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Tuesday, July 7, 2015

Where Are Earth's Meteorite Craters? 340 Waiting To Be Discovered

The geologists Prof. Dr. Stefan Hergarten and Prof. Dr. Thomas Kenkmann from the Institute of Earth and Environmental Sciences of the University of Freiburg have published the world’s first study on the question of how many meteorite craters there should be on the Earth’s surface. 

Gosses Bluff Impact Crater, Northern Territory, Australia
Astronaut photograph ISS007-E-05697 was taken with an Electronic Still Camera on May 20, 2003 with a 180-mm lens and is provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center

A total of 188 have been confirmed so far, and 340 are still awaiting discovery according to the results of a probability calculation presented by the two researchers in the journal Earth and Planetary Science Letters.

Germany’s Ries Crater (or Nördlinger Ries) is not easily discerned in space-based images. The crater’s existence was probably just as subtle to the medieval Europeans who established a settlement inside it and unknowingly matched their 1-kilometer- (0.6-mile-) wide city to the likely diameter of the meteorite that formed the crater.
NASA image created by Jesse Allen, using data provided courtesy of NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team.

Meteorite impacts have shaped the development of the Earth and life repeatedly in the past. The extinction of the dinosaurs, for instance, is thought to have been brought on by a mega-collision at the end of the Cretaceous period. But how many traces of large and small impacts have survived the test of time? 

In comparison to the more than 300,000 impact craters on Mars, the mere 188 confirmed craters on Earth seem almost negligible. Moreover, 60 of them are buried under sediments. Advances in remote sensing have not led to the expected boom in crater discoveries: An average of only one to two meteorite craters are discovered per year, most of them already heavily eroded.

Mars craters
Credit: NASA

The probability of a meteorite impact on Earth is not fundamentally different than on Mars. However, the Earth’s surface changes much more quickly. As a result, the craters remain visible for a much shorter period of time, meaning that many less of them are detectable today. “The main challenge of the study was to estimate the long-term effect of erosion, which causes craters to disappear over time,” says Hergarten. 

The life span of a crater depends on the rate of erosion and its size. Large craters can achieve a life span of several 100 million years, depending on the region in which they are located. On the other hand, large impacts are much rarer than small impacts. The solution was to compare the amount of confirmed craters of different sizes, calculate the expected frequency of the impacts on the basis of the known probabilities, and combine this information to infer the rates of erosion.

The meteor crater in Arizona, USA, with a diameter of 1.2 kilometers, is the most well-known impact crater. There must still be many undiscovered craters in this size category – but they are older and much less well preserved.
Image courtesy the National Map Seamless Server.

“A surprising, initially sobering finding we made was that there are not many craters of above six kilometers in diameter left to discover on the Earth’s surface,” reports Hergarten. In the case of smaller craters, on the other hand, the scientists found the current list to be far from complete: Around 90 craters with a diameter of one to six kilometers and a further 250 with a diameter of 250 to 1000 meters are still awaiting discovery. While there are undoubtedly still a number undiscovered large craters buried deep under sediments, they are much more difficult to detect and confirm.

Goat Paddock Crater, located on the Kimberley Plateau of northwestern Australia, appears to straddle the simple-complex category, according to a study published in 2005.
Credit: NASA Earth Observatory image created by Jesse Allen and Robert Simmon

Freiburg students have been involved in the research since 2011: The course “Screening Earth – a Student (Re)search Project” is held each year for master’s students in Geology. The course enables aspiring young geologists to participate in the search for undiscovered craters. “The students will have to decide for themselves whether to focus on looking for small craters – or whether it might yet be possible to pull off the coup of discovering one of the last remaining large meteorite craters,” says Kenkmann, who received the Baden-Württemberg State Teaching Award for the course in 2012.

Contacts and sources:
Prof. Dr. Stefan Hergarten
Institute of Earth and Environmental Sciences
University of Freiburg

Prof. Dr. Thomas Kenkmann
Institute of Earth and Environmental Sciences
University of Freiburg

Citation: S. Hergarten & T. Kenkmann (2015) The number of impact craters on Earth: Any room for further discoveries? Earth Planet. Sci. Lett., 425: 187-192. doi 10.1016/j.epsl.2015.06.009

Monday, July 6, 2015

From Satellite Swarms to Interstellar Submarines, NASA Selects Leading-Edge Technology Concepts for Continued Study

NASA has selected seven technology proposals for continued study under Phase II of the agency's Innovative Advanced Concepts (NIAC) Program. The selections are based on the potential to transform future aerospace missions, introduce new capabilities or significantly improve current approaches to building and operating aerospace systems.

Montage of several newly awarded NIAC Phase II concepts from fellows Bruce Wiegmann, Adrian Stoica, Steven Oleson, and Justin Atchison.
NIAC concepts
Credits: L to R, B. Wiegmann/MSFC, A. Stoica/JPL, S. Oleson, J. Atchison

The selected proposals address a range of visionary concepts, including metallic lithium combustion for long-term robotics operations, submarines that explore the oceans of icy moons of the outer planets, and a swarm of tiny satellites that map gravity fields and characterize the properties of small moons and asteroids.

"NASA's investments in early-stage research are important for advancing new systems concepts and developing requirements for technologies to enable future space exploration missions," said Steve Jurczyk, associate administrator for the Space Technology Mission Directorate at NASA Headquarters in Washington. "This round of Phase II selections demonstrates the agency's continued commitment to innovations that may transform our nation's space, technology and science capabilities."

NIAC Phase II awards can be worth as much as $500,000 for a two-year study, and the awards allow proposers to further develop their concepts from previously-selected Phase I studies. Phase I studies must demonstrate the initial feasibility and benefit of a concept. Phase II studies allow awardees to refine their designs and explore aspects of implementing the new technology.

NASA selected these projects through a peer-review process that evaluated innovativeness and technical viability. All projects are still in the early stages of development, most requiring 10 or more years of concept maturation and technology development before use on a NASA mission.

"This is an excellent group of NIAC studies," said Jason Derleth, NIAC Program executive at NASA Headquarters. "From seeing into cave formations on the moon to a radically new kind of solar sail that uses solar wind instead of light, NIAC continues to push the bounds of current technology."

NASA's Space Technology Mission Directorate innovates, develops, tests and flies hardware for use in future missions. Through programs such as NIAC, the directorate is demonstrating that early investment and partnership with scientists, engineers and citizen inventors from across the nation can provide technological dividends and help maintain America's leadership in the new global technology economy.

Contacts and sources:
Cynthia M. O'Carroll
Goddard Space Flight Center

Safer, with More Benefits: Parents' Vaccine Views Shifting

A quarter of parents believe vaccines are safer now than they thought a year ago; a third more supportive of school and daycare immunization requirements.

What do parents think of vaccine safety now compared to what they thought a year ago?
Credit: C.S. Mott Children's Hospital National Poll on Children's Health

Over the same time period that multiple outbreaks of measles and whooping cough made headlines around the country, parents' views on vaccines became more favorable, according to a new nationally-representative poll.

The University of Michigan C.S. Mott Children's Hospital National Poll on Children's Health asked parents in May how their views on vaccinations changed between 2014 and 2015 - during which two dozen measles outbreaks were reported in the U.S., including a multi-state outbreak traced to Disneyland.

One-third of parents who participated in the poll indicated they now perceived more benefits of vaccines, while one-quarter perceived vaccines to be safer now than a year ago. One--third of parents also reported being more supportive of school and daycare entry requirements for vaccination than they were the previous year.

The University of Michigan C.S. Mott Children's Hospital National Poll on Children's Health asked parents in May how their views on vaccinations changed between 2014 and 2015 -- during which two dozen measles outbreaks were reported in the US, including a multi-state outbreak traced to Disneyland.

Credit: University of Michigan Health System

"Over the last year there have been high-profile news stories about outbreaks of vaccine-preventable diseases like measles and whooping cough. These news reports may be influencing how parents perceive childhood vaccines across the country," says Matthew M. Davis, M.D., M.A.P.P., director of the National Poll on Children's Health and professor of pediatrics and internal medicine in the Child Health Evaluation and Research Unit at the U-M Medical School.

"For a quarter to a third of parents to say that their views on the safety and benefits of vaccines have shifted in just a year's time is quite remarkable. Parents' perceptions that vaccines are safer and offer more benefits are also consistent their stronger support of daycare and school entry requirements for immunizations."

Parents were also asked their opinions about the risk of measles and whooping cough compared to a year ago. Two out of every five parents, or 40 percent, believe the risk of measles for children in the U.S. is higher than what it was one year ago. Another 45 percent say the risk is about the same and 15 percent say the risk is lower.

A resurgence of whooping cough and measles over the last few years has triggered a national debate over vaccinations and garnered ongoing media coverage. On June 30, California Gov. Jerry Bill signed a bill to impose one of the nation's strictest vaccination laws following the outbreak linked to Disneyland in December 2014 that sickened more than 100 people. A surge in vaccine-preventable disease outbreaks have also spanned across the country from New York to Michigan to Washington State.

The majority of parents polled believe vaccines have the same benefits as a year ago and think the safety of vaccines has stayed the same. A minority of parents also had less favorable views on vaccines, with 7 percent perceiving less safety, 5 percent perceiving fewer benefits and 6 percent saying they were less supportive of school and daycare entry requirements that the previous year.

"Outbreaks of disease can safely be prevented through childhood vaccination, but there are deeply-held convictions about parents' autonomy and remaining concerns among some parents about vaccine safety," says Davis, who is also with the U-M School of Public Health, Gerald R. Ford School of Public Policy, and deputy director for U-M's Institute for Healthcare Policy and Innovation.

"Media coverage of outbreaks over the past year, accompanied by messages about vaccines for whooping cough and measles, may be swaying parents' opinions toward stronger beliefs in the positive aspects of vaccines. The impact of such shifts in perception will ultimately be measured by whether more parents vaccinate their kids."

Contacts and sources:
Beata Mostafavi
University of Michigan Health System

Autonomous Taxis Could Deliver Significant Environmental and Economic Benefits

Imagine a fleet of driverless taxis roaming your city, ready to pick you up and take you to your destination at a moment's notice. While this may seem fantastical, it may be only a matter of time before it becomes reality. And according to a new study from Lawrence Berkeley National Laboratory (Berkeley Lab), such a system would both be cost-effective and greatly reduce per-mile emissions of greenhouse gases.

Berkeley Lab researchers Jeff Greenblatt (left) and Samveg Saxena.

Credit:  Berkeley Lab  

The analysis found that the per-mile greenhouse gas emissions of an electric vehicle deployed as a self-driving, or autonomous, taxi in 2030 would be 63 to 82 percent lower than a projected 2030 hybrid vehicle driven as a privately owned car and 90 percent lower than a 2014 gasoline-powered private vehicle. Almost half of the savings is attributable to "right-sizing," where the size of the taxi deployed is tailored to each trip's occupancy needs.

The results were published online today by Nature Climate Change in an article titled, "Autonomous taxis could greatly reduce greenhouse gas emissions of U.S. light-duty vehicles," co-authored by Berkeley Lab scientists Jeffery Greenblatt and Samveg Saxena.

"When we first started looking at autonomous vehicles, we found that, of all the variables we could consider, the use of autonomous vehicles as part of a shared transit system seemed to be the biggest lever that pointed to lower energy use per mile," said Greenblatt.

Many automakers and other companies are working on autonomous cars. Right-sizing is cost-effective for both the fleet owner and for passengers, and small one- and two-seat vehicles are being explored by researchers and companies. To illustrate the concept, consider a single passenger with no luggage versus a party of four passengers with suitcases. The single passenger would require a much smaller taxi than the party of four, saving money for vehicle owners and passengers. Right-sizing, of course, assumes a fleet of taxis managed by a single entity.

"Most trips in the U.S. are taken singly, meaning one- or two-seat cars would satisfy most trips," Greenblatt said. "That gives us a factor of two savings, since smaller vehicles means reduced energy use and greenhouse gas emissions."

Another factor contributing to lower emissions for autonomous taxis is a cleaner electric grid. By 2030 power plants are expected to be using more renewable energy and emitting less pollution, meaning the greenhouse gas intensity of electricity will be lower.

Self-driving cars have additional efficiencies that have been covered in other research, such as the ability to drive closely behind other autonomous cars to reduce wind resistance ("platooning"), optimally routing trips, and smoother acceleration and braking. "These are all incremental, but they do add up," Greenblatt said. "However, we didn't even include these effects in our baseline results, and we still get huge savings without them."

The researchers also conducted an economic analysis to determine how cost-effective autonomous taxis would be. At 12,000 miles per year, the average distance traveled in the U.S. for privately owned cars, electric vehicles in 2030 are still expected to be more expensive than owning and operating a gasoline-powered car, the study found.

But if the vehicle is driven 40,000 to 70,000 miles per year, typical for U.S. taxis, they found that an alternative-fuel vehicle (hydrogen fuel cell or electric battery) was the most cost-effective option. This was based on costs for maintenance, fuel, insurance, and the actual cost of the vehicle (assuming a five-year loan). The reason is that despite the higher cost of a more efficient vehicle, the per-mile cost of fuel is lower, so the savings can pay for the extra investment.

"You don't often find that, where the cheapest is also the greenest," Greenblatt said.

While autonomous technology is currently estimated to add as much as $150,000 to the cost of a vehicle, an autonomous taxi using today's technology would still be cheaper than an ordinary taxi not simply due to its greater energy efficiency, but also due to the fact that no operator would be required. By 2030, autonomous taxis could be far cheaper than their driven counterparts.

The scientists did not try to estimate how widespread this technology would be in 2030. However, they did calculate that if five percent of 2030 vehicle sales (about 800,000 vehicles) were shifted to autonomous taxis, it would save about 7 million barrels of oil per year and reduce annual greenhouse gas emissions by between 2.1 and 2.4 million metric tons of CO2per year, equal to the emissions savings from more than 1,000 two-megawatt wind turbines.

To estimate the number of trips taken by different numbers of occupants, the researchers analyzed National Household Travel Survey data from the Federal Highway Administration. The scientists then modeled hypothetical one- and two-seat vehicles based on Nissan Leaf parameters driving three test-drive cycles as defined by the Environmental Protection Agency (EPA) using Autonomie, a vehicle-modeling tool developed by Argonne National Laboratory that simulates energy consumption on a second-by-second basis.

Furthermore, the scientists explored the net energy effect of combining ride-sharing with right-sized autonomous taxis. For example, if 10 percent of one-person rides were shifted to two-person rides, the total miles traveled would decrease 3.1 percent while average energy consumption (due to the larger vehicle) would increase 0.6 percent, resulting in a net energy decrease of 2.5 percent.

Greenblatt said plans for further study on this topic are in the works, including exploring the effect of battery degradation, looking at optimal vehicle designs, and making a more realistic simulation of how a fleet of autonomous taxis would actually operate in a metropolitan area.

Contacts and sources:
Julie ChaoLawrence Berkeley National Laboratory (Berkeley Lab)

Surfing a Wake of Light: Researchers Observe and Control Light Wakes for the First Time

When a duck paddles across a pond or a supersonic plane flies through the sky, it leaves a wake in its path. Wakes occur whenever something is traveling through a medium faster than the waves it creates -- in the duck's case water waves, in the plane's case shock waves, otherwise known as sonic booms.

This is an artistic rendition of the superluminal running wave of charge that excites the surface plasmon wakes.

Credit: Daniel Wintz, Patrice Genevet, and Antonio Ambrosio 

Wakes can exist wherever there are waves, even if those waves are light. While nothing travels faster than the speed of light in a vacuum, light isn't always in a vacuum. It is possible for something to move faster than the phase velocity of light in a medium or material and generate a wake. The most famous example of this is Cherenkov radiation, wakes produced as electrical charges travel through liquids faster than the phase velocity of light, emitting a glowing blue wake.

For the first time, Harvard researchers have created similar wakes of light-like waves moving on a metallic surface, called surface plasmons, and demonstrated that they can be controlled and steered. The discovery, published today in the journal Nature Nanotechnology, was made in the lab of Federico Capasso, the Robert L. Wallace Professor of Applied Physics and Vinton Hayes Senior Research Fellow in Electrical Engineering at the Harvard John A. Paulson School of Engineering and Applied Science (SEAS).

"The ability to control light is a powerful one," said Capasso. "Our understanding of optics on the macroscale has led to holograms, Google Glass and LEDs, just to name a few technologies. Nano-optics is a major part of the future of nanotechnology and this research furthers our ability to control and harness the power of light on the nanoscale."

The creation and control of surface plasmon wakes could lead to new types of plasmonic couplers and lenses that could create two-dimensional holograms or focus light at the nanoscale.

Surface plasmons are confined to the surface of a metal. In order to create wakes through them, Capasso's team designed a faster-than-light running wave of charge along a one-dimensional metamaterial -- like a powerboat speeding across a lake.

The metamaterial, a nanostructure of rotated slits etched into a gold film, changes the phase of the surface plasmons generated at each slit relative to each other, increasing the velocity of the running wave. The nanostructure also acts like the boat's rudder, allowing the wakes to be steered by controlling the speed of the running wave.

The team discovered that the angle of incidence of the light shining onto the metamaterial provides an additional measure of control and using polarized light can even reverse the direction of the wake relative to the running wave -- like a wake traveling in the opposite direction of a boat.

"Being able to control and manipulate light at scales much smaller than the wavelength of the light is very difficult," said Daniel Wintz, a lead author of the paper and graduate student in the Capasso lab. "It's important that we not only observed these wakes but found multiple ways to control and steer them."

The observation itself was challenging, as "surface plasmons are not visible to the eye or cameras," said co-lead author Antonio Ambrosio of SEAS and the Italian Research Council (CNR). "In order to view the wakes, we used an experimental technique that forces plasmons from the surface, collects them via fiber optics and records the image."

This work could represent a new testbed for wake physics across a variety of disciplines. "This research addresses a particularly elegant and innovative problem in physics which connects different physical phenomena, from water wakes to sonic booms, and Cherenkov radiation," said Patrice Genevet, a lead author, formerly of SEAS, currently affiliated with the Singapore Institute of Manufacturing Technology.

Contacts and sources:
Leah Burrows
Harvard University

Hidden Population of Supermassive Black Holes Revealed

Astronomers have found evidence for a large population of hidden supermassive black holes in the Universe.

Using NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) satellite observatory, the team of international scientists detected the high-energy x-rays from five supermassive black holes previously clouded from direct view by dust and gas.

An artist's illustration of a supermassive black hole, actively feasting on its surroundings. The central black hole is hidden from direct view by a thick layer of encircling gas and dust.

Credit: NASA/ESA 

The research, led by astronomers at Durham University, UK, supports the theory that potentially millions more supermassive black holes exist in the Universe, but are hidden from view.

The findings are being presented at the Royal Astronomical Society's National Astronomy Meeting, in Llandudno, Wales, today (Monday, July 6, 2015).

The scientists pointed NuSTAR at nine candidate hidden supermassive black holes that were thought to be extremely active at the centre of galaxies, but where the full extent of this activity was potentially obscured from view.

High-energy x-rays found for five of the black holes confirmed that they had been hidden by dust and gas. The five were much brighter and more active than previously thought as they rapidly feasted on surrounding material and emitted large amounts of radiation.

Such observations were not possible before NuSTAR, which launched in 2012 and is able to detect much higher energy x-rays than previous satellite observatories.

An illustration of the NuSTAR satellite observatory in orbit. The unique 10-meter-long mast allows NuSTAR to focus high-energy X-rays.

Credit:  NASA/JPL-Caltech

Lead author George Lansbury, a postgraduate student in the Centre for Extragalactic Astronomy, at Durham University, said: "For a long time we have known about supermassive black holes that are not obscured by dust and gas, but we suspected that many more were hidden from our view.

"Thanks to NuSTAR for the first time we have been able to clearly see these hidden monsters that are predicted to be there, but have previously been elusive because of their 'buried' state.

"Although we have only detected five of these hidden supermassive black holes, when we extrapolate our results across the whole Universe then the predicted numbers are huge and in agreement with what we would expect to see."

A Hubble Space Telescope color image of one of the nine galaxies targeted by NuSTAR. The high-energy X-rays detected by NuSTAR revealed the presence of an extremely active supermassive black hole at the galaxy center, deeply buried under a blanket of gas and dust.

Credit:  Hubble Legacy Archive, NASA, ESA

Daniel Stern, the project scientist for NuSTAR at NASA's Jet Propulsion Laboratory in Pasadena, California, added: "High-energy X-rays are more penetrating than low-energy X-rays, so we can see deeper into the gas burying the black holes. NuSTAR allows us to see how big the hidden monsters are and is helping us learn why only some black holes appear obscured."

The research was funded by the Science and Technology Facilities Council (STFC) and has been accepted for publication in The Astrophysical Journal.

Contacts and sources:
Leighton Kitson
Durham University

Friday, July 3, 2015

How Our Sense of Smell Evolved, Including in Cave Men

A group of scientists led by Dr Kara Hoover of the University of Alaska Fairbanks and including Professor Matthew Cobb of The University of Manchester, has studied how our sense of smell has evolved, and has even reconstructed how a long-extinct human relative would have been able to smell.

The sense of smell plays a decisive role in human societies, as it is linked to our taste for food, as well as our identification of pleasant and unpleasant substances. 

Credit: University of Delaware 

We have about 4 million smell cells in our noses, divided into about 400 different types. There is tremendous genetic variability within and between populations for our ability to detect odours. Each smell cell carries just one type of receptor or 'lock' on it - the smell floats through the air, fits into the 'lock' and then activates the cell.

Most receptors can detect more than one smell, but one, called OR7D4, enables us to detect a very specific smell called androstenone, which is produced by pigs and is found in boar meat. People with different DNA sequences in the gene producing the OR7D4 receptor respond differently to this smell - some people find it foul, some sweet, and others cannot smell it at all. People's responses to androstenone can be predicted by their OR7D4 DNA sequence, and vice versa.

Professor Cobb from The University of Manchester’s Faculty of Life Sciences and the other researchers studied the DNA that codes for OR7D4 from over 2,200 people from 43 populations around the world, many of them from indigenous groups. They found that different populations tend to have different gene sequences and therefore differ in their ability to smell this compound.

For example, they found that populations from Africa - where humans come from - tend to be able to smell it, while those from the northern hemisphere tend not to. This shows that when humans first evolved in Africa, they would have been able to detect this odour.

Statistical analysis of the frequencies of the different forms of the OR7D4 gene from around the world suggested that the different forms of this gene might have been subject to natural selection.

One possible explanation of this selection is that the inability to smell androstenone was involved in the domestication of pigs by our ancestors - andostroneone makes pork from uncastrated boars taste unpleasant to people who can smell it. Pigs were initially domesticated in Asia, where genes leading to a reduced sensitivity to androstenone have a high frequency.

The group also studied the OR7D4 gene in the ancient DNA from two extinct human populations, Neanderthals and the Denisovans, whose remains were found at the same site in Siberia, but who lived tens of thousands of years apart.

The group found that Neanderthal OR7D4 DNA was like our own - they would have been able to smell androstenone. The Denisovans are a mysterious group of our extinct relatives - we do not know what they looked like, and they are known from only one tooth and a finger bone, from different individuals.

Their DNA showed a unique mutation, not seen in humans or Neanderthals, that changed the structure of the OR7D4 receptor.

Team-member Hiroaki Matsunami at Duke University in the USA reconstructed the Denisovan OR7D4 and studied how this tiny part of a long-extinct nose responded to androstenone. It turned out that despite the mutation, the Denisovan nose functioned like our own. Both of our close relatives, like our early human ancestors, would have been able to detect this strange smell.

This research shows how global studies of our genes can give insight into how our taste for different foods may have been influenced by variation in our ability to smell, and, excitingly, show that it is possible to see back into deep evolutionary time and reconstruct the sensory world of our distant ancestors.

The research was carried out by scientists from the University of Alaska Fairbanks, State University of New York, Duke University and The University of Manchester, and is published in the journal Chemical Senses.

Contacts and sources:
Jamie BrownManchester University

Citation:  Kara C. Hoover, Omer Gokcumen, Zoya Qureshy, Elise Bruguera, Aulaphan Savangsuksa, Matthew Cobb and Hiroaki Matsunami, Global Survey of Variation in a Human Olfactory Receptor Gene Reveals Signatures of Non-Neutral Evolution, Chem. Senses first published online June 13, 2015, doi: 10.1093/chemse/bjv030

How Dementia Sufferers Benefit from GPS

A brand new study of 200 dementia sufferers in Norway reveals that almost all experience greater peace of mind and increased levels of physical activity using GPS devices.

The study relates the story of an elderly man residing in the secure ward of a nursing home who was not allowed to go out because he always got lost. He wasted a lot of energy getting up and shaking the door, and minor conflicts always arose when staff had to lead him away.

The study has confirmed that dementia sufferers can maintain their independence, enjoy their freedom and continue to pursue their outdoor activities in spite of the development of their illness. 

Photo: Henning Tunsli

One nurse intervened and decided that during her shift the patient should be given a GPS device and allowed out. The man went for a walk, visited a café, sat for while watching the people go by, and then returned home. If he failed to return, it was easy to find him and bring him back. After a while, three of the patients on this ward were given GPS devices. Things calmed down and staff found that they had more time to take care of those patients who didn't venture out.

Documentation is vital

The study forms part of the public sector innovation projects collectively known as "Trygge Spor og Samspill" (Safe tracking and interaction) – a joint initiative launched in 2011 being carried out by SINTEF together with a number of Norwegian municipalities. The initial project began with five municipalities and 50 dementia sufferers, and in 2015 it was expanded to include 18 municipalities. People with dementia (or cognitive dysfunction) taking part in the study have experience in using the devices varying from three months to two years.

A survey has been incorporated into the study involving device users, next of kin and personnel employed by all of the 18 municipalities as respondents. Interviews have also been conducted. All forms of data can provide useful background information as a basis for the planning and use of GPS technology as part of health care provision in Norway. 

Previously, it has been difficult to substantiate the benefits of using GPS devices, and this is why the documentation of experience reported by municipalities is key to the work currently being carried out.

Independence and peace of mind

"We have seen many positive benefits", say Tone Øderud and Dag Ausen at SINTEF. "The study has confirmed that dementia sufferers can maintain their independence, enjoy their freedom and continue to pursue their outdoor activities in spite of the development of their illness", they say.

More or less all respondents to the survey (next of kin, GPS users, health service providers and staff at out-patient clinics and nursing homes) say that the GPS devices give them greater peace of mind. Staff at the clinics and homes experience fewer conflicts and waste less time and effort in redirecting patients and keeping order on the wards. 

Moreover, the technology can result in financial savings in cases where sufferers are able to live for longer at home or can reside in open, as opposed to secure, nursing home wards. Only very few feel that they are under surveillance.

There is also the direct benefit of enabling next of kin carers to spend more time at work.

Who benefits?

During the three years that SINTEF researchers have been gathering data from the municipalities, they have acted as project supervisors and have obtained a wealth of research-based insights.

"It is vital to identify who is best suited to use the GPS devices", says Tone Øderud. "This type of technology doesn't suit everyone", she says. The municipalities are currently carrying out a survey with the aim of identifying and establishing an overview of their GPS users. Who are the users? Where do they live? Why were they given the technology? How is the service set up? Guidelines provided here may make it possible to weed out those who will not benefit from the technology.

"It's important to realise that not every municipality has to have the same experiences or dedicate resources to these issues", says Ausen. "For example, we know that Drammen municipality has worked with this issue for some time and has become increasingly more adept at 'getting it right'. When a candidate is identified and registered with a request for a GPS device, municipal staff can decide quickly as to whether or not he or she will benefit from the technology. In some cases, a municipality has been able to postpone transfer to a nursing home by as much as six months", he says.

Extending a good life

Not all the GPS users in the study have received a dementia diagnosis, but all are suffering from dementia-related problems with cognitive dysfunction.

The assistance provided by a GPS device will not last in the long term. Nevertheless, its function is important to sufferers for as long as it works", says Dag Ausen. "So far during the study the average period of use has been between 10 and 11 months", he says.

The study reveals that between 20 and 25% of sufferers who report benefits from using GPS also obtain a direct benefit from being able to live longer at home. If their functioning deteriorates to the extent that they are unable to live at home, they can nevertheless reside in an open ward in a nursing home.

"For younger dementia sufferers, the use of a GPS device means that a spouse can spend more time at work and plan their day-to-day routines better", says Øderud.

She tells the story of a younger couple taking part in the study in which the wife became worried when her husband started getting lost on his journey home. She wanted him to have a GPS device, but at first he didn't feel he needed it. Today, she can go to work while her husband spends his mornings going for walks or cycling with his GPS device. If he doesn't get home for dinner, she can find out where he is. By then he will be tired and exhausted.

The couple have been granted the technology by the municipality as a preventive measure. This can be particularly useful for young and fit people who want to keep active.

Regular routines

In conclusion, there is no doubt that people suffering from dementia who would still rather go out than sit inside can live an active life much as they did before, and as safely as possible.

The study provides evidence that it is important that dementia sufferers, their next of kin carers, and professional care providers all work together. This ensures that the GPS technology works successfully, and means that dementia sufferers can be located in an appropriate manner.

The researchers emphasise that it is important to establish regular routines. Most sufferers find it useful to have the GPS device by the door, and then hang it round their neck or put it in their pocket when they go out. Some have learned how to charge their devices, while others rely on next of kin or visiting nurses for supervision and assistance.

Close supervision is important for GPS users, and it varies from person to person as to who they think can help them best among their next of kin, social services, volunteers and suchlike. The most important thing is that roles are clearly defined and the service robust.

Contacts and sources:

New Lithium Ion Battery Is Safer, Tougher, and More Powerful

Lithium ion batteries (LIBs) are a huge technological advancement from lead acid batteries which have existed since the late 1850’s. Thanks to their low weight, high energy density and slower loss of charge when not in use, LIBs have become the preferred choice for consumer electronics. 

 Lithium-ion cells with cobalt cathodes hold twice the energy of a nickel-based battery and four-times that of lead acid. Despite being a superior consumer battery, LIBs still have some drawbacks. Current manufacturing technology is reaching the theoretical energy density limit for LIBs and overheating leading to thermal runaway i.e. “venting with flame” is a serious concern.

Simple incorporation of various lithium precursor to porous CB[6] exhibits high lithium ion conductivities, mobility and safer dried solid lithium electrolytes

South Korean researchers at the Center for Self-assembly and Complexity, Institute for Basic Science (IBS), Department of Chemistry and Division of Advanced Materials Science at Pohang University, have created a new LIB made from a porous solid which greatly improves its performance as well as reducing the risks due to overheating.

Since 2002 there have been over 40 recalls in the US alone due to fire or explosion risk from LIBs used in consumer electronic devices. These types of batteries, in all of their different lithium-anode combinations, continue to be an essential part of modern consumer electronics despite their poor track record at high temperatures.

The Korean team tried a totally new approach in making the batteries. According to Dr. Kimoon Kim at IBS, “we have already investigated high and highly anisotropic [directionally dependent] proton conducting behaviors in porous CB[6] for fuel cell electrolytes. It is possible for this lithium ion conduction following porous CB[6] to be safer than existing solid lithium electrolyte -based organic-molecular porous-materials utilizing the simple soaking method.” 

Current LIB technology relies on intercalated lithium which functions well, but due to ever increasing demands from electronic devices to be lighter and more powerful, investigation of novel electrolytes is necessary in order.

The new battery is built from pumpkin-shaped molecules called cucurbit[6]uril (CB[6]) which are organized in a honeycomb-like structure. The molecules have an incredibly thin 1D-channel, only averaging 7.5 Å [a single lithium ion is 0.76 Å, or .76 x 10-10 m] that runs through them. The physical structure of the porous CB[6] enables the lithium ions to battery to diffuse more freely than in conventional LIBs and exist without the separators found in other batteries.

In tests, the porous CB[6] solid electrolytes showed impressive lithium ion conductivity. To compare this to existing battery electrolytes, the team used a measurement of the lithium transference number (tLi+) which was recorded at 0.7-0.8 compared to 0.2-0.5 of existing electrolytes. They also subjected the batteries to extreme temperatures of up to 373 K (99.85° C), well above the 80° C typical upper temperature window for exiting LIBs. In the tests, the batteries were cycled at temperatures between 298 K and 373 K ( 24.85° C and 99.85° C) for a duration of four days and after each cycle the results showed no thermal runaway and hardly any change in conductivity.

Various conventional liquid electrolytes can incorporate in a porous CB[6] framework and converted to safer solid lithium electrolytes. Additionally, electrolyte usage is not limited to use only in LIBs, but a lithium air battery potentially feasible. What makes this new technique most exciting is that it is a new method of preparing a solid lithium electrolyte which starts as a liquid but no post-synthetic modification or chemical treatment is needed.

Contacts and sources:
By Daniel Kopperud
Institute for Basic Science

Citation: Jun Heuk Park, Kyungwon Suh, Md. Rumum Rohman, Wooseup Hwang, Minyoung Yoon and Kimoon Kim, (2015), “Solid lithium electrolytes based on an organic molecular porous solid”, The Royal Society of Chemistry, DOI: 10.1039/c5cc02581h

A Stretchy Mesh Heater for Sore Muscles

If you suffer from chronic muscle pain a doctor will likely recommend for you to apply heat to the injury. But how do you effectively wrap that heat around a joint? Korean Scientists at the Center for Nanoparticle Research, Institute for Basic Science (IBS) in Seoul, along with an international team, have come up with an ingenious way of creating therapeutic heat in a light, flexible design.

To ensure that the material remains tight on the target area while heating, the team devised a 2-D interlocking coil pattern for the mesh structure. To make the mesh, the liquid mixture was poured into a shaped mold. The silver-elastic mesh was sandwiched between a top and bottom layer of soft, thin insulation.
Credit: Institute for Basic Science

Other teams have come up with similar devices before, although no one was able to create something that didn’t rely on exotic materials or a complex fabrication process, factors which both carry hefty price tags. Unlike their predecessors, the team at IBS stayed away from things like carbon nanotubes and gold and looked at a more utilitarian option for their build material: thin slivers of silver nanowires.

The silver nanowires are tiny, averaging ∼150 nm in diameter and ∼30 μm in length (a human hair ranges from 17 to 181 µm). The nanowires were mixed into a liquid elastic material which is both soft and stretchy when dry.

(Left: mesh in a relaxed state Right: Mesh stretched over a curve to 100%)

Credit: Institute for Basic Science

To ensure that the material remains tight on the target area while heating, the team devised a 2-D interlocking coil pattern for the mesh structure. To make the mesh, the liquid mixture was poured into a shaped mold. The silver-elastic mesh was sandwiched between a top and bottom layer of soft, thin insulation.

In material flexibility tests, while placed on knee and wrist joints, the mesh heated while deformed and under stress on knee and wrist joints. It is lightweight, breathable and generates heat over the entire surface area of the material. A hot water bottle used for treating muscle soreness feels good, but it will inevitably cool down while in use. 

 Commercially available electric heating pads are sufficient for applying heat to an injured area but their cords need to be attached to an A/C outlet to work. This is where the new technology trumps the old. The mesh maintains a constant temperature instead of cooling down during use and is battery powered so it doesn’t need an outlet.

Beyond thermotherapy, the applications are endless. This technology could be used as a lightweight heating element in ski jackets, or as a hyper-efficient seat warmer in a car. Although only flat mesh connected into a tube has been made so far, it isn’t a stretch to imagine creating more intricate designs like the shape of a hand with detailed fingers.

Contacts and sources:
By Daniel Kopperud
Institute for Basic Science

Citation: Suji Choi, Jinkyung Park, Wonji Hyun, Jangwon Kim, Jaemin Kim, Young Bum Lee,Changyeong Song, Hye Jin Hwang, Ji Hoon Kim, Taeghwan Hyeon, and Dae-Hyeong Kim, (2015), “Stretchable Heater Using Ligand-Exchanged Silver Nanowire Nanocomposite for Wearable Articular Thermotherapy”, American Chemical Society, DOI: 10.1021/acsnano.5b02790

Panel Turns Window into a Solar Cell to Recharge Electronic Devices

The researcher Sandra Casillas from the Technological Institute of La Laguna (ITL), in the north of Mexico, has managed to patent 20 projects, and an example of her work is the design of two Tandem cells that turns windows into a solar panel capable of capturing up to eight volts per square meter of light and allows to recharge electronics. It is also transparent, allowing visibility.

Credit:  Investigación y Desarrollo

Sandra Casillas, professor of the ITL in Torreon, Coahuila (northern state of Mexico) explains that for this project she combined two materials to create the cells and increase effectiveness when capturing energy. The first is made of copper and zinc, and the second of selenium and tellurium, the latter is more efficient due to the conducting characteristics of metals.

Its benefits are instant, just by placing it in the window and connecting both copper wires allows to make use of energy. The Tandem cells are 30 percent cheaper than conventional ones and only sold in Europe, referred to specialist.

Credit:  Investigación y Desarrollo

She adds that the square meter will cost 350 pesos, cheap compared to solar cells that increase the price because they need space to store energy.

The researcher says that creating the film of the cell was based on food packages, which consist of three layers. "We use this technology in the Tandem cell to generate transparent polymer layers".

She took as a reference the plastic SBS (Styrene-Butadiene-Styrene), which allows the passage of oxygen on both sides of the glass and allows to see through it, even if there is much humidity in the room it does not bead up. "What we did was to put nanoparticles of different materials and between the glass and the cell we placed a magnesium tunnel that stops the window from heating".

The specialist in materials engineering relates that this material was used after the attacks of September 11 in the United States. "The Americans did not like receiving vegetables in a packaging with holes, we used to send wrapped lettuce with polyethylene, which has those little holes to prevent oxidation, but had to resort to engineering to use another material with the same function, then the SBS came, it looks like polyethylene but allows the passage of oxygen and preserves vegetables".

Sandra Casillas, who organizes the Expo Science in Coahuila, and the north of Durango, says that there is little financial support for research at the upper secondary level and the industry at Torreon was who contributed to make the projects.

Such is the case of the Peñoles Industry (producer of minerals), which provided magnesium, selenium and tellurium metals for the two Tandem cells; however, the project has just received funding from the National Fund for Scientific Research and Technology (FONCyT), income spent on making the latest laboratory tests and obtain patents. (Agencia ID)

Contacts and sources:  
Investigación y Desarrollo

GHOST: Computer Screens That Change Shape for 3D Design - Video

Exciting new technologies, which allow users to change the shape of displays with their hands, promise to revolutionise the way we interact with smartphones, laptops and computers. Imagine pulling objects and data out of the screen and playing with these in mid-air.

Towards Rapid Prototyping with Shape-Changing Displays for Designers
Credit: © GHOST
Today we live in a world of flat-screen displays we use all day – whether it’s the computer in the office, a smartphone on the train home, the TV or iPad on the couch in the evening. The world we live in is not flat, though; it’s made of hills and valleys, people and objects. Imagine if we could use our fingertips to manipulate the display and drag features out of it into our 3D world.

Credit:   Københavns Universitets  

Such a vision led to the launch in January 2013 of GHOST (Generic, Highly-Organic Shape-Changing Interfaces), an EU-supported research project designed to tap humans’ ability to reason about and manipulate physical objects through the interfaces of computers and mobile devices.

‘This will have all sorts of implications for the future, from everyday interaction with mobile phones to learning with computers and design work,’ explained GHOST coordinator Professor Kasper Hornbæk of the University of Copenhagen. ‘It’s not only about deforming the shape of the screen, but also the digital object you want to manipulate, maybe even in mid-air. Through ultrasound levitation technology, for example, we can project the display out of the flat screen. And thanks to deformable screens we can plunge our fingers into it.’

Shape-changing displays you can touch and feel

This breakthrough in user interaction with technology allows us to handle objects, and even data, in a completely new way. A surgeon, for instance, will be able to work on a virtual brain physically, with the full tactile experience, before performing a real-life operation. Designers and artists using physical proxies such as clay can mould and remould objects and store them in the computer as they work. GHOST researchers are also working with deformable interfaces such as pads and sponges for musicians to flex to control timbre, speed and other parameters in electronic music.

Indeed, GHOST has produced an assembly line of prototypes to showcase shape-changing applications. ‘Emerge’ is one which allows data in bar charts to be pulled out of the screen by fingertips. The information, whether it’s election results or rainfall patterns, can then be re-ordered and broken down by column, row or individually, in order to visualise it better.

The researchers have also been working with ‘morphees’, flexible mobile devices with lycra or alloy displays which bend and stretch according to use. These can change shape automatically to form screens to shield your fingers when you type in a pincode, for example, or to move the display to the twists and turns of a game. And such devices can be enlarged in the hand to examine data closer and shrunk again for storing away in a case or pocket.

Tactile technology reaching the market

One of the GHOST partners, the University of Bristol, has spun off a startup, now employing 12 people, called UltraHaptics, to develop technology being studied in GHOST that uses ultrasound to create feeling in mid-air. The company has attracted seed investment in the UK and further funding from the Horizon 2020 programme.

‘GHOST has made a lot of progress simply by bringing the partners together and allowing us to share our discoveries,’ commented Prof Hornbæk. ‘Displays which change shape as you are using them are probably only five years off now. If you want your smartphone to project the landscape of a terrain 20 or 30 cm out of the display, that’s a little further off - but we’re working on it!’

GHOST, which finishes at the end of this year, involves four partners in the United Kingdom, Netherlands and Denmark, and receives EUR 1.93 million from the EU’s Future and Emerging Technologies programme.

Link to project's website:

Contacts and sources:

5G: Mobile Traffic Data Thousand-Fold Growth by 2020

Mobile data traffic is expected to grow hundred- or thousand-fold by 2020, when the new 5G telecoms standards are due to enter the market. As the race is on to come up with new solutions for telecoms networks to accommodate this massive growth, one EU research project has already developed an ultra-fast solution using optical transmission technology.

Credit: Thinkstock

LIGHTNESS, an industry-driven EU research project that started back in 2012, was set up to strengthen European technology for connecting data centres and anticipate the growing traffic between them. It is doing this by harnessing the improved power, speed and cost-efficiency of optical (over electrical) transmission.

‘The infrastructure we develop must scale upwards for 5G in a way that current grouped Ethernet switches won't be able to,’ explained Matteo Biancani, of Interoute, the telecoms and cloud services provider leading the project. ‘Scalability of the project is really the key word if we are to meet increased future demand.’

Data transmission at the speed of light

Even today’s 4G and 3G networks are seeing great demand for high data throughput and fast response times, due to the increasing use of high-performance computing, as well as cloud and server-side storage applications. This makes the work of the LIGHTNESS project immediately relevant, in addition to anticipating the advent of 5G technologies.

The main aim of LIGHTNESS has been to design innovative photonic switching and transmission techniques to establish high-performance, low-cost interconnects between and inside data centers. Specifically, universities and research facilities participating in the project, in the UK, Netherlands and Spain, have trialled Optical Circuit Switching (OCS) and Optical Packet Switching (OPS) in special test beds. The test beds simulate intra-data centre network environments and test the technology to see if it can fulfill the requirements of emerging applications in terms of ultra-high bandwidth and low network latency.

With scalability in mind, they have carried out a lot of studies and simulations to evaluate the benefits of LIGHTNESS architecture in very large deployments, using more than 100 different wavelength channels at the same time, resulting in bandwidth capacities of multiple terabits/second per fibre link. The use of OCS and OPS technologies together forms the most promising solution to switching huge data flows, literally at the speed of light.

Rates of 40 to 100 gigabits per second

In the test beds, the LIGHTNESS researchers developed an Optical Packet Switch (OPS), which indeed does provide the nanosecond latency that networks will need to respond to the demands of mobile users in the future. They have also trialed a ‘Top-of-Rack (ToR)’ switch, used for linking racks of storage equipment to the OPS/OCS data center network, aggregating traffic in both long-lived and short-lived data flows. LIGHTNESS has successfully tested these operations at speeds that have never before been seen in networks, ranging between 40 and 100 gigabits per second.

Deployment in data centre networks by 2018

Preliminary prototypes from the project were showcased at the European Conference on Networks and Communications in Paris last year, where LIGHTNESS won Best Booth Award in demonstrating its new software-defined Optical Data Centre Network (ODCN).

‘The full implementation of the LIGHTNESS hardware and software prototypes is now ready and is under experimental evaluation and validation in the project testbed. A full concept demonstration will take place next September at the European Conference on Optical Communications in Valencia. We are building equipment for deployment in our data center networks and production will peak in two to three years' time,’ said Matteo.

LIGHTNESS is a Specific Targeted Research Project receiving EUR 2.44 million investment from the EU’s 7th Framework Programme. It involves seven partners in Italy, the Netherlands, Spain and the United Kingdom, and ends in October this year.

Link to project's website:

Contacts and sources: 

South Africans Used Milk-Based Paint 49,000 Years Ago Says New Study

An international research team led by the University of Colorado Boulder and the University of Witwatersrand in Johannesburg, South Africa has discovered a milk-and ochre-based paint dating to 49,000 years ago that inhabitants may have used to adorn themselves with or to decorate stone or wooden slabs.

An international research team led by the University of Colorado Boulder and the University of Witwatersrand in Johannesburg, South Africa, has discovered a milk-and ochre-based paint on a small stone flake dating to 49,000 years ago that inhabitants may have used to adorn themselves with or to decorate stone or wooden slabs. The powdered paint mixture was found on the edge of of Sibudu Cave, a rock shelter in northern KwaZulu-Natal, Africa. 
Credit: CU Boulder

While the use of ochre by early humans dates to at least 250,000 years ago in Europe and Africa, this is the first time a paint containing ochre and milk has ever been found in association with early humans in South Africa, said Paola Villa, a curator at the University of Colorado Museum of Natural History and lead study author. The milk likely was obtained by killing lactating members of the bovid family such as buffalo, eland, kudu and impala, she said.

"Although the use of the paint still remains uncertain, this surprising find establishes the use of milk with ochre well before the introduction of domestic cattle in South Africa," said Villa. "Obtaining milk from a lactating wild bovid also suggests that the people may have attributed a special significance and value to that product."

The powdered paint mixture was found on the edge of a small stone flake in a layer of Sibudu Cave, a rock shelter in northern KwaZulu-Natal, Africa, that was occupied by anatomically modern humans in the Middle Stone Age from roughly 77,000 years ago to about 38,000 years ago, said Villa. While ochre powder production and its use are documented in a number of Middle Stone Age South African sites, there has been no evidence of the use of milk as a chemical binding agent until this discovery, she said.

A paper on the subject was published online June 30 in PLOS ONE. Co-authors were from the Italian Institute of Paleontology in Rome, Italy; the University of Geneva in Switzerland; the University of Pisa in Italy; the University of Monte St. Angelo in Naples, Italy; and the University of Oxford in England. The excavation was directed by Professor Lyn Wadley of the University of Witwatersrand, also a paper co-author.

Cattle were not domesticated in South Africa until 1,000 to 2,000 years ago, said Villa. Wild South African bovids are known to separate from the herd when giving birth and usually attempt to hide their young, a behavior that may have made them easy prey for experienced Middle Stone Age hunters, she said.

The dried paint compound is preserved on the stone flake that may have been used as a mixing implement to combine ochre and milk, or as an applicator, said Villa. The team used several high-tech chemical and elemental analyses to verify the presence of casein, the major protein of milk, on the flake.

At both African and European archaeological sites, scientists have found evidence of ochre -- a natural pigment containing iron oxide than can range from yellow and orange to red and brown - dating back 250,000 years. By 125,000 years ago, there is evidence ochre was being ground up to produce a paint powder in South Africa.

It has been proposed the ochre was sometimes combined by ancient Africans with resin or plant gum to use as an adhesive for attaching shafts to stone tools or wooden bone handles, Villa said. It also may have been used to preserve hides and for body paint, she said, noting that a roughly 100,000-year-old ochre-rich compound blended with animal marrow fat was found at the Middle Stone Age site of Blombos Cave in South Africa.

Body painting is widely practiced by the indigenous San people in South Africa, and is depicted in ancient rock art. While there are no ethnographic precedents for mixing ochre with milk as a body paint, the modern Himba people in Namibia mix ochre with butter as a coloring agent for skin, hair and leather clothing, Villa said.

Contact and sources:
Paola Villa
Jim Scott 

Thursday, July 2, 2015

Two Distinct Faces of Pluto, Series of Spots Fascinate Astronomers

New color images from NASA’s New Horizons spacecraft show two very different faces of the mysterious dwarf planet, one with a series of intriguing spots along the equator that are evenly spaced. Each of the spots is about 300 miles (480 kilometers) in diameter, with a surface area that’s roughly the size of the state of Missouri.

Scientists have yet to see anything quite like the dark spots; their presence has piqued the interest of the New Horizons science team, due to the remarkable consistency in their spacing and size. While the origin of the spots is a mystery for now, the answer may be revealed as the spacecraft continues its approach to the mysterious dwarf planet.

“It’s a real puzzle—we don’t know what the spots are, and we can’t wait to find out,” said New Horizons principal investigator Alan Stern of the Southwest Research Institute, Boulder. “Also puzzling is the longstanding and dramatic difference in the colors and appearance of Pluto compared to its darker and grayer moon Charon.”

New Horizons team members combined black-and-white images of Pluto and Charon from the spacecraft’s Long-Range Reconnaissance Imager (LORRI) with lower-resolution color data from the Ralph instrument to produce these views. 

We see the planet and its largest moon in approximately true color, that is, the way they would appear if you were riding on the New Horizons spacecraft. About half of Pluto is imaged, which means features shown near the bottom of the dwarf planet are at approximately at the equatorial line.

If Pluto has clouds, New Horizons can detect them. Both the high-resolution LORRI imager and the Ralph color imager will be used to look for clouds across the face of Pluto during its approach and departure from the planet.

An artist’s conception of clouds in Pluto’s atmosphere.

Credits: JHUAPL

“We’re looking for clouds in our images using a number of techniques,” said science team postdoc Kelsi Singer of the Southwest Research Institute, “If we find clouds, their presence will allow us to track the speeds and directions of Pluto’s winds.”

Contacts and sources:

Exercise and Artificial Gravity May Lessen Negative Effects of Weightlessness in Space

Astronauts on the International Space Station (ISS) have a number of exercise options, including a mechanical bicycle bolted to the floor, a weightlifting machine strapped to the wall, and a strap-down treadmill. They spend a significant portion of each day working out to ward off the long-term effects of weightlessness, but many still suffer bone loss, muscle atrophy, and issues with balance and their cardiovascular systems.

Swedish astronaut Christer Fuglesang tries out the new centrifuge while MIT professor Larry Young coaches him on.

Photo: Bill Litant/MIT AeroAstro

To counteract such debilitating effects, research groups around the world are investigating artificial gravity — the notion that astronauts, exposed to strong centrifugal forces, may experience the effects of gravity, even in space. Engineers have been building and testing human centrifuges — spinning platforms that, at high speeds, generate G-forces strong enough to mimic gravity. An astronaut, riding in a centrifuge, would presumably feel gravity’s reinforcing effects.

Now engineers at MIT have built a compact human centrifuge with an exercise component: a cycle ergometer that a person can pedal as the centrifuge spins. The centrifuge was sized to just fit inside a module of the ISS. After testing the setup on healthy participants, the team found the combination of exercise and artificial gravity could significantly lessen the effects of extended weightlessness in space — more so than exercise alone.

These illustrations depict how the researchers' new centrifuge could be used in space.

Courtesy of the researchers

Laurence Young, the Apollo Program Professor in MIT’s Department of Aeronautics and Astronautics, says artificial gravity would be a huge benefit for astronauts, particularly those embarking on long-duration space missions, such as a journey to Mars. The risks, he says, are uncertain, but potentially significant.

“With exploration-class missions, like Mars, where you’re gone for three years, you could run the risk of having astronauts not sufficiently conditioned to perform effectively, and also to not be in good health when they finally get to the surface of Mars,” says Young, a former NASA payload specialist. “You really don’t want to send a jellyfish to represent us on another planet.”

Young says a human centrifuge aboard a Mars-bound spacecraft would help keep an astronaut in shape over the many months it would take to get to the Red Planet. He and his colleagues, former graduate students Ana Diaz and Chris Trigg, have published results from their experiments in the journal Acta Astronautica.

Spinning up artificial gravity

The team’s compact centrifuge resembles a rotating metal cage with three main elements: a chair; a cycle ergometer, or the mechanical portion of a stationary bicycle; and a suite of sensors to measure cardiovascular variables such as blood pressure, heart rate, respiration rate, muscle activity, and foot forces.

The researchers conducted experiments to test human responses and exercise performance at varying levels of artificial gravity. The experiments involved 12 healthy subjects, who participated in three sessions, each consisting of a bicycling workout under one of three artificial gravity levels: zero G, in which the centrifuge did not rotate; 1 G, measured at the feet, in which the centrifuge spun at 28 revolutions per minute (rpm); and 1.4 G, also measured at the feet, at 32 rpm.

“When it spins around, we create centrifugal force, which depends on the angular velocity, or how fast we are rotating — the higher the angular velocity, the greater the artificial gravity,” Diaz says.

During each session, participants were asked to pedal for 15 minutes at three workout intensities, or levels of resistance, set by the cycle ergometer. The remaining 10 minutes involved spinning up and slowing down the centrifuge.

Beyond a “universal solution”

After each session, participants filled out a survey to gauge symptoms such as motion sickness and light-headedness. Overall, Diaz found that participants tolerated the experiments well, suffering little motion sickness even while spinning at relatively high velocities. Participants only reported feelings of discomfort while initially speeding up and slowing down.

“During the spinning process, participants were pushed against the chair due to the centrifugal force, making them sit comfortably, and facilitating their leg biomechanics for biking,” Diaz says.

As the researchers increased the centrifuge’s spin, raising its artificial gravity, participants used correspondingly more force to pedal — an unsurprising but encouraging result.

“That tells us that if we use artificial gravity, we’re able to get higher foot forces, and we know higher foot forces are good for bones, and help you generate more bone,” Diaz says. “Even if we expected this, we were able to quantify it and find a relationship between foot forces and artificial gravity.”

Similarly, as artificial gravity intensified, so did participants’ overall cardiovascular activity, a response that Diaz says may be beneficial over the long term.

Young says the study may begin to bridge two seemingly opposing camps: those who believe exercise alone will prevent bone loss, muscle atrophy, and other effects of extended weightlessness, and those who believe in artificial gravity as the solution.

“I think the principal finding here is supporting the conclusion that exercise alone is not a sufficient countermeasure,” Young says. “For the first time, we’re showing there’s a symbiosis when one combines the best aspects of exercise, and the best aspects of artificial gravity. So I feel this is an important demonstration.”

This research was funded in part by the National Space Biomedical Research Institute and a Skoltech/MIT seed grant.

Contacts and sources:
Abby Abazorius 
Jennifer Chu 
MIT News Office

Cosmic Fireworks Expected from Rare Stellar Encounter In 2018 - Video

Astronomers are gearing up for high-energy fireworks coming in early 2018, when a stellar remnant the size of a city meets one of the brightest stars in our galaxy. The cosmic light show will occur when a pulsar discovered by NASA's Fermi Gamma-ray Space Telescope swings by its companion star. Scientists plan a global campaign to watch the event from radio wavelengths to the highest-energy gamma rays detectable.
Credit: NASA's Goddard Space Flight Center

Coming attraction: Astronomers are expecting high-energy explosions when pulsar J2032 swings around its massive companion star in early 2018. The pulsar will plunge through a disk of gas and dust surrounding the star, triggering cosmic fireworks. Scientists are planning a global campaign to watch the event across the spectrum, from radio waves to gamma rays.

Credits: NASA's Goddard Space Flight Center

The pulsar, known as J2032+4127 (J2032 for short), is the crushed core of a massive star that exploded as a supernova. It is a magnetized ball about 12 miles across, or about the size of Washington, weighing almost twice the sun's mass and spinning seven times a second. J2032's rapid spin and strong magnetic field together produce a lighthouse-like beam detectable when it sweeps our way. Astronomers find most pulsars through radio emissions, but Fermi's Large Area Telescope (LAT) finds them through pulses of gamma rays, the most energetic form of light.

J2032 was found in 2009 through a so-called blind search of LAT data. Using this technique, astronomers can find pulsars whose radio beams may not be pointed precisely in our direction and are therefore much harder to detect.

"Two dozen pulsars were discovered this way in the first year of LAT data alone, including J2032," said David Thompson, a Fermi deputy project scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "Nearly all of them would not have been found without Fermi."

Once they knew exactly where to look, radio astronomers also were able to detect J2032. A team at the Jodrell Bank Centre for Astrophysics at the University of Manchester in the U.K. kept tabs on the object from 2010 through 2014. And they noticed something odd.

"We detected strange variations in the rotation and the rate at which the rotation slows down, behavior we have not seen in any other isolated pulsar," said Andrew Lyne, professor of physics at the University of Manchester. "Ultimately, we realized these peculiarities were caused by motion around another star, making this the longest-period binary system containing a radio pulsar."

The massive star tugging on the pulsar is named MT91 213. Classified as a Be star, the companion is 15 times the mass of the sun and shines 10,000 times brighter. Be stars drive strong outflows, called stellar winds, and are embedded in large disks of gas and dust.

"When we discovered this pulsar in 2009, we noticed that it was in the same direction as this massive star in the constellation Cygnus, but our initial measurements did not give any evidence that either star was a member of a binary system," explained Paul Ray, an astrophysicist at the Naval Research Laboratory in Washington. "The only way to escape that conclusion was if the binary system had a very long orbital period, much longer than the longest known pulsar-massive star binary at the time, which seemed unlikely."

Following an elongated orbit lasting about 25 years, the pulsar passes closest to its partner once each circuit. Whipping around its companion in early 2018, the pulsar will plunge through the surrounding disk and trigger astrophysical fireworks. It will serve as a probe to help astronomers measure the massive star's gravity, magnetic field, stellar wind and disk properties.

Several features combine to make this an exceptional binary. Out of six similar systems where the massive star uses hydrogen as its central energy source, J2032's has the greatest combined mass, the longest orbital period, and, at a distance of about 5,000 light-years, is closest to Earth.

"This forewarning of the energetic fireworks expected at closest approach in three years' time allows us to prepare to study the system across the entire electromagnetic spectrum with the largest telescopes," added Ben Stappers, a professor of astrophysics at the University of Manchester.

Astronomers think the supernova explosion that created the pulsar also kicked it into its eccentric orbit, nearly tearing the binary apart in the process. A study of the system led by Lyne and including Ray and Stappers was published June 16 in the journal Monthly Notices of the Royal Astronomical Society.

Contacts and sources:
Lynn Chandler
NASA's Goddard Space Flight Center

Dark Matter Map Begins to Reveal the Universe's Early History - Video

Researchers from the National Astronomical Observatory of Japan (NAOJ), the University of Tokyo and other institutions have begun a wide-area survey of the distribution of dark matter in the universe using Hyper Suprime-Cam, a new wide-field camera installed on the Subaru Telescope in Hawai'i.

A 14 arc minute by 9.5 arc minute section of a Hyper Suprime-Cam image, with contour lines showing the dark matter distribution.

Credit: NAOJ/HSC Project

Initial results from observations covering an area of 2.3 square degrees on the sky toward the constellation Cancer revealed nine large concentrations of dark matter, each the mass of a galaxy cluster. Surveying how dark matter is distributed and how the distribution changes over time is essential to understanding the role of dark energy that controls the expansion of the universe.

These first results demonstrate that astronomers now have the techniques and tools to understand dark energy. The next step is for the research team to expand the survey to cover a thousand square degrees on the sky, and thereby unravel the mystery of dark energy and the expansion of the universe.

Credit: Subaru Telescope NAOJe

Mapping dark matter over a wide region is key to understanding the properties of dark energy, which controls the expansion of the universe. These early results demonstrate that with current research techniques and Hyper Suprime-Cam, the team is now ready to explore how the distribution of dark matter in the universe has changed over time, unravel the mystery of dark energy, and explore the universe?s expansion history with great detail.

The data show a clear excess of dark matter concentrations over the current best theoretical model. Right: A schematic showing the dark matter concentrations discovered in the Hyper Suprime-Cam data. Left: A schematic showing predictions from current theoretical models.
Credit: NAOJ/HSC Project

Hyper Suprime-Cam lead developer, Dr. Satoshi Miyazaki, from the National Astronomical Observatory of Japan?s Advanced Technology Center and leader of the research team, praised the ability of the HSC for this work. "Now we know we have the both a technique and a tool for understanding dark energy. We are ready to use Hyper Suprime-Cam to create a 1000 square degree dark matter map that will reveal the expansion history of the universe with precise detail."

Using Weak Lensing by Dark Matter to Study Dark Energy's Effects:

Ever since 1929, when astronomer Edwin Hubble discovered that the universe is expanding, astronomers used a working model that had the rate of expansion slowing down over time. Gravitational attraction, until recently the only known force acting between galaxies, works against expansion. However, in the 1990s, studies of distant supernovae showed that the universe is expanding faster today than it was in the past. This discovery required a dramatic shift in our understanding of physics: either there?s some kind of "dark energy" with a repulsive force that forces galaxies apart, or the physics of gravity needs some fundamental revision (Note 1).

To unravel the mystery of the universe?s accelerating expansion, it is helpful to look at the relationship between the rate expansion of the universe and the rate at which astronomical objects form. For example, if the universe is expanding quickly, it will take longer for matter to coalesce and form galaxies. 

Conversely, if the universe is expanding slowly, it is easier for structures like galaxies to form. In effect, there?s a direct link between the history of structure formation in the universe, and the history of the universe's expansion. The challenge in confirming the existence of dark matter and its effect on expansion is that most of the matter in the universe is dark and does not emit light. It cannot be detected directly by telescopes, which are light-collecting machines.

One technique that can overcome this challenge is the detection and analysis of "weak lensing". A concentration of dark matter acts as a lens that bends light coming from even more distant objects. By analyzing how that background light is bent and how the lensing distorts the shapes of the background objects, it?s possible to determine how dark matter is distributed in the foreground. T

his analysis of dark matter and its effects lets astronomers determine how it has assembled over time. The assembly history of dark matter can be related to the expansion history of the universe, and should reveal some of the physical properties of dark energy, its strength and how it has changed over time.

To get a sufficient amount of data, astronomers need to observe galaxies more than a billion light-years away, across an area greater than a thousand square degrees (about one fortieth of the entire sky). The combination of the Subaru telescope, with its 8.2-meter diameter aperture, and Suprime-Cam, Hyper Suprime-Cam?s predecessor, with a field of view of a tenth of a square degree (comparable to the size of the Moon), has been one of the most successful tools in the search of faint distant objects over a wide area of sky.

However, even for this powerful combo, surveying a thousand degrees of sky at the necessary depth isn not realistic. "This is why we spent 10 years to develop Hyper Suprime-Cam, a camera with the same of better image quality as Suprime-Cam, but with a field of view over seven times larger," said Dr. Satoshi Miyazaki.

Hyper Suprime-Cam was installed on the Subaru Telescope in 2012. Following test observations, it was made available for open use by the astronomy community in March 2014. A "strategic" observing program, consisting of more than 300 nights of observing over five years is also underway. The camera, with 870 million pixels, delivers images that cover an area of sky as large as nine full moons in a single exposure, with extremely little distortion, at a fine resolution of seven thousandths of a degree (0.5 arc seconds).

Researchers from NAOJ, the University of Tokyo, and collaborators analyzed test data from Hyper Suprime-Cam?s commissioning to see how well it could map dark matter using the weak lensing technique. The data from a two-hour exposure covering 2.3 square degrees revealed crisp images of numerous galaxies. By measuring their individual shapes, the team created a map of the dark matter hiding in the foreground. 

The result was the discovery of nine clumps of dark matter, each weighing as much a galaxy cluster. The reliability of the weak lensing analysis, and the resulting dark matter maps, have been confirmed by observations with other telescopes that show actual galaxy clusters corresponding to the dark matter clumps discovered by Hyper Suprime-Cam. They utilized the archived Deep Lens Survey (PI: Tony Tyson, LSST Chief Scientist) data for the optical cluster identification.

The number of galaxy clusters by Hyper Suprime-Cam exceeds predictions from current models of the universe?s early history. As the research team expands the dark matter map to their goal of a thousand square degrees, the data should reveal whether this excess is real or just a statistical fluke. If the excess is real, it suggests that there wasn?t as much dark energy as expected in the past, which allows the universe to expand gently and stars and galaxies to form quickly.

Using weak lensing to map dark matter map is a way to discover astronomical objects using their mass, to learn that something exists and how much it weighs at the same time. It gives a direct measurement of mass that is typically unavailable when using other methods of discovery (Note 2). Therefore, mass maps of dark matter are an essential tool for understanding the expansion history of the universe precisely and accurately.


1 The 2011 Nobel Prize in Physics was awarded "for the discovery of the accelerating expansion of the universe through observations of distant supernovae" with one half going to Saul Perlmutter (Lawrence Berkeley National Lab & the University of California, Berkeley) and the other half going jointly to Brian P. Schmidt (Australian National University) and Adam G. Riess (Johns Hopkins University & Space Science Institute).

2 Light, electromagnetic radiation of all wavelengths including, radio, visible light, and x-rays, is the standard search tool for astronomical objects. In general, there is no simple relationship between the amount of light an object emits and its mass. The distortion of light observed in weak lensing is a direct measure of mass, and is therefore a much more reliable tool for determining the distribution of mass in the universe.

Contacts and sources: 
Satoshi Miyazaki
National Astronomical Observatory of Japan

Saeko S. Hayashi,
Subaru Telescope, National Astronomical Observatory of Japan 

These are the first scientific results from Hyper Suprime-Cam and were accepted for publication in the July 1, 2015 edition of the Astrophysical Journal. (Miyazaki et al. 2015, ApJ 807, 22, "Properties of Weak Lensing Clusters Detected on Hyper Suprime-Cam 2.3 Square Degree Field".) This research has received Grants-in-Aid for Scientific Research (18072003 and 26800093) and World Premier International Research Center Initiative support through the Japanese Society for the Promotion of Science.