and Earth’s magnetic field. Now researchers have found that bats also use polarized light—sunlight that has been scattered and refracted as it passes through Earth’s atmosphere yet is invisible to humans. To test that theory, Stefan Greif of the Sensory Ecology Group at the Max Planck Institute for Ornithology and colleagues put adult female greater mouse-eared bats in special boxes with windows. By covering the windows with filters, they were able to manipulate the sky’s natural polarization patterns. They found that the bats that experienced the light manipulation flew off in directions 90 degrees to those of the control group. The researchers have determined that polarization does not give direction but rather helps the bats calibrate their internal magnetic compass. Finding out how the bats perceive polarized light is the scientists' next task.
Space.com: Whereas the Cold War motivated the US to put a man on the Moon, it has been more than four decades since any other similar manned missions have been undertaken. While the US has been considering missions to other destinations, including Mars and an asteroid, countries such as China, India, Iran, Japan, and Russia have been revisiting the idea of exploring the Moon. Now some scientists in the US are also pushing for the Moon because of its proximity to Earth. At just three days’ travel, they say, the Moon is the most viable location for a semipermanent research base and space colonization efforts, since it would be much easier to restock supplies and mount potential rescue operations. In addition, because of the rising costs involved, future missions will probably require international cooperation, and the Moon offers the best prospects for that.
NPR: Scientists at Harvard University have found a cheap alternative to glass test tubes: the plastic packaging material known as bubble wrap. George Whitesides, who led the study, says he got the idea while traveling to different labs around the world. Scientists in developing countries struggle to obtain even the simplest pieces of equipment, such as test tubes. Bubble wrap, however, is everywhere, and it is often found in labs because it’s used for shipping equipment. While experimenting with bubble wrap, Whitesides and colleagues injected samples of blood and chemicals into the individual bubbles with a syringe and sealed the hole with nail polish. They found that not only do the bubbles work well to store liquid samples but they are also sterile. Although Whitesides recognizes that bubble wrap has its drawbacks—the bubbles pop easily and are sensitive to light—he hopes the idea will serve to inspire people to find innovative uses for other inexpensive, everyday materials.
Science: On Friday the US Senate released its working draft of the America COMPETES Reauthorization Act of 2014. Among its provisions, the bill recommends increasing the funding of NSF over the next five years, supports NSF’s continued management of its research grants, and emphasizes the importance of the social, behavioral, and economic sciences. In contrast, the House bill would only fund NSF over the next year and would cut funding for the social sciences. Senator Jay Rockefeller (D-WV) believes the Senate bill is better because it relies on scientists, rather than politicians, to allocate science funding. The process of reconciling the two bills is expected to be a lengthy one and may well extend into next year.
Nature: In 2012, Stefan Gillessen of the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, and his colleagues spotted a gas cloud approaching Sagittarius A*, the black hole at the center of the Milky Way. It appeared that part of the cloud would get pulled off and hit the accretion disk that swirls around the black hole. The resulting collision would have created a large explosion of radiation. But that didn't happen. As Gillessen's team continued observing, they also looked at older data and found a second cloud of gas following the same path. They believe that means that the two clouds are actually part of a larger stream of gas, possibly pulled from a star that passed near Sagittarius A* within the last 100 to 200 years. Another group of researchers suggests that a star is hidden within the gas cloud and that the star's gravitation is what kept the cloud from fragmenting and falling into the black hole.