Posts by AltonParrish:
Antarctic Coastline Images Show Four Decades of Ice Loss to Ocean
June 2nd, 2016By Alton Parrish.
Part of Antarctica has been losing ice to the ocean for far longer than had been expected, satellite pictures reveal.
A study of images along 2000 kilometers (1,240 miles) of West Antarctica’s coastline has shown the loss of about 1000 square kilometers (about 390 square miles) of ice – an area equivalent to the city of Berlin – over the past 40 years.
Researchers were surprised to find that the region has been losing ice for such a length of time. Their findings will help improve estimates of global sea level rise caused by ice melt, they said.
A research team from the University of Edinburgh analyzed hundreds of satellite photographs of the ice margin captured by NASA, the United States Geological Survey (USGS) and the European Space Agency (ESA). The study has been accepted for publication in Geophysical Research Letters, a journal of the American Geophysical Union.
They found that ice has been retreating consistently along almost the entire coastline of Antarctica’s Bellingshausen Sea since satellite records began.
“We knew that ice had been retreating from this region recently but now, thanks to a wealth of freely available satellite data, we know this has been occurring pervasively along the coastline for almost half a century,” said Frazer Christie, a PhD student in the University of Edinburgh’s School of GeoSciences, who co-led the study.
The team also monitored ice thickness and thinning rates using data taken from satellites and the air. This showed that some of the largest changes, where ice has rapidly thinned and retreated several miles since 1975, correspond to where the ice front is deepest.
Scientists suggest the loss of ice is probably caused by warmer ocean waters reaching Antarctica’s coast, rather than rising air temperatures. They say further satellite monitoring is needed to enable scientists to track progress of the ice sheet.
“This study provides important context for our understanding of what is causing ice to retreat around the continent,” said Robert Bingham, reader in Glaciology and Geophysics and a chancellor’s fellow at the University of Edinburgh’s School of GeoSciences and a co-author of the study. “We now know change to West Antarctica has been longstanding, and the challenge ahead is to determine what has been causing these ice losses for so long.”
Their study was carried out in collaboration with Temple University in Philadelphia. It was supported by the Carnegie Trust for the Universities of Scotland, the Natural Environment Research Council and the ESA.
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Fish Power? Electric Ray’s Organ Provides Power To Generator
June 1st, 2016
By Alton Parrish.
The electric ray may be the most electrosensitive of all animals. Their eyes are situated on the top of their heads, resulting in poor vision that must be compensated for with the use of other senses, including the detection of electricity. Many species of rays and skates outside the family have electric organs located in the tail; however, the electric ray possesses two large electric organs on each side of its head, where current passes from the lower to the upper surface of the body. The organs are governed by four central nerves from each side of the electric lobe, or specialized brain lobe, which is of a different color from the rest of the brain.
Scientists from the RIKEN Quantitative Biology Center in Japan removed the electric organ from a torpedo and chemically stimulated the organ by injecting a solution of the neurotransmitter acetylcholine though a syringe. They were able to achieve more than a minute of continuous current, with a peak voltage of 91 mV and 0.25 mA of current. By increasing the number of syringes, they achieved a peak voltage of 1.5 V and a current of 0.64mA.
The environmental impact of electric power generation is a pressing international concern. There are mandates to reduce the environment impact of power generation, leading to a push away from conventional thermal and nuclear power. Recently, biofuel cells such as glucose fuel cells and microbial fuel cells have been developed to meet these mandates. However, the performance of these fuel cells remains inferior to conventional systems.
They began by looking at what happens in a live electric ray. Tanaka says, “When we used physical stimulation of a live torpedo, we detected less than 10 milliseconds of pulse current with a peak voltage 19 V and current of 8 A in the electrical response. Using this pulse, we found that we were able to store enough electricity to light up LED light or drive a toy car.”
Then, in an attempt to generate more electricity, they removed the electric organ from a torpedo and chemically stimulated the organ by injecting a solution of the neurotransmitter acetylcholine though a syringe. They were able to achieve more than a minute of continuous current, with a peak voltage of 91 mV and 0.25 mA of current.
Tanaka continues, “By increasing the number of syringes, we achieved a peak voltage of 1.5 V and a current of 0.64mA. In addition, we found that it is possible to repeat power generation and keep the organ functional for up to one day.” By combining a fluid control device to control the stimulation as is done by the torpedo’s own nervous system, they were able to generate and store electricity with a peak voltage of 1.5 V and 0.25 mA of current.
Tanaka says he hopes the research will be a first step towards a future high-efficiency power generator that uses ATP directly and could lead to a modern, ultra-clean electric power generator.
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Truly Giant Stars at the Heart of Vulpecula OB1 and 80,000 Suns’ Worth of Dust
June 1st, 2016By Alton Parrish.
New stars are the lifeblood of our galaxy, and there is enough material revealed by this Herschel infrared image to build stars for millions of years to come.
Situated 8,000 light-years away in the constellation Vulpecula — Latin for “little fox” — the region in the image is known as Vulpecula OB1. It is a “stellar association” in which a batch of truly giant “OB” stars is being born. O and B stars are the largest stars that can form.
The giant stars at the heart of Vulpecula OB1 are some of the biggest in the galaxy. Containing dozens of times the mass of the sun, they have short lives, astronomically speaking, because they burn their fuel so quickly. At an estimated age of 2 million years, they are already well through their lifespans. When their fuel runs out, they will collapse and explode as supernovas. The shock this will send through the surrounding cloud will trigger the birth of even more stars, and the cycle will begin again.
O stars are at least 16 times more massive than the sun, and could be well over 100 times as massive. They are anywhere from 30,000 to 1 million times brighter than the sun, but they only live up to a few million years before exploding. B-stars are between two and 16 times as massive as the sun. They can range from 25 to 30,000 times brighter than the sun.
OB associations are regions with collections of O and B stars. Since OB stars have such short lives, finding them in large numbers indicates the region must be a strong site of ongoing star formation, which will include many more smaller stars that will survive far longer.
The vast quantities of ultraviolet light and other radiation emitted by these stars is compressing the surrounding cloud, causing nearby regions of dust and gas to begin the collapse into more new stars. In time, this process will “eat” its way through the cloud, transforming some of the raw material into shining new stars.
The image was obtained as part of Herschel’s Hi-GAL key-project. This used the infrared space observatory’s instruments to image the entire galactic plane in five different infrared wavelengths.
These wavelengths reveal cold material, most of it between -220º C and -260º C. None of it can be seen in ordinary optical wavelengths, but this infrared view shows astronomers a surprising amount of structure in the cloud’s interior.
The surprise is that the Hi-GAL survey has revealed a spider’s web of filaments that stretches across the star-forming regions of our galaxy. Part of this vast network can be seen in this image as a filigree of red and orange threads.
In visual wavelengths, the OB association is linked to a star cluster cataloged as NGC 6823. It was discovered by William Herschel in 1785 and contains 50 to 100 stars. A nebula emitting visible light, catalogued as NGC 6820, is also part of this multi-faceted star-forming region.
In other new images from the Herschel space observatory reveal huge filamentary structures of gas and dust showing how matter is distributed across our Milky Way galaxy. Long and flimsy threads emerge from a twisted mix of material, taking on complex shapes.
This image shows a filament called G49, which contains 80,000 suns’ worth of mass. This huge but slender structure of gas and dust extends about 280 light-years in length, while its diameter is only about 5 light-years across
In this image, longer-wavelength light has been assigned visible colors. Light with wavelengths of 70 microns is blue; 160-micron light is green; and 350-micron light is red. Cooler gas and dust are seen in red and yellow, with temperatures as low as minus 421 degrees Fahrenheit (minus 252 degrees Celsius).
In the densest and coolest clumps, the seeds of new generations of stars are taking shape. A brighter clump of matter is visible at the left tip of the wispy thread.
This filament is about 18,000 light-years away. The image is oriented with northeast toward the left of the image and southwest toward the right.
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Planet 9 Is an Alien World Stolen from Another Star by Our Sun
May 31st, 2016By Alton Parrish.
Caltech researchers found evidence of a giant planet tracing a bizarre, highly elongated orbit in the outer solar system. The object, which the researchers have nicknamed Planet Nine, has a mass about 10 times that of Earth and orbits about 20 times farther from the sun on average than does Neptune (which orbits the sun at an average distance of 2.8 billion miles). In fact, it would take this new planet between 10,000 and 20,000 years to make just one full orbit around the sun.
Through a computer-simulated study, astronomers at Lund University in Sweden show that it is highly likely that the so-called Planet 9 is an exoplanet. This would make it the first exoplanet to be discovered inside our own solar system. The theory is that our sun, in its youth some 4.5 billion years ago, stole Planet 9 from its original star.
An extrasolar planet, or exoplanet, is by definition a planet located outside our solar system. Now it appears that this definition is no longer viable. According to astronomers in Lund, there is a lot to indicate that Planet 9 was captured by the young sun and has been a part of our solar system completely undetected ever since.
“It is almost ironic that while astronomers often find exoplanets hundreds of light years away in other solar systems, there’s probably one hiding in our own backyard”, says Alexander Mustill, astronomer at Lund University.
Stars are born in clusters and often pass by one another. It is during these encounters that a star can “steal” one or more planets in orbit around another star. This is probably what happened when our own sun captured Planet 9.
In a computer-simulated model, Alexander together with astronomers in Lund and Bordeaux has shown that Planet 9 was probably captured by the sun when coming in close contact while orbiting another star.“Planet 9 may very well have been ‘shoved’ by other planets, and when it ended up in an orbit that was too wide around its own star, our sun may have taken the opportunity to steal and capture Planet 9 from its original star. When the sun later departed from the stellar cluster in which it was born, Planet 9 was stuck in an orbit around the sun”, says Alexander Mustill.
“There is still no image of Planet 9, not even a point of light. We don’t know if it is made up of rock, ice, or gas. All we know is that its mass is probably around ten times the mass of earth.”It requires a lot more research before it can be ascertained that Planet 9 is the first exoplanet in our solar system. If the theory is correct, Alexander Mustill believes that the study of space and the understanding of the sun and the Earth will take a giant leap forward.
“This is the only exoplanet that we, realistically, would be able to reach using a space probe”, he says.
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Caltech’s Konstantin Batygin, an assistant professor of planetary science, and Mike Brown, the Richard and Barbara Rosenberg Professor of Planetary Astronomy, discuss new research that provides evidence of a giant planet tracing a bizarre, highly elongated orbit in the outer solar system.
The six most distant known objects in the solar system with orbits exclusively beyond Neptune (magenta) all mysteriously line up in a single direction. Also, when viewed in three dimensions, they tilt nearly identically away from the plane of the solar system. Batygin and Brown show that a planet with 10 times the mass of the earth in a distant eccentric orbit anti-aligned with the other six objects (orange) is required to maintain this configuration.
The researchers, Konstantin Batygin and Mike Brown, discovered the planet’s existence through mathematical modeling and computer simulations but have not yet observed the object directly.
“This would be a real ninth planet,” says Brown, the Richard and Barbara Rosenberg Professor of Planetary Astronomy. “There have only been two true planets discovered since ancient times, and this would be a third. It’s a pretty substantial chunk of our solar system that’s still out there to be found, which is pretty exciting.”
Brown notes that the putative ninth planet—at 5,000 times the mass of Pluto—is sufficiently large that there should be no debate about whether it is a true planet. Unlike the class of smaller objects now known as dwarf planets, Planet Nine gravitationally dominates its neighborhood of the solar system. In fact, it dominates a region larger than any of the other known planets—a fact that Brown says makes it “the most planet-y of the planets in the whole solar system.”
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Computer to Train Dogs Autonomously Based on Dog’s Body Language
May 31st, 2016By Alton Parrish.
North Carolina State University researchers have developed and used a customized suite of technologies that allows a computer to train a dog autonomously, with the computer effectively responding to the dog based on the dog’s body language.
“Our approach can be used to train dogs efficiently and effectively,” says David Roberts, an assistant professor of computer science at NC State and co-author of a paper on the work. “We use sensors in custom dog harnesses to monitor a dog’s posture, and the computer reinforces the correct behavior quickly and with near-perfect consistency.”
“Because the technology integrates fundamental principles of animal learning into a computational system, we are confident it can be applied to a wide range of canine behaviors,” says Alper Bozkurt, an assistant professor of electrical and computer engineering and co-author of the paper. “For example, it could be used to more quickly train service dogs. Ultimately, we think the technology will be used in conjunction with human-directed training.”
The dog harness fits comfortably onto the dog and is equipped with a variety of technologies that can monitor the dog’s posture and body language. Each harness also incorporates a computer the size of a deck of cards that transmits the sensor data wirelessly. The researchers published a paper about the harness’s potential applications in late 2014.
For the current study, the researchers wrote an algorithm that triggered a beeping sound and the release of dog treats from a nearby dispenser whenever the dog’s harness sensors detected that the dog went from standing to sitting.
The researchers had to ensure that the reinforcement was given shortly after the desired posture was exhibited, and also ensure that rewards were only given for the correct posture. This required a trade-off. If the algorithm ran long enough to ensure the correct posture with 100 percent certainty, the reinforcement was given too late to be effective for training purposes. But if the reinforcement was given immediately, there was a high rate of rewarding the wrong posture.
To address this, the researchers worked with 16 volunteers and their dogs to optimize the algorithm, finding the best possible combination of speed and accuracy. The researchers then compared the algorithm’s timing and accuracy to that of an expert human trainer.
The algorithm was highly accurate, rewarding the appropriate behavior 96 percent of the time. But the human trainer was better – with a 100 percent accuracy rate.
However, while the average response time was about the same for both algorithm and trainer, there was a lot of variation in the time of response from the trainer. The algorithm was incredibly consistent.
“That variation matters, because consistency is fundamentally important for all animal training,” Roberts says.
“This study was a proof of concept, and demonstrates that this approach works,” Bozkurt says. “Next steps include teaching dogs to perform specific behaviors on cue, and integrating computer-assisted training and human-directed training for use in various service dog applications.”
“In the long term, we’re interested in using this approach to animal-computer interaction to allow dogs to ‘use’ computers,” Roberts says. “For example, allowing an explosive detection dog to safely and clearly mark when it detects components of a bomb, or allowing diabetic alert dogs to use their physical posture and behaviors to call for help.”
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Why the Most Tornadoes in May? Five Things You Need To Know About Tornadoes
May 30th, 2016By Alton Parrish.
In May when tornadoes are in the news, the National Science Foundation (NSF) spoke with tornado expert and NSF Assistant Director for Geosciences Roger Wakimoto to learn more about these deadly storms — including what new studies are telling us about how, where and when twisters form. The results will offer scientists better ways of predicting tornadoes.
1. Why does the U.S. seem to experience the most tornadoes in May?
The highest average number of U.S. tornadoes per month is in May, followed by June. May is the time when the two ingredients that are required — very unstable air and strong vertical wind shear — are most common. That being said, we’re now seeing a trend of tornadoes breaking out earlier in spring, such as April or even March
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2. What U.S. states/regions have the most tornadoes, and why?
The Great Plains is where the most tornadoes occur; the region is often referred to as Tornado Alley. It’s an ideal location due to warm, humid air flowing northward from the Gulf of Mexico at low levels, and cold, dry air coming down from Canada at upper levels, producing very unstable air. Beyond the Great Plains, tornadoes occurring over the southeastern U.S. have recently attracted scientists’ interest.
3. Are there tornadoes in countries other than the U.S.?
Tornadoes are typical in the mid-latitudes, between 30 and 50 degrees north and south. Countries that experience tornadoes include Bangladesh, Japan, Australia, New Zealand, China, South Africa, Argentina and many nations in Europe.
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4. What are we learning about how and when tornadoes form?
Tornadoes usually occur in association with particular types of severe storms, such as supercells and squall lines, called tornado parental storms. But not all these parental storms generate tornadoes. Tornadogenesis, as the formation of tornadoes is called, remains the “holy grail” of tornado research. Recent work suggests that the temperature of the outflow air from the parent thunderstorm could play a critical role. There is a lot we don’t yet understand, including the circumstances that produce tornado outbreaks.
A large wall cloud arcs around a rotating thunderstorm updraft. This storm was documented by the VORTEX2 field campaign on June 6, 2010 near Ogallala, Nebraska.
5. What will NSF-supported tornado research underway this spring tell us?
A field project called TWIRL (Tornadic Winds: In situ and Radar measurements at Low-levels) is now taking place. It will improve our understanding of tornadogenesis and tornado evolution. The research includes the use of three Doppler on Wheels (DOW) mobile radars, and vehicles with deployable pods for weather observations. Scientists Karen Kosiba and Josh Wurman of the Center for Severe Weather Research are conducting this follow-up study to the past NSF-funded VORTEX-2 field campaign.
NSF is also working with NOAA on a Congressionally-mandated project called VORTEX-SE, which focuses on studies of tornadoes that bring deadly threats to the southeastern U.S. NSF is supporting scientists from academic institutions, who are working with researchers at NOAA laboratories to conduct ongoing field research.
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Moon Orbiting the Dwarf Planet Makemake Discovered
May 30th, 2016By Alton Parrish.
Peering to the outskirts of our solar system, NASA’s Hubble Space Telescope has spotted a small, dark moon orbiting Makemake, the second brightest icy dwarf planet — after Pluto — in the Kuiper Belt.
The moon — provisionally designated S/2015 (136472) 1 and nicknamed MK 2 — is more than 1,300 times fainter than Makemake. MK 2 was seen approximately 13,000 miles from the dwarf planet, and its diameter is estimated to be 100 miles across. Makemake is 870 miles wide. The dwarf planet, discovered in 2005, is named for a creation deity of the Rapa Nui people of Easter Island.
Astronomers using the Hubble Space Telescope discovered a moon orbiting dwarf planet Makemake — the third largest known object past the orbit of Neptune, about two thirds the size of Pluto. Further observations of this moon may allow astronomers to calculate Makemake’s mass, which will give them a better idea of its density and thus its bulk composition. The Hubble Space Telescope has been instrumental in studying our outer solar system; it also discovered four of the five moons orbiting Pluto.
The Kuiper Belt is a vast reservoir of leftover frozen material from the construction of our solar system 4.5 billion years ago and home to several dwarf planets. Some of these worlds have known satellites, but this is the first discovery of a companion object to Makemake. Makemake is one of five dwarf planets recognized by the International Astronomical Union.
The observations were made in April 2015 with Hubble’s Wide Field Camera 3. Hubble’s unique ability to see faint objects near bright ones, together with its sharp resolution, allowed astronomers to pluck out the moon from Makemake’s glare. The discovery was announced today in a Minor Planet Electronic Circular.
This Hubble image reveals the first moon ever discovered around the dwarf planet Makemake. The tiny satellite, located just above Makemake in this image, is barely visible because it is almost lost in the glare of the very bright dwarf planet. Hubble’s sharp-eyed WFC3 made the observation in April 2015.
The observing team used the same Hubble technique to observe the moon as they did for finding the small satellites of Pluto in 2005, 2011, and 2012. Several previous searches around Makemake had turned up empty. “Our preliminary estimates show that the moon’s orbit seems to be edge-on, and that means that often when you look at the system you are going to miss the moon because it gets lost in the bright glare of Makemake,” said Alex Parker of Southwest Research Institute, Boulder, Colorado, who led the image analysis for the observations.
A moon’s discovery can provide valuable information on the dwarf-planet system. By measuring the moon’s orbit, astronomers can calculate a mass for the system and gain insight into its evolution.
Uncovering the moon also reinforces the idea that most dwarf planets have satellites.
“Makemake is in the class of rare Pluto-like objects, so finding a companion is important,” Parker said. “The discovery of this moon has given us an opportunity to study Makemake in far greater detail than we ever would have been able to without the companion.”
Finding this moon only increases the parallels between Pluto and Makemake. Both objects are already known to be covered in frozen methane. As was done with Pluto, further study of the satellite will easily reveal the density of Makemake, a key result that will indicate if the bulk compositions of Pluto and Makemake are also similar. “This new discovery opens a new chapter in comparative planetology in the outer solar system,” said team leader Marc Buie of the Southwest Research Institute, Boulder, Colorado.
The researchers will need more Hubble observations to make accurate measurements to determine if the moon’s orbit is elliptical or circular. Preliminary estimates indicate that if the moon is in a circular orbit, it completes a circuit around Makemake in 12 days or longer.
Determining the shape of the moon’s orbit will help settle the question of its origin. A tight circular orbit means that MK 2 is probably the product of a collision between Makemake and another Kuiper Belt Object. If the moon is in a wide, elongated orbit, it is more likely to be a captured object from the Kuiper Belt. Either event would have likely occurred several billion years ago, when the solar system was young.
The discovery may have solved one mystery about Makemake. Previous infrared studies of the dwarf planet revealed that while Makemake’s surface is almost entirely bright and very cold, some areas appear warmer than other areas. Astronomers had suggested that this discrepancy may be due to the sun warming discrete dark patches on Makemake’s surface. However, unless Makemake is in a special orientation, these dark patches should make the dwarf planet’s brightness vary substantially as it rotates. But this amount of variability has never been observed.
These previous infrared data did not have sufficient resolution to separate Makemake from MK 2. The team’s reanalysis, based on the new Hubble observations, suggests that much of the warmer surface detected previously in infrared light may, in reality, simply have been the dark surface of the companion MK 2.
This artist’s concept shows the distant dwarf planet Makemake and its newly discovered moon. Makemake and its moon, nicknamed MK 2, are more than 50 times farther away than Earth is from the sun.
There are several possibilities that could explain why the moon would have a charcoal-black surface, even though it is orbiting a dwarf planet that is as bright as fresh snow. One idea is that, unlike larger objects such as Makemake, MK 2 is small enough that it cannot gravitationally hold onto a bright, icy crust, which sublimates, changing from solid to gas, under sunlight. This would make the moon similar to comets and other Kuiper Belt Objects, many of which are covered with very dark material.
When Pluto’s moon Charon was discovered in 1978, astronomers quickly calculated the mass of the system. Pluto’s mass was hundreds of times smaller than the mass originally estimated when it was found in 1930. With Charon’s discovery, astronomers suddenly knew something was fundamentally different about Pluto. “That’s the kind of transformative measurement that having a satellite can enable,” Parker said.
The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C.
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From “Black Hole Seeds” Monster Black Holes Are Born
May 28th, 2016By Alton Parrish.
Using data from NASA’s Great Observatories, astronomers have found the best evidence yet for cosmic seeds in the early universe that should grow into supermassive black holes.
Researchers combined data from NASA’s Chandra X-ray Observatory, Hubble Space Telescope, and Spitzer Space Telescope to identify these possible black hole seeds. They discuss their findings in a paper that will appear in an upcoming issue of the Monthly Notices of the Royal Astronomical Society.
“Our discovery, if confirmed, explains how these monster black holes were born,” said Fabio Pacucci of Scuola Normale Superiore (SNS) in Pisa, Italy, who led the study. “We found evidence that supermassive black hole seeds can form directly from the collapse of a giant gas cloud, skipping any intermediate steps.”
Scientists believe a supermassive black hole lies in the center of nearly all large galaxies, including our own Milky Way. They have found that some of these supermassive black holes, which contain millions or even billions of times the mass of the sun, formed less than a billion years after the start of the universe in the Big Bang.
One theory suggests black hole seeds were built up by pulling in gas from their surroundings and by mergers of smaller black holes, a process that should take much longer than found for these quickly forming black holes.
These new findings suggest instead that some of the first black holes formed directly when a cloud of gas collapsed, bypassing any other intermediate phases, such as the formation and subsequent destruction of a massive star.
“There is a lot of controversy over which path these black holes take,” said co-author Andrea Ferrara, also of SNS. “Our work suggests we are narrowing in on an answer, where the black holes start big and grow at the normal rate, rather than starting small and growing at a very fast rate.”
The researchers used computer models of black hole seeds combined with a new method to select candidates for these objects from long-exposure images from Chandra, Hubble, and Spitzer.
The team found two strong candidates for black hole seeds. Both of these matched the theoretical profile in the infrared data, including being very red objects, and also emit X-rays detected with Chandra. Estimates of their distance suggest they may have been formed when the universe was less than a billion years old
This computer-simulated image shows a supermassive black hole at the core of a galaxy. The black region in the center represents the black hole’s event horizon, where no light can escape the massive object’s gravitational grip. The black hole’s powerful gravity distorts space around it like a funhouse mirror. Light from background stars is stretched and smeared as the stars skim by the black hole.
“Black hole seeds are extremely hard to find and confirming their detection is very difficult,” said Andrea Grazian, a co-author from the National Institute for Astrophysics in Italy. “However, we think our research has uncovered the two best candidates to date.”
The team plans to obtain further observations in X-rays and the infrared to check whether these objects have more of the properties expected for black hole seeds. Upcoming observatories, such as NASA’s James Webb Space Telescope and the European Extremely Large Telescope will aid in future studies by detecting the light from more distant and smaller black holes. Scientists currently are building the theoretical framework needed to interpret the upcoming data, with the aim of finding the first black holes in the universe.
“As scientists, we cannot say at this point that our model is ‘the one’,” said Pacucci. “What we really believe is that our model is able to reproduce the observations without requiring unreasonable assumptions.”
NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program while the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra’s science and flight operations.
The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington.
NASA’s Jet Propulsion Laboratory in Pasadena, California, manages the Spitzer Space Telescope mission, whose science operations are conducted at the Spitzer Science Center. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado.
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Ancient DNA Study Finds Phoenician from Carthage Had European Ancestry
May 28th, 2016By Alton Parrish.
A research team co-led by a scientist at New Zealand’s University of Otago has sequenced the first complete mitochondrial genome of a 2500-year-old Phoenician dubbed the “Young Man of Byrsa” or “Ariche”.
This is the first ancient DNA to be obtained from Phoenician remains and the team’s analysis shows that the man belonged to a rare European haplogroup — a genetic group with a common ancestor — that likely links his maternal ancestry to locations somewhere on the North Mediterranean coast, most probably on the Iberian Peninsula.
A research team co-led by a scientist at New Zealand’s University of Otago has sequenced the first complete mitochondrial genome of a 2500-year-old Phoenician dubbed the “Young Man of Byrsa” or “Ariche”. This is the first ancient DNA to be obtained from Phoenician remains. Ariche was found to have belonged to a rare European haplogroup that likely links his maternal ancestry to locations somewhere on the North Mediterranean coast, most probably on the Iberian Peninsula.
The findings are newly published in the prestigious international journal PLOS ONE.
Study co-leader Professor Lisa Matisoo-Smith of the Department of Anatomy says the findings provide the earliest evidence of the European mitochondrial haplogroup U5b2c1 in North Africa and date its arrival to at least the late sixth century BC.
“U5b2c1 is considered to be one of the most ancient haplogroups in Europe and is associated with hunter-gatherer populations there. It is remarkably rare in modern populations today, found in Europe at levels of less than one per cent. Interestingly, our analysis showed that Ariche’s mitochondrial genetic make-up most closely matches that of the sequence of a particular modern day individual from Portugal,” Professor Matisoo-Smith says.
While the Phoenicians are thought to have originated from the area that is now Lebanon, their influence expanded across the Mediterranean and west to the Iberian Peninsula where they established settlements and trading posts. The city of Carthage in Tunisia, North Africa, was established as a Phoenician port by colonists from Lebanon and became the centre for later Phoenician (Punic) trade.
The researchers analysed the mitochondrial DNA of 47 modern Lebanese people and found none were of the U5b2c1 lineage.
Previous research has found that U5b2c1 was present in two ancient hunter-gatherers recovered from an archaeological site in north-western Spain, she says.
“While a wave of farming peoples from the Near East replaced these hunter-gatherers, some of their lineages may have persisted longer in the far south of the Iberian peninsula and on off-shore islands and were then transported to the melting pot of Carthage in North Africa via Phoenician and Punic trade networks.”
Professor Matisoo-Smith says Phoenician culture and trade had a significant impact on Western civilisation. For example, they introduced the first alphabetic writing system.
“However, we still know little about the Phoenicians themselves, except for the likely biased accounts by their Roman and Greek rivals — hopefully our findings and other continuing research will cast further light on the origins and impact of Phoenician peoples and their culture,” she says
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Supermassive Black Holes in ‘Red Geyser’ Galaxies Cause Galactic Warming
May 27th, 2016By Alton Parrish.
An international team of scientists, including the University of Kentucky’s Renbin Yan, have uncovered a new class of galaxies, called “red geysers,” with supermassive black hole winds so hot and energetic that stars can’t form.
Over the last few billion years, a mysterious kind of “galactic warming” has caused many galaxies to change from a lively place where new stars formed every now and then to a quiet place devoid of fresh young stars. But the mechanism that produces this dramatic transformation and keeps galaxies quiet has been one of the biggest unsolved mysteries in galaxy evolution.
“These galaxies have the necessary ingredients for forming new stars but they are not doing it – why?” said Yan, an assistant professor of physics and astronomy at UK.
Researchers compare it to having deserts in densely clouded regions; rain and vegetation would be expected, not a barren landscape. Yan and astronomers from the Sloan Digital Sky Survey (SDSS) are solving the mystery in a study published today in Nature, announcing the discovery of the red geysers.
Red geysers are old galaxies hosting low-energy supermassive black holes which drive intense interstellar winds. These winds suppress star formation by heating up the ambient gas found in galaxies and preventing it from cooling and condensing into stars.
Yan, also the survey scientist for the survey called Mapping Nearby Galaxies at Apache Point Observatory (MaNGA), was working with the international team, including lead author Edmond Cheung of the University of Tokyo, to study hundreds of galaxies when they caught a supermassive black hole blasting away at the cold gas in its host galaxy.
“With MaNGA’s technological upgrade to the Sloan Foundation Telescope, we can make detailed maps of galaxies ten to a hundred times faster than we could just ten years ago,” Yan said.
Yan and his team at MaNGA are mapping the details of 10,000 nearby galaxies – the largest survey yet of its kind – with the goal to understand the galaxies’ life cycles. Unlike previous SDSS surveys, they are not only mapping the centers of galaxies where supermassive black holes live, but the outer edges of the galaxies as well, which allowed them to discover the red geyser galaxy.
The winds powered by these supermassive black holes could come and go quickly. It is difficult to catch the moment they show up. “Since MaNGA studies so many galaxies, our snapshots can reveal even the quickest changes to galaxies,” Yan said. “And that’s how we found Akira.”
“Akira,” an example of a red geyser galaxy nicknamed by Cheung, has a companion galaxy that called “Tetsuo.” Akira is pulling gas away from Tetsuo, which fuels Akira’s supermassive black hole. The winds driven by the black hole are the reason that Akira is currently a red geyser galaxy.
Kevin Bundy, MaNGA principal investigator, came up with the name “red geyser” because these wind outbursts reminded him of the sporadic eruptions of a geyser and because failure to form new stars left the galaxy with only red stars.
As with global warming on Earth, galactic warming has long-term consequences for red geyser galaxies – their gas can no longer form new stars.
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Huge Coronal Hole Opens on the Sun
May 27th, 2016
By Alton Parrish.
This imagery of the sun captured by NASA’s Solar Dynamics Observatory from May 17-19, 2016, shows a giant dark area on the star’s upper half, known as a coronal hole. Coronal holes are low-density regions of the sun’s atmosphere, known as the corona. Because they contain little solar material, they have lower temperatures and thus appear much darker than their surroundings. Coronal holes are visible in certain types of extreme ultraviolet light, which is typically invisible to our eyes, but is colorized here in purple for easy viewing
These coronal holes are important to understanding the space environment around Earth through which our technology and astronauts travel. Coronal holes are the source of a high-speed wind of solar particles that streams off the sun some three times faster than the slower wind elsewhere. While it’s unclear what causes coronal holes, they correlate to areas on the sun where magnetic fields soar up and away, without looping back down to the surface, as they do elsewhere.
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Tycho Supernova Explosion 15 Years Condensed into Seconds: Chandra Movie Captures Expanding Debris from a Star’s Demise
May 26th, 2016By Alton Parrish.
An explosion too big for even Hollywood. A spectacle hundreds of years in the making.
When the star that created this supernova remnant exploded in 1572, it was so bright that it was visible during the day. And though he wasn’t the first or only person to observe this stellar spectacle, the Danish astronomer Tycho Brahe wrote a book about his extensive observations of the event, gaining the honor of it being named after him.
In modern times, astronomers have observed the debris field from this explosion − what is now known as Tycho’s supernova remnant − using data from NASA’s Chandra X-ray Observatory, the NSF’s Karl G. Jansky Very Large Array (VLA) and many other telescopes. Today, they know that the Tycho remnant was created by the explosion of a white dwarf star, making it part of the so-called Type Ia class of supernovas used to track the expansion of the Universe.
Since much of the material being flung out from the shattered star has been heated by shock waves − similar to sonic booms from supersonic planes − passing through it, the remnant glows strongly in X-ray light. Astronomers have now used Chandra observations from 2000 through 2015 to create the longest movie of the Tycho remnant’s X-ray evolution over time, using five different images. This shows the expansion from the explosion is still continuing about 450 years later, as seen from Earth’s vantage point roughly 10,000 light years away.
By combining the X-ray data with some 30 years of observations in radio waves with the VLA, astronomers have also produced a movie, using three different images. Astronomers have used these X-ray and radio data to learn new things about this supernova and its remnant.
This image comes from a very deep Chandra observation of the Tycho supernova remnant, produced by the explosion of a white dwarf star in our Galaxy. Low-energy X-rays (red) in the image show expanding debris from the supernova explosion and high energy X-rays (blue) show the blast wave, a shell of extremely energetic electrons
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The researchers measured the speed of the blast wave at many different locations around the remnant. The large size of the remnant enables this motion to be measured with relatively high precision. Although the remnant is approximately circular, there are clear differences in the speed of the blast wave in different regions. The speed in the right and lower right directions is about twice as large as that in the left and the upper left directions. This difference was also seen in earlier observations.
This range in speed of the blast wave’s outward motion is caused by differences in the density of gas surrounding the supernova remnant. This causes an offset in position of the explosion site from the geometric center, determined by locating the center of the circular remnant. The astronomers found that the size of the offset is about 10% of the remnant’s current radius, towards the upper left of the geometric center. The team also found that the maximum speed of the blast wave is about 12 million miles per hour.
Offsets such as this between the explosion center and the geometric center could exist in other supernova remnants. Understanding the location of the explosion center for Type Ia supernovas is important because it narrows the search region for a surviving companion star. Any surviving companion star would help identify the trigger mechanism for the supernova, showing that the white dwarf pulled material from the companion star until it reached a critical mass and exploded. The lack of a companion star would favor the other main trigger mechanism, where two white dwarfs merge causing the critical mass to be exceeded, leaving no star behind
The significant offset from the center of the explosion to the remnant’s geometric center is a relatively recent phenomenon. For the first few hundred years of the remnant, the explosion’s shock was so powerful that the density of gas it was running into did not affect its motion. The density discrepancy from the left side to the right has increased as the shock moved outwards, causing the offset in position between the explosion center and the geometric center to grow with time. So, if future X-ray astronomers, say 1,000 years from now, do the same observation, they should find a much larger offset.
A paper describing these results has been accepted for publication in The Astrophysical Journal Letters and is available online. The authors are Brian Williams (NASA’s Goddard Space Flight Center and Universities Space Research Association), Laura Chomiuk (Michigan State University), John Hewitt (University of North Florida), John Blondin (North Carolina State University), Kazimierz Borkowski (NCSU), Parviz Ghavamian (Towson University), Robert Petre (GSFC), and Stephen Reynolds (NCSU).
NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra’s science and flight operations.
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Pluto’s Venera Terra, Utterly Alien Landscape, Unlike Anything Ever Seen
May 26th, 2016By Alton Parrish.
In looking over images of Pluto’s informally named Venera Terra region, New Horizons scientists have spotted an expanse of terrain they describe as “fretted.” As shown in the enhanced-color image at top, this terrain consists of bright plains divided into polygon-shaped blocks by a network of dark, connected valleys typically reaching a few miles (3 to 4 kilometers) wide. Numerous impact craters of up to 15 miles (25 kilometers) in diameter also dot the area, implying the surface formed early in Pluto’s history.
New Horizons scientists haven’t seen this type of terrain anywhere else on Pluto; in fact, it’s rare terrain across the solar system – the only other well-known example of such being Noctis Labyrinthus on Mars. The distinct interconnected valley network was likely formed by extensional fracturing of Pluto’s surface.
The valleys separating the blocks may then have been widened by movement of nitrogen ice glaciers, or flowing liquids, or possibly by ice sublimation at the block margins. Compositional data from New Horizons’ Ralph/Multispectral Visible Imaging Camera (MVIC), shown in the bottom image, indicate that the blocks are rich in methane ice (shown as false-color purple); methane is susceptible to sublimation at Pluto surface conditions.
The resolution of these MVIC images is approximately 2,230 feet (680 meters) per pixel. They were obtained at a range of approximately 21,100 miles (33,900 kilometers) from Pluto, about 45 minutes before New Horizons’ closest approach on July 14, 2015.
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This newest shaded relief view of the region surrounding the left side of Pluto’s heart-shaped feature – informally named Sputnik Planum – shows that the vast expanse of the icy surface is on average 2 miles (3 kilometers) lower than the surrounding terrain. Angular blocks of water ice along the western edge of Sputnik Planum can be seen “floating” in the bright deposits of softer, denser solid nitrogen.
Topographic maps of Pluto are produced from digital analysis of New Horizons stereo images acquired during the July 14, 2015 flyby. Such maps are derived from digital stereo-image mapping tools that measure the parallax – or the difference in the apparent relative positions – of individual features on the surface obtained at different times. Parallax displacements of high and low features are then used to directly estimate feature heights.
These topographic maps are works in progress and artifacts are still present in the current version. The map is artificially illuminated from the south, rather than the generally northern solar lighting of landscape during the time of the flyby. One of the many advantages of digital terrain maps is that they can be illuminated from any direction to best bring out different features. North is up and the total relief in the scene is approximately 4 miles (6 kilometers) from the lowest to the highest features.
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Flying RoboBees, Tiny Surveillance Helicopters and Swarms of Smart Gliders
May 25th, 2016By Alton Parrish.
Flying micro-robots have a fine future carrying out almost every imaginable task in surveillance and detection. You can run but it is getting harder and harder to hide.
In a recent article in Science, Harvard roboticists demonstrated that their flying microrobots, nicknamed the RoboBees, can now perch during flight to save energy – like bats, birds or butterflies.
“Many applications for small drones require them to stay in the air for extended periods,” said Moritz Graule, first author of the paper who conducted this research as a student at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) and Wyss Institute for Biologically Inspired Engineering at Harvard University. “Unfortunately, smaller drones run out of energy quickly. We want to keep them aloft longer without requiring too much additional energy.”
The team found inspiration in nature and simple science.
“A lot of different animals use perching to conserve energy,” said Kevin Ma, a post-doc at SEAS and the Wyss Institute and coauthor. “But the methods they use to perch, like sticky adhesives or latching with talons, are inappropriate for a paperclip-size microrobot, as they either require intricate systems with moving parts or high forces for detachment.”
Instead, the team turned to electrostatic adhesion — the same basic science that causes a static-charged sock to cling to a pants leg or a balloon to stick to a wall.
When you rub a balloon on a wool sweater, the balloon becomes negatively charged. If the charged balloon is brought close to a wall, that negative charge forces some of the wall’s electrons away, leaving the surface positively charged. The attraction between opposite charges then causes the balloon to stick to the wall.
“In the case of the balloon, however, the charges dissipate over time, and the balloon will eventually fall down,” said Graule. “In our system, a small amount of energy is constantly supplied to maintain the attraction.”
The RoboBee, pioneered at the Harvard Microrobotics Lab, uses an electrode patch and a foam mount that absorbs shock. The entire mechanism weighs 13.4 mg, bringing the total weight of the robot to about 100mg — similar to the weight of a real bee. The robot takes off and flies normally. When the electrode patch is supplied with a charge, it can stick to almost any surface, from glass to wood to a leaf. To detach, the power supply is simply switched off.
“One of the biggest advantages of this system is that it doesn’t cause destabilizing forces during disengagement, which is crucial for a robot as small and delicate as ours,” said Graule.
The patch requires about 1000 times less power to perch than it does to hover, offering to dramatically extend the operational life of the robot. Reducing the robot’s power requirements is critical for the researchers, as they work to integrate onboard batteries on untethered RoboBees.
“The use of adhesives that are controllable without complex physical mechanisms, are low power, and can adhere to a large array of surfaces is perfect for robots that are agile yet have limited payload – like the RoboBee,” added Robert Wood, Charles River Professor of Engineering and Applied Sciences at SEAS, a core faculty member of the Wyss Institute, and senior author of the study. “When making robots the size of insects, simplicity and low power are always key constraints.”
Right now, the RoboBee can only perch under overhangs and on ceilings, as the electrostatic patch is attached to the top of the vehicle. Next, the team hopes to change the mechanical design so that the robot can perch on any surface.
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“There are more challenges to making a robust, robotic landing system but this experimental result demonstrates a very versatile solution to the problem of keeping flying microrobots operating longer without quickly draining power,” said Ma.
The paper was coauthored by Pakpong Chirarattananon, Sawyer B. Fuller, Noah Jafferis, Matthew Spenko and Roy Kornbluh. The research was funded by the National Science Foundation, the Wyss Institute for Biologically Inspired Engineering, and the Swiss Study Foundation.
Flying micro-drones are of great interest to the military. Prox Dynamics is selling a micro-drone designed to give a squad of Marines their own tiny surveillance capability. The PD-100 Black Hornet weighs 18 grams and its body is around the size of a hummingbird. It comes in a day version that snags full-motion video and a night version that can capture thermal images.
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The unit measures around 10 × 2.5 cm (4 × 1 in) and provides troops on the ground with local situational awareness. They are small enough to fit in one hand and weigh just over half an ounce (16 g, including batteries).
The UAV is equipped with a camera, which gives the operator full-motion video and still images. They were developed as part of a £20 million contract for 160 units with Marlborough Communications Ltd.
The Marine Corps Warfighting Laboratory is interested in the PD-100 Black Hornet, a small unmanned aircraft that can capture full-motion video and thermal images in real time.
The Marine Corps Warfighting Laboratory’s Unmanned Tactical Autonomous Control and Collaboration (UTACC) leverages advanced robotics and autonomy to minimize operator workload – putting the Marine back into the fight. UTACC is a team of autonomous air and ground robots that provides multi-dimensional ISR to the squad level of operations.
The end state of the UTACC is to enhance infantry squad missions accomplishment while simultaneously reducing the cognitive load on the operator. The Marine Corps Warfighting Laboratory is conducting the second Limited Technical Assessment on the UTACC later this month as part of its continued exploration of Manned Unmanned Teaming (MUMT).
The Marine Corps Warfighting Laboratory is also evaluating the Modular Advanced Armed Robotic System, a tracked vehicle with several sensors and armed with a M240B machine gun.
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The U.S. Naval Laboratory is developing CICADA, a concept for a low-cost, GPS-guided, micro disposable air vehicle that can be deployed in large numbers to “seed” an area with miniature electronic payloads. These payloads could be interconnected to form an ad-hoc, self-configuring network. Communication nodes, sensors, or effectors can then be placed in a programmable geometric pattern in hostile territory without directly over-flying those regions or exposing human agents on the ground.
Essentially a flying circuit board, CICADA has an extremely high packing factor and a very low per-unit cost. Eighteen vehicles can be contained in a six-inch cube. The vehicle is inherently stable in glide, with a glide ratio of 3.5.
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Other Worldly Philately: New Stamps Honoring NASA Planetary Discoveries Debut May 31
May 25th, 2016
By Alton Parrish.
With this pane of 16 Forever stamps, the Postal Service showcases some of the more visually compelling historic, full-disk images of the planets obtained during the last half-century of NASA space exploration. Eight new colorful Forever stamps – each shown twice – feature Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
Coming next week to a post office near you: new “Views of Our Planets” Forever stamps featuring iconic images of the planets in our solar system, including the well-known “Blue Marble” photo of Earth. New “Pluto Explored” Forever stamps commemorating the July 2015 flyby of Pluto by NASA’s New Horizons spacecraft also are being issued for online purchase.
The May 31 first-day-of-issue dedication ceremony for the Pluto and planetary stamps will be in New York City at World Stamp Show-NY 2016. This international gathering of stamp collectors occurs only once each decade in the United States, and – with more than 250,000 visitors expected to attend – is the largest stamp show in the world.
“The unveiling of these breathtaking new images of Pluto and our planets will be an exciting day for NASA and for all who love space exploration, said Jim Green, director of planetary science at NASA Headquarters in Washington. “With the 2015 Pluto flyby, we’ve completed the initial reconnaissance of the solar system, and we’re grateful to the U.S. Postal Service for commemorating this historic achievement.”
Green will be among featured speakers and honored guests at an 11 a.m. EDT ceremony at the Jacob Javits Convention Center in New York. Among other VIPs scheduled to attend are: Dave Williams, chief operating officer and executive vice president of the U.S. Postal Service; NASA Chief Scientist Ellen Stofan; John Grunsfeld, astronaut and former associate administrator for NASA’s Science Mission Directorate; New Horizons Principal Investigator Alan Stern, Southwest Research Institute; New Horizons Mission Operations Manager Alice Bowman, Johns Hopkins University Applied Physics Laboratory (APL); and Norman Kuring, oceanographer at NASA’s Goddard Space Flight Center.
The souvenir sheet of four New Horizons stamps features two new stamps appearing twice. The first stamp is an artist’s rendering of NASA’s New Horizons spacecraft based on artwork created by APL’s Steve Gribben, while the second stamp shows an enhanced color image of Pluto taken by New Horizons near its closest approach to Pluto.
The Pluto stamps are of special significance to NASA and the New Horizons team, which placed a 29-cent 1991 “Pluto: Not Yet Explored” stamp on board the APL-built spacecraft. On July 14, 2015, New Horizons carried the stamp on its history-making journey to Pluto and beyond, as jubilant members of the mission team celebrated with a large print, striking the words “not yet.”
Pluto Explored. (left to right): New Horizons Principal Investigator Alan Stern of Southwest Research Institute (SwRI), Boulder, Colorado; New Horizons’ Deputy Project Scientist Leslie Young, SwRI; APL Director Ralph Semmel; Annette Tombaugh, daughter of Clyde Tombaugh, who discovered Pluto in 1930; and New Horizons Co-Investigator Will Grundy, Lowell Observatory, Flagstaff, Arizona, hold a print of the 1991 Pluto stamp – with their suggested update – on July 14, 2015 at APL in Laurel, Maryland.
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“The 1991 stamp that showed Pluto ‘not yet explored’ highlighted some important, unfinished business for NASA’s first exploration of the planets of our solar system,” said Stern. “I’m thrilled that 25 years later, these new stamps recognize that Pluto has, indeed, been explored by the New Horizons spacecraft and has been revealed to be a complex and fascinating world.”
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Meet the New Ocean Overlords
May 24th, 2016By Alton Parrish.
Big things are happening in the oceans. The seas may see a new status quo.
Humans have changed the world’s oceans in ways that have been devastating to many marine species. But, according to new evidence, it appears that the change has so far been good for cephalopods, the group including octopuses, cuttlefish, and squid. The study reported in the Cell Press journal Current Biology on May 23 shows that cephalopods’ numbers have increased significantly over the last six decades.
“The consistency was the biggest surprise,” says Zoë Doubleday of Australia’s Environment Institute at the University of Adelaide. “Cephalopods are notoriously variable, and population abundance can fluctuate wildly, both within and among species. The fact that we observed consistent, long-term increases in three diverse groups of cephalopods, which inhabit everything from rock pools to open oceans, is remarkable.”
According to the researchers, there has been growing speculation that cephalopod populations were proliferating in response to a changing environment, based partly on trends in cephalopod fisheries. Cephalopods are known for rapid growth, short lifespans, and extra-sensitive physiologies, which may allow them to adapt more quickly than many other marine species.
To investigate long-term trends in cephalopod abundance, Doubleday and her colleagues assembled global time series of cephalopod catch rates (catch per unit of fishing or sampling effort) from 1953 to 2013. The study included 35 cephalopod species or genera representing six families. The data show that cephalopods, of many different types living all over the world, are on the rise.
The ecological and socio-economic ramifications associated with this increase in cephalopods are much less clear and are likely to be complex, according to the researchers.
“Cephalopods are voracious and adaptable predators and increased predation by cephalopods could impact many prey species, including commercially valuable fish and invertebrates,” they write. “Conversely, increases in cephalopod populations could benefit marine predators which are reliant on them for food, as well as human communities reliant on them as a fisheries resource.”
What may happen to cephalopod populations in the future is difficult to predict, particularly if fishing pressure continues to increase. Doubleday says that they are now investigating the factors responsible for cephalopods’ proliferation.
“It is a difficult, but important, question to answer, as it may tell us an even bigger story about how human activities are changing the ocean,” she says.
The research, funded by the Environment Institute at the University of Adelaide, was the result of a workshop involving researchers all over the world
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East Antarctic Glacier Contributed To Several Sea Level Rises In The Past
May 24th, 2016By Alton parrish.
Research published in the journal Nature on May 19 has revealed that vast regions of the Totten Glacier in East Antarctica are fundamentally unstable and have contributed significantly to rising sea levels several times in the past.
Totten Glacier is the most rapidly thinning glacier in East Antarctica, and this study raises concerns that a repeat transition between stable and unstable states could be underway as the climate warms.
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Totten Glacier’s ice shelf.
An international consortium led by The University of Texas at Austin’s Institute for Geophysics (UTIG), a unit at the university’s Jackson School of Geosciences, led the research and data collection for the study. Alan Aitken of the University of Western Australia’s School of Earth and Environment is the lead author.
Totten Glacier is East Antarctica’s largest outlet of ice and a key region for understanding the large-scale and long-term vulnerabilities of the Antarctic Ice Sheet. Until now, knowledge of the region’s glacial history has been very limited. Whereas other studies have indicated that this region of the ice sheet may have retreated in the past, this study reveals direct linkages between the modern Totten Glacier and the eroded landscape currently buried in ice hundreds of kilometers inland.
“We now know how the ice sheet evolves over the landscape in East Antarctica and where it is susceptible to rapid retreat, which gives us insight into what is likely to happen in the years ahead,” said Donald D. Blankenship, lead principal investigator of ICECAP (International Collaboration for Exploration of the Cryosphere through Aerogeophysical Profiling) and a senior research scientist at UTIG.
Totten Glacier’s catchment is a collection basin for ice and snow that flows through the glacier.
“Totten Glacier’s catchment is covered by nearly 2½ miles of ice, filling a California-sized sub-ice basin that reaches depths of over one mile below sea level,” Blankenship said. “This study shows that this system could have a large impact on sea level in a short period of time.”
The UTIG-led ICECAP project collected the data during five Antarctic field campaigns using an aircraft equipped with instruments to assess the ice and measure the shape of the landscape and rocks beneath it. The airplane was outfitted with radar that can measure ice several miles thick, lasers to measure the shape and elevation of the ice surface, and equipment that senses Earth’s gravity and magnetic field strengths, which are used to infer the sub-ice geology.
The study used ice-penetrating radar, magnetic and gravity data to determine the thickness of the ice sheet and the sediment thickness under the ice sheet. These were used to map glacial erosion beneath the ice and find two unstable zones where the ice sheet is prone to rapid collapse.
“By examining the characteristic patterns of erosion left by past ice sheet advance and retreat, revealed through mapping the topographic surface and the thickness of sedimentary rocks beneath, this paper demonstrates direct evidence of past changes in the ice sheet in the Totten region,” Aitken said.
The study found the transition between the stable and unstable states has occurred repeatedly during the life of the ice sheet.
“If this was to happen again, with a warmer climate than today, it could lead to a rapid rise in sea level of over a meter,” Aitken said.
ICECAP is a long-term international collaboration among the United States, Australia, the United Kingdom and France. The data for this study were gathered with the support of the U.K.’s Natural Environment Research Council, the U.S. National Science Foundation and the Australian Antarctic Division, as well as NASA’s Operation IceBridge, the G. Unger Vetlesen Foundation, and UT Austin’s Jackson School of Geosciences. The ICECAP aircraft was operated under contract to UTIG by Kenn Borek Air Ltd., Calgary, Alberta, Canada
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Flora Keeps the Mind Sharp — With Some Help from the Immune System
May 23rd, 2016By Alton Parrish.
A special kind of immune cell serves as an intermediary between gut bacteria and the brain. Dr. Susanne Wolf of the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC) discovered this in tests on mice and published her findings in the journal Cell Reports. The research findings are of significance when it comes to the effects of using antibiotics in the long term, and could also help to alleviate the symptoms of mental disorders.
The gut and the brain “talk” to one another via hormones, metabolic products or direct neural connections. A specific population of monocyte immune cells acts as a further link between the two, as Dr. Susanne Wolf from the MDC research group led by Prof. Helmut Kettenmann recently discovered in collaboration with colleagues from the University of Magdeburg, the Charité – Universitätsmedizin Berlin, and the US National Institutes of Health (NIH).
This is the hippocampus after treatment with antibiotics: only few new cells are visible (marked red).
The researchers switched off the gut microbiome in mice, i.e. their intestinal bacteria, with a strong concoction of antibiotics. Compared to the mice that had not undergone treatment, they subsequently observed significantly fewer newly formed nerve cells in the hippocampus region of the brain. The memory of the treated mice also deteriorated because the formation of these new brain cells – a process known as neurogenesis – is important for certain memory functions.
As well as impaired neurogenesis, the researchers also found that the population of a specific immune cell in the brain – the Ly6C(hi) monocytes – decreased significantly when the microbiota was switched off. Could these immune cells be a previously unknown intermediary between the two organ systems? Wolf and her team tested and confirmed this hypothesis: when they removed just these cells from the mice, neurogenesis declined and when they gave the cells to the mice that had been on antibiotics, neurogenesis increased once again.
The researchers cured the antibiotic-treated mice using two different strategies: the mice were either given a mixture of selected bacterial strains or had access to voluntary training in the running wheel, thus reversing the negative effects of the antibiotics. The mice’s number of monocytes increased and their memory performance and neurogenesis improved. However, it was not possible to restore the immune and brain functions using the microbiota of untreated mice.
According to Wolf, the previously unknown intermediary function of the immune cells is of particular scientific interest: “With the Ly6C(hi) monocytes, we may have discovered a new general communication path from the periphery to the brain.”
Applied to humans, the findings do not show that all antibiotics disrupt brain function, as the combination of drugs used in the study was extremely potent. “It is possible, however, that similar effects could result from treatments involving long-term use of antibiotics,” says Wolf. The research team also found that the antibiotics may affect neurogenesis directly, and not act only via the gut bacteria.
According to Wolf, the new study is also of significance for treating people with mental disorders such as schizophrenia or depression, who also have impaired neurogenesis: “In addition to medication and physical exercise, these patients could potentially also benefit from probiotic preparations. In order to test this, we would like to conduct clinical pilot studies together with the Charité.”
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Engineers Take First Step Toward Flexible, Wearable, Tricorder-Like Device
May 23rd, 2016
By Alton Parrish.
Engineers at the University of California San Diego have developed the first flexible wearable device capable of monitoring both biochemical and electric signals in the human body. The Chem-Phys patch records electrocardiogram (EKG) heart signals and tracks levels of lactate, a biochemical that is a marker of physical effort, in real time. The device can be worn on the chest and communicates wirelessly with a smartphone, smart watch or laptop. It could have a wide range of applications, from athletes monitoring their workouts to physicians monitoring patients with heart disease.
The ChemPhys patch can be worn on the chest, near the base of the sternum, and communicates wirelessly with a smartphone, smart watch or laptop.
Nanoengineers and electrical engineers at the UC San Diego Center for Wearable Sensors worked together to build the device, which includes a flexible suite of sensors and a small electronic board. The device also can transmit the data from biochemical and electrical signals via Bluetooth.
Nanoengineering professor Joseph Wang and electrical engineering professor Patrick Mercier at the UC San Diego Jacobs School of Engineering led the project, with Wang’s team working on the patch’s sensors and chemistry, while Mercier’s team worked on the electronics and data transmission. They describe the Chem-Phys patch in the May 23 issue of Nature Communications.
“One of the overarching goals of our research is to build a wearable tricorder-like device that can measure simultaneously a whole suite of chemical, physical and electrophysiological signals continuously throughout the day,” Mercier said. “This research represents an important first step to show this may be possible.”
Most commercial wearables only measure one signal, such as steps or heart rate, Mercier said. Almost none of them measure chemical signals, such as lactate.
That is the gap that the sensor designed by researchers at the Jacobs School of Engineering at UC San Diego aims to bridge. Combining information about heart rate and lactate–a first in the field of wearable sensors–could be especially useful for athletes wanting to improve their performance. Both Mercier and Wang have been fielding inquiries from Olympic athletes about the technologies the Center for Wearable Sensors produces.
“The ability to sense both EKG and lactate in a small wearable sensor could provide benefits in a variety of areas,” explained Dr. Kevin Patrick, a physician and director of the Center for Wireless and Population Health Systems at UC San Diego, who was not involved with the research. “There would certainly be interest in the sports medicine community about how this type of sensing could help optimize training regimens for elite athletes,” added Patrick, who is also a member of the Center for Wearable Sensors. “The ability to concurrently assess EKG and lactate could also open up some interesting possibilities in preventing and/or managing individuals with cardiovascular disease.”
The researchers’ biggest challenge was making sure that signals from the two sensors didn’t interfere with each other. This required some careful engineering and a fair bit of experimentation before finding the right configuration for the sensors.
Making the patch
Researchers used screen printing to manufacture the patch on a thin, flexible polyester sheet that can be applied directly to the skin. An electrode to sense lactate was printed in the center of the patch, with two EKG electrodes bracketing it to the left and the right. Engineers went through several iterations of the patch to find the best distance between electrodes to avoid interference while gathering the best quality signal. They found that a distance of four centimeters (roughly 1.5 inches) between the EKG electrodes was optimal.
Study co-author Amay Bandodkar wears the ChemPhys patch while using an exercise bike in a lab at the Center for Wearable Sensors.
Researchers also had to make sure the EKG sensors were isolated from the lactate sensor. The latter works by applying a small voltage and measuring electric current across its electrodes. This current can pass through sweat, which is slightly conductive, and can potentially disrupt EKG measurements. So the researchers added a printed layer of soft water-repelling silicone rubber to the patch and configured it to keep the sweat away from the EKG electrodes, but not the lactate sensor.
The sensors were then connected to a small custom printed circuit board equipped with a microcontroller and a Bluetooth Low Energy chip, which wirelessly transmitted the data gathered by the patch to a smartphone or a computer.
Testing
The patch was tested on three male subjects, who wore the device on their chest, near the base of their sternum, while doing 15 to 30 minutes of intense activity on a stationary bike. Two of the subjects also wore a commercial wristband heart rate monitor. The data collected by the EKG electrodes on the patch closely matched the data collected by the commercial wristband. The data collected by the lactate biosensor follows closely data collected during increasing intensity workouts in other studies.
Next steps
Next steps include improving the way the patch and the board are connected and adding sensors for other chemical markers, such as magnesium and potassium, as well as other vital signs. Physicians working with Wang and Mercier are also excited about the possibility of analyzing the data from the two signals and see how they correlate.
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Van Allen Probes Reveal Long-term Behavior of Earth’s Ring Current
May 21st, 2016By Alton Parrish.
New findings based on a year’s worth of observations from NASA’s Van Allen Probes have revealed that the ring current – an electrical current carried by energetic ions that encircles our planet – behaves in a much different way than previously understood.
The ring current has long been thought to wax and wane over time, but the new observations show that this is true of only some of the particles, while other particles are present consistently. Using data gathered by the Radiation Belt Storm Probes Ion Composition Experiment, or RBSPICE, on one of the Van Allen Probes, researchers have determined that the high-energy protons in the ring current change in a completely different way from the current’s low-energy protons. Such information can help adjust our understanding and models of the ring current – which is a key part of the space environment around Earth that can affect our satellites.
The findings were published in Geophysical Research Letters.
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“We study the ring current because, for one thing, it drives a global system of electrical currents both in space and on Earth’s surface, which during intense geomagnetic storms can cause severe damages to our technological systems,” said lead author of the study Matina Gkioulidou, a space physicist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland. “It also modifies the magnetic field in near-Earth space, which in turn controls the motion of the radiation belt particles that surround our planet. That means that understanding the dynamics of the ring current really matters in helping us understand how radiation belts evolve as well.”
The ring current lies at a distance of approximately 6,200 to 37,000 miles (10,000 to 60,000 km) from Earth. The ring current was hypothesized in the early 20th century to explain observed global decreases in the Earth’s surface magnetic field, which can be measured by ground magnetometers. Such changes of the ground magnetic field are described by what’s called the Sym-H index.
“Previously, the state of the ring current had been inferred from the variations of the Sym-H index, but as it turns out, those variations represent the dynamics of only the low-energy protons,” said Gkioulidou. “When we looked at the high-energy proton data from the RBSPICE instrument, however, we saw that they were behaving in a very different way, and the two populations told very different stories about the ring current.”
The Van Allen Probes, launched in 2012, offer scientists the first chance in recent history to continuously monitor the ring current with instruments that can observe ions with an extremely wide range of energies. The RBSPICE instrument has captured detailed data of all types of these energetic ions for several years. “We needed to have an instrument that measures the broad energy range of the particles that carry the ring current, within the ring current itself, for a long period of time,” Gkioulidou said. A period of one year from one of the probes was used for the team’s research.
“After looking at one year of continuous ion data it became clear to us that there is a substantial, persistent ring current around the Earth even during non-storm times, which is carried by high-energy protons. During geomagnetic storms, the enhancement of the ring current is due to new, low-energy protons entering the near-Earth region. So trying to predict the storm-time ring current enhancement while ignoring the substantial pre-existing current is like trying to describe an elephant after seeing only its feet,” Gkioulidou said.
The Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, built and operates the Van Allen Probes for NASA’s Science Mission Directorate. RBSPICE is operated by the New Jersey Institute of Technology in Newark, New Jersey. The mission is the second mission in NASA’s Living With a Star program, managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
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