Welcome to the Saturday Science Edition of Overnight News Digest
Overnight News Digest is a regular daily feature which provides noteworthy news items and commentary from around the world. The editorial staff includes side pocket, maggiejean, wader, Doctor RJ, rfall, and JML9999.
Neon Vincent is our editor-in-chief.
Special thanks go to Magnifico for starting this venerable series.
Astronomy
Milky Way's Black Hole Shows Signs Of Increased Chatter
Three orbiting X-ray space telescopes have detected an increased rate of X-ray flares from the usually quiet giant black hole at the center of our Milky Way galaxy after new long-term monitoring. Scientists are trying to learn whether this is normal behavior that was unnoticed due to limited monitoring, or these flares are triggered by the recent close passage of a mysterious, dusty object. By combining information from long monitoring campaigns by NASA's Chandra X-ray Observatory and ESA’s XMM-Newton, with observations by the Swift satellite, astronomers were able to carefully trace the activity of the Milky Way’s supermassive black hole over the last 15 years. The supermassive black hole, a.k.a. Sagittarius A*, weighs in at slightly more than 4 million times the mass of the Sun. X-rays are produced by hot gas flowing toward the black hole. The new study reveals that Sagittarius A* (Sgr A* for short) has been producing one bright X-ray flare about every ten days. However, within the past year, there has been a ten-fold increase in the rate of bright flares from Sgr A*, at about one every day. This increase happened soon after the close approach to Sgr A* by a mysterious object called G2. [...] Originally, astronomers thought G2 was an extended cloud of gas and dust. However, after passing close to Sgr A* in late 2013, its appearance did not change much, apart from being slightly stretched by the gravity of the black hole. This led to new theories that G2 was not simply a gas cloud, but instead a star swathed in an extended dusty cocoon.
"There isn't universal agreement on what G2 is," said Mark Morris of the University of California at Los Angeles. "However, the fact that Sgr A* became more active not long after G2 passed by suggests that the matter coming off of G2 might have caused an increase in the black hole’s feeding rate."
chandra.si.edu
O---O---O
NASA Mars Probe Marks One Year At Red Planet
NASA's newest Mars probe has now been circling the Red Planet for a year. The Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft arrived in orbit around the Red Planet on Sept. 21, 2014, 10 months after blasting off from Florida's Cape Canaveral Air Force Station. MAVEN endured a two-month checkout phase on orbit and then began studying Mars' atmosphere, in an attempt to determine how fast the planet's air is escaping into space. Such information will help researchers better understand how and when Mars shifted from a relatively warm and wet world in the ancient past to the cold and dry planet it is today, NASA officials have said. [...]
"We're obtaining an incredibly rich data set that is on track to answer the questions we originally posed for MAVEN and that will serve the planetary science community for a long time to come," MAVEN principal investigator Bruce Jakosky, of the University of Colorado's Laboratory for Atmospheric and Space Physics in Boulder, said in a statement.
space.com
O---O---O
Biology
Flower Declines Shrink Bee Tongues
Many co-evolved species have precisely matched traits; for example, long-tongued bumble bees are well adapted for obtaining nectar from deep flowers with long corolla tubes. Recent studies suggest long-tongued bumble bees are declining in number. To better understand why, Nicole Miller-Struthman et al. studied several high-altitude sites in Colorado where two species of long-tongued alpine bumble bee live. Using bumble bee specimens from 1966 through 1980, and from 2012 through 2014, the researchers measured changes in tongue length, noticing a significant shortening. Next, using archived bee specimens and field surveys of bumble bees and host plants, they examined possible mechanisms for this change. It was not a result of decreasing body size, competition from invaders, or co-evolution with flowers in the area, they report. Instead, it is a result of warming summers, which reduced numbers of the deep flowers these species preferred, forcing the insects to be general foragers capable of feeding across remaining flowers, including many shallow flowers. sciencedaily.com
O---O---O
New Study Finds Mosquitoes Thriving In Greenland
Climate change is raising temperatures globally, which influences insect physiology, growth rates and survival, including their ability to elude predators. Arctic mosquitoes develop in shallow temporary ponds of springtime snowmelt on the tundra, where their top predators are diving beetles. [...] The results show that warmer spring temperatures caused the mosquitoes to emerge two weeks early and shortened their development time through the larval and pupal stages by about 10% for every one degree Celsius increase in temperature. Warming increased the number of mosquitoes being eaten by diving beetles, but the mosquitoes’ accelerated growth in their vulnerable juvenile stages lessened their time with aquatic predators, which ultimately increased their chance of surviving to adulthood. With a 2 degrees Celsius warming scenario, the model predicts the mosquitoes’ probability of survival will increase by 53%. sci-news.com
O---O---O
Chemistry
Alkaline Flow Battery Charges Up Renewable Energy Storage
[...] Solar and wind energy resources are a growing issue for utilities as they try to match fluctuating consumer demand for electricity to the intermittent nature of renewable energy generation. In order to stop energy companies from resorting to established coal and gas infrastructure to prop up the electricity grid, many see long term energy storage as a way to effectively integrate renewables into national energy strategies. Batteries are one technology that offers an answer to this problem, but the market is flooded with different products, from lithium–ion to lead–acid cells, that are costly, potentially hazardous on an industrial scale and unable to store energy for extended periods. But there may be an alternative. ‘Flow batteries are significantly different than conventional batteries,’ comments Robert Savinell, an electrochemical energy storage expert from Case Western Reserve University, US, who was not involved in the work. ‘The reason is that they’re more adaptable for large scale energy storage.’ ‘[A flow battery] closely resembles a fuel cell where normally … you have hydrogen and oxygen gas streams entering into an energy conversion device separated by a membrane and you have two electrodes,’ explains Michael Marshak from the University of Colorado Boulder, who led the team that created the new battery. But, in the case of a flow battery a positive and negative liquid electrolyte are pumped into the cell from separate reservoirs. The positive electrolyte gives up electrons, which pass through an external circuit to combine with the negative-charged electrolyte, with cations from the electrode being free to pass through the ion-selective membrane. Following this charging process, the electrolytes can be stored in external tanks and, as the battery current flow is reversible, pumped backed through the central battery for discharging at a later time. This makes flow batteries easily scalable and adaptable, according to Marshak, as the discharge time only scales with the size of the external electrolyte reservoirs and not the number of batteries used – you only need one. rsc.org
O---O---O
Yeast-Filled Fibers Could Treat Polluted Wastewater
Olive oil may seem like a healthy, natural food. But the process of extracting it creates approximately 2 million tons of wastewater every year in Near East and Mediterranean regions, polluting water supplies and endangering fish. Now a team of scientists is proposing to use yeast embedded in fibers to digest pollutants in the wastewater and produce a usable product such as ethanol. [...] Olive oil wastewater lowers the pH level of waterways and pollutes them with phenols, which are toxic to both fish and plant life at relatively low concentrations. The yeast strain Candida tropicalis, present naturally in olive mill wastewater, breaks down phenols. But simply dumping a batch of yeast in polluted wastewater might lead to other environmental consequences, such as affecting soil bacteria, the researchers say, and might also require multiple treatments. So Ilya Letnik, J. Stefan Rokem, and Charles Greenblatt of the Hebrew University of Jerusalem, and colleagues tried encapsulating the yeast inside polymer fibers. To make the fibers, they first created two polymer solutions: one containing 20% yeast cells by volume in polyvinylpyrrolidone, and another containing a mixture of polyvinylidene fluoride-co-hexafluoropropylene and polyethylene glycol (PEG). They used electrospinning to create the fibers, ejecting a steady stream of the solutions from separate, concentric syringes under high voltage. The resulting fibers consisted of a core containing the yeast cells and an outer, insoluble polymer shell. The presence of PEG in the solution created pores in the outer shell with an average size of 40 nm, large enough to allow water, phenols, and other nutrients to pass through but too small for the yeast cells to escape. The idea is to create a filter out of the fibers, a sort of “tea bag” that can be dipped into polluted water to allow the yeast to digest phenols, says study coauthor Andreas Grenier, a macromolecular chemist at the University of Bayreuth, in Germany. “When the tea is done—in other words, when the water is clean—we pull it out again.” cen.acs.org
O---O---O
Earth Science
El Niño's Role In Pacific Ocean Sea Level Rise
Many tropical Pacific island nations are struggling to adapt to gradual sea level rise stemming from warming oceans and melting ice caps. Now they may also see much more frequent extreme interannual sea level swings. The culprit is a projected behavioral change of the El Niño phenomenon and its characteristic Pacific wind response, according to recent computer modeling experiments and tide-gauge analysis by scientists Matthew Widlansky and Axel Timmermann at the International Pacific Research Center, University of Hawaiʻi at Mānoa, and their colleague Wenju Cai at Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Australia. During El Niño, warm water and high sea levels shift eastward, leaving in their wake low sea levels in the western Pacific. Scientists have already shown that this east-west seesaw is often followed six months to a year later by a similar north-south sea level seesaw with water levels dropping by up to one foot (30 cm) in the Southern Hemisphere. Such sea level drops expose shallow marine ecosystems in South Pacific Islands, causing massive coral die-offs with a foul smelling tide called taimasa (pronounced [kai’ ma’sa]) by Samoans. El Niño and climate change combine forces The team of scientists recently asked, how will future greenhouse warming affect the El Niño sea level seesaws? The scientist used state-of-the-art climate models, which accounted for increasing greenhouse gas concentrations, together with simulations of the observed climate and tide-gauge records to verify the model results. They determined that projected climate change will enhance El Niño-related sea level extremes. By the end of this century the experiments show that the intensified wind impacts of strong El Niño and La Niña events are likely to double the frequency of extreme sea level occurrences, especially in the tropical southwestern Pacific. “From our previous work, we know that toward the end of a very strong El Niño event, the tide-gauge measurements around Guam quickly return to normal reflecting the east-west seesaw, but those near Samoa continue to drop as a result of the lagging north-south seesaw,” explains Widlansky. “During these strong events, the summer rainband over Samoa, called the South Pacific Convergence Zone, shifts toward the equator and alters the trade winds and ocean currents which in turn change the sea level.” enn.com
O---O---O
As Fires Grow, A New Landscape Appears In The West
NEAR COCHITI CANYON, N.M. — The hills here are beautiful, a rolling, green landscape of grasses and shrubs under a late-summer sky. But it is starkly different from what was here before: vast forests of ponderosa pine. The repeated blazes that devastated the trees were caused by simple things: an improperly extinguished campfire in 1996, a tree falling on a power line in 2011. What happened after the fire, however — or, more accurately, what has not happened — was a departure from the normal course of events. “We are in the middle of this 30,000-acre, near-treeless hole,” said Craig D. Allen, a research ecologist with the United States Geological Survey. If historical patterns had held, the remaining pines would by now be preparing seeds to drop and start the cycle of regrowth. But the mother pines are nowhere in sight. Nature’s script has been disrupted by a series of unusually intense, unusually large fires — a product of many factors that include government firefighting policies, climate change and bad luck. The result is bad news for forests here, in the West and around the world. A planet with fewer trees is less able to fight climate change, because trees absorb carbon dioxide from the atmosphere as part of photosynthesis. “The future in a lot of places,” Dr. Allen said, “is looking shrubbier.” nytimes
O---O---O
Physics
Shades Of 'Star Trek'? Quantum Teleportation Sets Distance Record
A record-breaking distance has been achieved in the bizarre world of quantum teleportation, scientists say. The scientists teleported photons (packets of light) across a spool of fiber optics 63 miles (102 kilometers) long, four times farther than the previous record. This research could one day lead to a "quantum Internet" that offers next-generation encryption, the scientists said. [...] Quantum teleportation depends on capturing the fundamental details of an object — its "quantum states" — and instantly transmitting that information from one area to another to recreate the exact object someplace else. Quantum teleportation relies on the strange nature of quantum physics, which finds that the fundamental building blocks of the universe can essentially exist in two or more places at once. Specifically, quantum teleportation relies on an odd phenomenon known as "quantum entanglement," in which subatomic particles can become linked and influence each other instantaneously, regardless of how far apart they are. Scientists cannot distinguish the state of either particle until one is directly measured, but because the particles are connected, measuring one instantly determines the state of the other. [...] The new distance record was set using advanced single-photon detectors made of superconducting wires of molybdenum silicide that were about 150 nanometers (or billionths of a meter) wide and cooled to about minus 457 degrees Fahrenheit (minus 272 degrees Celsius), or about 1 degree above absolute zero. The experiment involved a near-infrared wavelength commonly used in telecommunications, the researchers said. livescience.com (h/t Shockwave)
O---O---O
Spinning ring on a table found to behave more like a boomerang than a coin
A trio of researchers, two with the University of California, the third with Sharif University of Technology, in Iran, has found that a common ring, such as is worn on the finger, spins differently on a tabletop than does a coin. In their paper published in Physical Review E, Mir Abbas Jalali, Milad Sarebangholi and Reza Alam describe their tests and observations and offer a theory on why a spinning ring behaves the way it does. If you use your fingers to spin a coin on a tabletop, it will tend to move around on the table in the same direction that it is spinning until it stops. That is not the case with a spinning ring, the researchers found (first by simply noticing it and then via testing). Unlike the movement of the coin, the ring will move first in the direction of its spin, but then will stop moving and reverse itself, moving against its own spin. A coin, the researchers note, tends to spin in the same direction as its spin due to friction—and that appears to be the case with a ring as well. Both also, at least initially spin atop a thin layer of air that gets trapped beneath one of its edge and the tabletop. But, because the ring, which is essentially the same thing as a coin except for the large hole in it, has that hole, the trapped air can escape. When it does, the researchers theorize, the frictional forces change, resulting in the ring stopping and changing directions. Intrigued by the odd movement of the spinning ring, and surprised that they could not find any description or study of it in the literature, the researchers set about studying the phenomenon in their lab. They created coins by cutting metal rods and rings by cutting metal tubes, both of a variety of different sizes and thicknesses and then set them to spinning while recording with a high-speed camera.
YouTube Video
In studying the video, it became apparent to the researchers that the change in direction came about due to the change in air flow. They also discovered that the reverse-effect occurred with all of the rings they tested, suggesting the behavior is both consistent and replicable, traits they suggest, that might be useful when designing objects that move on topologically flat surfaces, especially those that require complicated reorientations or automatic reversals. phys.org