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Wednesday, July 16, 2008

Who's the brightest star of all?

The Peony nebula (reddish cloud around white circle) near the galactic centre is home to a star that rivals the stellar powerhouse Eta Carinae in brightness (Image: NASA/JPL-Caltech/Potsdam Univ)
The Peony nebula (reddish cloud around white circle) near the galactic centre is home to a star that rivals the stellar powerhouse Eta Carinae in brightness (Image: NASA/JPL-Caltech/Potsdam Univ)

There's a new contender for the title of the Milky Way's brightest star.

The star had been discovered previously in the Peony nebula near the galaxy's dusty centre. But infrared observations taken from the ground and with NASA's Spitzer Space Telescope have pierced the dust to reveal just how bright the star is.

It boasts a wattage of about 3.2 million Suns. That is close to the output of Eta Carinae, the current record holder, which shines with the light of about 4.7 million Suns. However, measuring stellar brightness is not an exact science, and the stars may actually radiate similar amounts of light.

"As we get better measurements, these things change around a bit," says Michelle Thaller at NASA's Jet Propulsion Laboratory in California, who was not involved in the study.

It's possible that the galaxy's brightest star has not even been discovered yet. "There are probably other stars just as bright if not brighter in our galaxy that remain hidden from view," says team leader Lidia Oskinova of Potsdam University in Germany.

New stars

Both Eta Carinae and the Peony nebula star are evolved blue giants known as "Wolf-Rayet" stars, which have masses of 100 to 200 Suns. Either could self-destruct as a supernova at any moment.

The Peony nebula star lies about 26,000 light years away and Eta Carinae about 7500 light years away. "For all we know, they may have already blown themselves up and we're just waiting for the light to get to us to tell us that," Thaller told New Scientist.

For Thaller and other astronomers, knowing which blue giant is the brightest is less important than understanding what role the massive stars play in galactic evolution.

"These are real drivers of a galaxy's life cycle," Thaller says. "When these things go off, they will probably kick off a new generation of stars."

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Voyager 2 unravels mysteries at solar system's edge

Voyager2_2 What a long, strange, enlightening trip it's been for NASA's Voyager 2. Oh solar system, we thought we knew you, but Voyager 2's findings make us revise our visions. (Yes, we're squashed.)

Voyager 2 has been in space for 30 years. It has sent back data that show exotic particles from outside the solar system dominate the outer edge of our solar system. That means it's much more complex out there than we thought.

Last August, Voyager 2 reached the termination shock (83 times farther than the distance between Earth and the sun). That's where the solar wind from our sun slows to subsonic speeds and interacts with and affects the interstellar gas. The spacecraft's mission is to travel toward the outer limits of the heliosphere. That's a bubble (see photo) in space created by the solar wind's multi-directional flow.

Surprisingly, the temperatures at the termination shock are lower than our theories posited. There are also high-velocity particles out there that our models didn't foresee.

"This was totally unexpected," says Stamatios Krimigis of The Johns Hopkins University Applied Physics Laboratory (APL) and principal investigator for Voyager 2's Low-Energy Charged Particles (LECP) instrument, which detected the very highest energy particles. "The environment is totally unlike what the models predicted."

We thought that when the solar wind suddenly slows down at the termination shock, from 217 miles per second to 81 miles per second, the huge amount of energy released heated up the ions and electrons in the solar wind. Not so.

"The temperature was too low to account for the energy loss," says APL's Rob Decker. "We had to ask, where was that energy going?"

They now think most of that energy accelerates particles -- dubbed "pick-up ions" because they were picked up by the solar wind -- from outside the solar system that migrated into the heliosphere.

The heliosheath, beyond the termination shock, is where the slowed solar wind shifts from the interstellar medium and shapes our bullet-like heliosphere.

"Once they are beyond the termination shock, the pick-up ions affect how that medium behaves," says Decker. "They are carrying a lot of energy and therefore play a large role in the dynamics of the flowing plasma, modifying the heliosheath's width and its magnetic field structure, for example. But that's something we're still trying to understand."

Voyager 1 and Voyager 2 crossed the termination shock 10 billion miles apart. Voyager 1 was above and Voyager 2 was below. Researchers thought the environments would be similar. Again, not so. Voyager 2 "sees" much more variability than Voyager 1.

By Jess Zielinski
Photo: NASA/JPL

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It's All Decked Out. Give It Somewhere to Go.

Consider the International Space Station, that marvel of incremental engineering. It has close to 15,000 cubic feet of livable space; 10 modules, or living and working areas; a Canadian robot arm that can repair the station from outside; and the capacity to keep five astronauts (including the occasional wealthy rubbernecking space tourist) in good health for long periods. It has gleaming, underused laboratories; its bathroom is fully repaired; and its exercycle is ready for vigorous mandatory workouts.

The only problem with this $156 billion manifestation of human genius -- a project as large as a football field that has been called the single most expensive thing ever built -- is that it's still going nowhere at a very high rate of speed. And as a scientific research platform, it still has virtually no purpose and is accomplishing nothing.

I try not to write this cavalierly. But if the station's goal is to conduct yet more research into the effects of zero gravity on human beings, well, there's more than enough of that already salted away in Russian archives, based on the many years of weightlessness that cosmonauts heroically logged in a series of space stations throughout the 1970s, '80s and '90s. By now, ISS crews have also spent serious time in zero gravity. We know exactly what weightlessness does and how to counter some of its atrophying effects. (Cue shot of exercycle.)

And if the station's purpose is to act as a "stepping stone" to places beyond -- well, that metaphor, most recently used by NASA Administrator Michael Griffin is pure propaganda. As any student of celestial mechanics can tell you, if you want to go somewhere in space, the best policy is to go directly there and not stop along the way, because stopping is a waste of precious fuel, time and treasure. Which is a pretty good description of the ISS, parked as it is in constant low Earth orbit.

This is no doubt why, after the horrifying disintegration of the space shuttle Columbia in 2003, the Bush administration belatedly recognized that, if we're going to spend all that money on manned spaceflight, we should justify the risks by actually sending our astronauts somewhere. So NASA is now developing a new generation of rockets and manned spacecraft. By 2020, the Constellation program is supposed to take astronauts beyond low Earth orbit for the first time since Apollo 17 returned from the moon in 1972. Yes, that'll be almost 50 years. Where will they go? To the moon -- the only place humans have already visited.

Which leads us right back to the expensively orbiting ISS. It hasn't a fig-leaf's role left. The moon is the new "stepping stone," with Mars bruited as a next destination. Although NASA officials will never quite say so, their current attitude seems to be that the station is essentially a high-maintenance distraction, even a mistake. Their plan is to finish assembling the thing ASAP and hand the keys over to the Russians, Canadians, Europeans and Japanese, with minimal continuing U.S. involvement. This should happen by the shuttle's mandatory retirement in 2010. Meanwhile, we're still writing a lot of high-denomination checks and preparing the two remaining shuttles for risky flights to finish something we then plan to be largely rid of. This seems absurd. I have an alternative proposal:

Send the ISS somewhere.

The ISS, you see, is already an interplanetary spacecraft -- at least potentially. It's missing a drive system and a steerage module, but those are technicalities. Although it's ungainly in appearance, it's designed to be boosted periodically to a higher altitude by a shuttle, a Russian Soyuz or one of the upcoming new Constellation program Orion spacecraft. It could fairly easily be retrofitted for operations beyond low-Earth orbit. In principle, we could fly it almost anywhere within the inner solar system -- to any place where it could still receive enough solar power to keep all its systems running.

It's easy to predict what skeptics both inside and outside NASA will say to this idea. They'll point out that the new Constellation program is already supposed to have at least the beginnings of interplanetary ability. They'll say that the ISS needs to be resupplied too frequently for long missions. They'll worry about the amount of propellant needed to push the ISS's 1,040,000 pounds anywhere -- not to mention bringing them all back.

There are good answers to all these objections. We'll still need the new Constellation Ares boosters and Orion capsules -- fortuitously, they can easily be adapted to a scenario in which the ISS becomes the living- area and lab core of an interplanetary spacecraft. The Ares V heavy-lift booster could easily send aloft the additional supplies and storage and drive modules necessary to make the ISS truly deep-space-worthy.

The Orion crew exploration module is designed to be ISS-compatible. It could serve as a guidance system and also use its own rocket engine to help boost and orient the interplanetary ISS. After remaining dormant for much of the one-year journey to, say, Mars, it could then be available to conduct independent operations while the ISS core orbited the Red Planet, or to investigate an asteroid near Earth, for instance.

But, the skeptics will say, the new Orion capsule's engines wouldn't be nearly enough; a spacecraft as large as the ISS would need its own drive system. Here, too, we're in surprisingly good shape. The ISS is already in space; the amount of thrust it needs to go farther is a lot less than you might think. Moreover, a drive system doesn't have to be based on chemical rockets. Over the past two decades, both the U.S. and Japanese programs have conducted highly successful tests in space of ion-drive systems. Unlike the necessarily impatient rockets we use to escape Earth's gravity and reach orbit, these long-duration, low-thrust engines produce the kind of methodical acceleration (and deceleration) appropriate for travel once a spacecraft is already floating in zero gravity. They would be a perfect way to send the ISS on its way and bring it back to Earth again.

This leaves a lander. A lunar lander substantially larger than the spidery Apollo-era LEMs is currently on the drawing board. It's not nearly as far along in development as the Ares booster and Orion spacecraft components of the Constellation program -- which is a good thing. While I question the need to return to the moon in the first place, I wouldn't exclude it as a possible destination, so I think we should modify the lander's design to make it capable of touching down on either the moon or Mars and then returning to the ISS with samples for study in its laboratories. Such landers could also investigate the moon's poles, where we think water may be present, or one of the near-Earth asteroids -- which may have raw materials suitable for use by future generations of space explorers.

But, our skeptics will sputter, this will all cost far more money than the Constellation program. Who'll pay for it?

Actually, it will in effect save all the money we've already spent on the ISS. And the station is already an international project, with substantial financial and technological input from the Russians, Canadians, Europeans and Japanese. In recent years, the Chinese, who have developed their own human spaceflight capabilities, have made repeated overtures to NASA, hoping to be let in on the ISS project. They've been unceremoniously rebuffed by the Bush administration, but a new administration may be more welcoming. An interplanetary ISS -- the acronym now standing for International Space Ship -- would be a truly international endeavor, with expenses shared among all participating nations.

How likely is any of this to happen? Not very. A lot depends on the flexibility of a NASA that hasn't always been particularly welcoming to outside ideas. On the other hand, the agency also collaborates with outsiders all the time. So it's not impossible. The reason the ISS went from being a purely American, Reagan-era project ("Space Station Freedom") to one including the Russians and many other nations was a political decision by the Clinton administration. A similar political vision will be necessary here.

All the billions already spent on the space station would pay off -- spectacularly -- if this product of human ingenuity actually went somewhere and did something. But it would also serve as a compelling demonstration that we're one species, living on one planet, and that we're as capable of cooperating peacefully as we are at competing militaristically. Let's begin the process of turning the ISS from an Earth-orbiting caterpillar into an interplanetary butterfly.

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NASA engineers work on alternative moon rocket

By JAY REEVES, Associated Press Writer
HUNTSVILLE, Ala. - By day, the engineers work on NASA's new Ares moon rockets. By night, some go undercover to work on a competing design. These dissenting scientists and their backers insist they have created an alternative rocket that would be safer, cheaper and easier to build than the two Ares spacecraft that will replace the space shuttle.

They call their project Jupiter, and like Ares, it's a brainchild of workers at the Marshall Space Flight Center and other NASA facilities. The engineers involved are doing the work on their own time and mostly anonymously, with the help of retirees and other space enthusiasts.

A key Ares project manager dismisses their design as little more than a sketch on a napkin that won't work.

A spokesman for the competing effort, Ross Tierney, said concerned engineers at NASA and some contractors want a review of the Ares plans but can't speak out for fear of being demoted, transferred or fired.

The Jupiter design is being reviewed by a team of 57 volunteer engineers, from line engineers up to NASA middle managers, Tierney said. Those numbers are dwarfed by NASA's Ares workforce, which has thousands of government workers and contractors.

The head of the Ares office at Marshall said he can't rule out the possibility that some of his people are involved with the underground program.

"I don't know what people do on their own time," Steve Cook said in a recent interview with The Associated Press.

But Cook said he is familiar with the Jupiter project, and he's not impressed. NASA informally reviewed plans for the rocket last fall and determined the idea to be a flawed scheme based on shaky numbers.

"It's not feasible. We said, 'It doesn't work' and moved on,'" Cook said.

Meanwhile, he said, work on the Ares I rocket is so far along that the first test flight is less than a year away.

"We're down to the nuts and bolts ... on this rocket. This is not a napkin drawing," he said.

The debate reflects disagreement over the direction of U.S. spaceflight as NASA prepares to retire the shuttle in 2010. By 2015, the agency plans to begin orbital flights with Ares I and a companion heavy-lift cargo rocket, Ares V. Officials hope to return astronauts to the moon by 2020.

Astronauts will ride into orbit in a capsule aboard the Ares I, which will have a modified shuttle booster rocket at its core. They will dock with a lunar stage that was carried aloft separately by an Ares V rocket and head to the moon.

The Jupiter design would also require two separate launches to get to the moon, but its rockets would both rely on a shuttle external tank at their center. Some of the design concepts go back to proposals floated at Marshall in the early 1980s. Others date to the early '90s, when Marshall worked on a new rocket system that never flew.

Besides being a simpler, more powerful system, backers say, the Jupiter rockets would save NASA $19 billion in development costs and another $16 billion in operating costs over two decades.

The Government Accountability Office last year raised questions about the cost of NASA's current plan for returning to the moon, which a report estimated at $230 billion over 20 years. NASA said it already has spent about $7 billion on Ares.

Steve Metschan, an engineer and former NASA contractor who supports the Jupiter team, said the upcoming presidential election could change NASA's plan. He accused NASA of suppressing information that shows Jupiter would perform better than Ares.

"Our concern is that by the time everyone figures this out, we will have destroyed our heavy-lift system," said Metschan, of Seattle. "At the end of the day, all we're asking for is an independent review of all this stuff."

Cook said all the estimates on Jupiter were preliminary, and he denied critics' claims that NASA did a full-fledged study of the Jupiter rocket or the engineers' alternate moon-mission program, which they call Direct 2.0.

NASA has looked at "all sorts" of proposed designs, he said, and none was as powerful or safe as Ares.

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Pathologists Believe They Have Pinpointed Achilles Heel Of HIV


Scientists in UT Houston laboratory of Sudhir Paul, Ph.D., may have uncovered a chink the armor of the deadly HIV virus. Pictured from left to right are: Paul, Yasuhiro Nishiyama, Ph.D., and Stephanie Planque. (Credit: Image courtesy of University of Texas Health Science Center at Houston)

Human Immunodeficiency Virus (HIV) researchers at The University of Texas Medical School at Houston believe they have uncovered the Achilles heel in the armor of the virus that continues to kill millions.

The weak spot is hidden in the HIV envelope protein gp120. This protein is essential for HIV attachment to host cells, which initiate infection and eventually lead to Acquired Immunodeficiency Syndrome or AIDS. Normally the body’s immune defenses can ward off viruses by making proteins called antibodies that bind the virus. However, HIV is a constantly changing and mutating virus, and the antibodies produced after infection do not control disease progression to AIDS. For the same reason, no HIV preventative vaccine that stimulates production of protective antibodies is available.

The Achilles heel, a tiny stretch of amino acids numbered 421-433 on gp120, is now under study as a target for therapeutic intervention. Sudhir Paul, Ph.D., pathology professor in the UT Medical School, said, “Unlike the changeable regions of its envelope, HIV needs at least one region that must remain constant to attach to cells. If this region changes, HIV cannot infect cells. Equally important, HIV does not want this constant region to provoke the body’s defense system. So, HIV uses the same constant cellular attachment site to silence B lymphocytes - the antibody producing cells. The result is that the body is fooled into making abundant antibodies to the changeable regions of HIV but not to its cellular attachment site. Immunologists call such regions superantigens. HIV’s cleverness is unmatched. No other virus uses this trick to evade the body’s defenses.”

Paul is the senior author on a paper about this theory in a June issue of the journal Autoimmunity Reviews. Additional data supporting the theory are to be presented at the XVII International AIDS Conference Aug. 3-8 in Mexico City in two studies titled “Survivors of HIV infection produce potent, broadly neutralizing IgAs directed to the superantigenic region of the gp120 CD4 binding site” and “Prospective clinical utility and evolutionary implication of broadly neutralizing antibody fragments to HIV gp120 superantigenic epitope.”

First reported in the early 1980s, HIV has spread across the world, particularly in developing countries. In 2007, 33 million people were living with AIDS, according to a report by the World Health Organization and the United Nations.

Paul’s group has engineered antibodies with enzymatic activity, also known as abzymes, which can attack the Achilles heel of the virus in a precise way. “The abzymes recognize essentially all of the diverse HIV forms found across the world. This solves the problem of HIV changeability. The next step is to confirm our theory in human clinical trials," Paul said.

Unlike regular antibodies, abzymes degrade the virus permanently. A single abzyme molecule inactivates thousands of virus particles. Regular antibodies inactivate only one virus particle, and their anti-viral HIV effect is weaker.

“The work of Dr. Paul’s group is highly innovative. They have identified antibodies that, instead of passively binding to the target molecule, are able to fragment it and destroy its function. Their recent work indicates that naturally occurring catalytic antibodies, particularly those of the IgA subtype, may be useful in the treatment and prevention of HIV infection,” said Steven J. Norris, Ph.D., holder of the Robert Greer Professorship in the Biomedical Sciences and vice chair for research in the Department of Pathology and Laboratory Medicine at the UT Medical School at Houston.

The abzymes are derived from HIV negative people with the autoimmune disease lupus and a small number of HIV positive people who do not require treatment and do not get AIDS. Stephanie Planque, lead author and UT Medical School at Houston graduate student, said, “We discovered that disturbed immunological events in lupus patients can generate abzymes to the Achilles heel of HIV. The human genome has accumulated over millions of years of evolution a lot of viral fragments called endogenous retroviral sequences. These endogenous retroviral sequences are overproduced in people with lupus, and an immune response to such a sequence that resembles the Achilles heel can explain the production of abzymes in lupus. A small minority of HIV positive people also start producing the abzymes after decades of the infection. The immune system in some people can cope with HIV after all.”

Carl Hanson, Ph.D., who heads the Retrovirus Diagnostic Section of the Viral and Rickettsial Disease Laboratory of the California Department of Public Health, has shown that the abzymes neutralize infection of human blood cells by diverse strains of HIV from various parts of the world. Human blood cells are the only cells that HIV infects.

“This is an entirely new finding. It is a novel antibody that appears to be very effective in killing the HIV virus. The main question now is if this can be applied to developing vaccine and possibly used as a microbicide to prevent sexual transmission,” said David C. Montefiori, Ph.D., director of the Laboratory for AIDS Vaccine Research & Development at Duke University Medical Center. The abzymes are now under development for HIV immunotherapy by infusion into blood. They could also be used to guard against sexual HIV transmission as topical vaginal or rectal formulations.

“HIV is an international priority because we have no defense against it,” Paul said. “Left unchecked, it will likely evolve into even more virulent forms. We have learned a lot from this research about how to induce the production of the protective abzymes on demand. This is the Holy Grail of HIV research -- development of a preventative HIV vaccine.”

Major contributors to the research from the UT Medical School include Yasuhiro Nishiyama, Ph.D., and Hiroaki Taguchi, Ph.D., both with the Department of Pathology and Laboratory Medicine, and Miguel Escobar, M.D., of the Department of Pediatrics. Maria Salas and Hanson, both with the Viral and Rickettsial Disease Laboratory, contributed.

The research was funded by the National Institutes of Health and the Texas Higher Education Coordinating Board.

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Scientists discover 'world's first bird' that lived 235million years ago

Palaeontologists have unveiled an extraordinary prehistoric 'flying' reptile which lived 235 million years ago.

The kuehneosaurs glided through the subtropical forests of Europe using scaly 'wings' that could carry it distances of more than 30ft.

Experts say the lizard-like reptile, which grew up to 2ft long, used extensions of their ribs to form large gliding surfaces on the sides of their body.

The scientific community is united in the belief that birds descended from reptiles 50 million years later making the kuehneosaurs the world's first 'bird'.

The kuehneosaurs glided through forests 385million years ago

The long-extinct species was first unearthed in the Britain by Archaeologists in the 1950s, but until now their aerodynamic capability had not been studied.

Their rudimentary 'wings' were always assumed to be some form of flying adaption, but scientists at the time lacked the necessary technology to test the theory.

But earlier this year, experts from Bristol University investigated both types of kuehneosaurs found in the UK - kuehneosuchus and kuehneosaurus - for the first time.

The team built lifesize models of the creatures and used techniques usually employed to test prototype aircraft - including a wind tunnel - to discover their amazing flying ability.

Their pioneering findings, published this week by the Paleontological Association, have turned the history of winged flight on its head.

Today German palaeobiologist Koen Stein, who led the study, said: 'We didn't think kuehneosaurs would have been very efficient in the air. But all the work up to now had been speculation.

'So we decided to build models and test them in the wind tunnel in the Department of Aerospace Engineering at Bristol University.

'Surprisingly, we found that kuehneosuchus was aerodynamically very stable. Jumping from a tree, it could easily have crossed 9m (29ft) before landing on the ground.'

The species, which inhabited the warm late Triassic period from 235 to 200 million years ago, was first discovered in the UK inside an ancient cave system near Bristol.

Both types of kuehneosaurs lived 80 million years before the largest dinosaurs of the Jurassic period, and 50 million years before the earliest known bird, archaeopteryx, which lived in what is now southern Germany.

Mr Stein and his colleagues used a number of different materials to reconstruct the creatures' scaly wings, which they then tested using specialist aerodynamic equipment.

Aerospace engineers suspended the models in a wind tunnel and passed a jet of hot air over the models' bodies.

This gave experts a detailed idea about the air flow over their wings, and the distance they would have glided from tree-top to tree-top in search of food and to escape larger predators. But Mr Stein admitted the task wasn't always straightforward.

He added: 'We also built webbed hands and feet, and had an extra skin membrane between the legs on the models, but these made the flight of the animals unstable, suggesting they probably did not have such features.'

Mr Stein, who now works at the prestigious Institute of Palaeontology at Bonn in Germany, carried out the research with Colin Palmer, Pamela Gill and Michael Benton from Bristol University's Department of Earth Sciences.

Department head Professor Michael Benton said: 'Palaeontologists are keen to understand how all the amazing animals of the past operated, and by collaborating with aerospace engineers we can be sure that model-making and calculations are more realistic.'

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Shit Happens…


Brain at work during a good night's sleep

After a particularly creative night's sleep, Paul McCartney rushed to the piano at his girlfriend Jane Asher's house to scribble down a tune he had heard in a dream. That song, Yesterday, would become a Beatles classic.

Few can claim their slumbering hours are as productive or as lucrative, but scientists have found evidence that "sleeping on the problem" does work. By scanning the brains of volunteers, they found that a good night's shut-eye seems to stimulate new brain connections that promote learning by turning a weak memory into a stronger one.

Dr Sophie Schwartz, from the University of Geneva, gave volunteers the task of remembering unknown faces or using a joystick to follow a moving dot on a computer screen. Some were then allowed to sleep while others were not. They repeated the same tasks the next day while having their brains scanned. The results showed that "a period of sleep following a new experience can consolidate and improve subsequent effects of learning from the experience", says Schwartz.

The brain changes were highly localised and relevant to the task the volunteer had been set. For example, the researchers observed changes in the face-responsive fusiform cortex in the unknown faces task. Schwartz will report her study today at the Forum of European Neuroscience meeting in Geneva.

In future, she wants to find out whether by understanding the brain changes involved, the learning effect can be boosted, and assess how sleep disorders affect emotional and cognitive functioning.

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Freeing light shines promise on energy-efficient lighting

ANN ARBOR, Mich.—The latest bright idea in energy-efficient lighting for homes and offices uses big science in nano-small packages to dim the future Edison's light bulb.

In the August issue of Nature Photonics, available online, scientists at the University of Michigan and Princeton University announce a discovery that pushes more appealing white light from organic light-emitting devices.

More white light is the holy grail of the next generation of lighting. The innovation in the paper "Enhanced Light Out-Coupling of Organic Light-Emitting Devices Using Embedded Low-Index Grids" describes a way to deliver significantly more bright light from a watt than incandescent bulbs.

"Our demonstration here shows that OLEDs are a very exciting technology for use in interior illumination," said Stephen Forrest, U-M professor of electrical engineering and physics and vice president for research. "We hope that white emitting OLEDs will play a major role in the world of energy conservation."

Forrest and co-author Yuri Sun, visiting U-M from Princeton University, have wrestled with a classic problem in the new generation of lighting called white organic light-emitting devices, or WOLED: Freeing the light generated, but mostly trapped, inside the device.

A lighting primer: Incandescent light bulbs give off light as a by-product of heat, The light is appealing, but inefficient, putting out 15 lumens of light for every watt or electricity.

The best fluorescent tube lights put out some 90 lumens of light per watt, but the light can be harsh, the fixtures are expensive, and the tubes lose their efficiency with age. And they rely on many environmentally unfriendly substances such as mercury.

WOLEDs show promise of providing a light that's much easier to manipulate, while being long lasting and able to provide in different shapes, from panels to bulbs and more. WOLEDs generate white light by using electricity to send an electron into nanometer thick layers of organic materials that serve as semiconductors. These carbon-based materials are dyes, the ones used in photographic prints and car paint, so they are very inexpensive, and can be put on plastic sheets or metal foils, further reducing costs.

The excited electron in these layers casts bright white light. The bad news, Forrest said, has been that some 60 percent of it is trapped inside the layers, much the way light under water reflects back into the pool, making the water surface seem like a mirror when viewed from underneath.

The Nature Photonics paper describes a tandem system of organic grids and micro lenses that guide the light out of the thin layers and into the air. The grids refract the trapped light, bouncing it into a layer of dome-shaped lenses that then pull the light out.

This process—all of which is packed into a lighting sandwich roughly the thickness of a sheet of paper—was shown to emit approximately 70 lumens from a single watt of power.

More light out means getting more bang for the electricity buck, a crucial question since 22 percent of the U.S. electricity consumption is lighting.

"If you can change the light efficiency by just a few percentage points, there's a few less coal plants you'll need," Forrest said.

Reducing the amount of coal-generated electricity and finding more efficient ways to power appliances and lighting is one of the focuses of U-M's Michigan Memorial Phoenix Energy Institute, and the WOLED work is one example of how science can open new doors in conservation, said Gary Was, institute director.

"That energy efficient lighting can be made from the same materials as car paint and that they can be made in such thin, formable sheets boggles the mind," Was said. "This is one of many exciting creations that research is giving us in the pursuit of energy efficiency. This is also the kind of innovation that is required in the drive for energy sustainability.

Forrest said WOLED work isn't done yet. The fun part, he said, is that WOLEDs can be framed in different forms.

"Plugging into a wall at low voltage, putting it on a flexible metal foil, or on plastic that won't break when you drop it," Forrest said. "This is what makes it so fun because it's such a unique lighting source."

The research was funded by the U.S. Department of Energy through a subcontract from the University of Southern California and by Universal Display Corp.

Forrest is part of the Michigan Memorial Phoenix Energy Institute, which develops, coordinates and promotes multidisciplinary energy research and education at U-M. He also is on the scientific advisory board of Universal Display Corp.

The next challenge, he said, is to reduce the cost, which currently is too high to be commercially competitive.

"You have to be able to do this dirt cheap, Forrest said. "People don't spend much for their light bulbs."

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First U.S. Town Powered Completely By Wind

By Andrea Thompson, Senior Writer

Rock Port, Mo., has an unusual crop: wind turbines.

The four turbines that supply electricity to the small town of 1,300 residents make it the first community in the United States to operate solely on wind power.

"That's something to be very proud of, especially in a rural area like this — that we're doing our part for the environment," said Jim Crawford, a natural resource engineer at the University of Missouri Extension in Columbia.

A map published by the U.S. Department of Energy indicates that northwest Missouri has the state's highest concentrations of wind resources and contains a number of locations that are potentially suitable for utility-scale wind development. The four turbines that power Rock Port are part of a larger set of 75 turbines across three counties that are used to harvest the power of wind.

"We're farming the wind, which is something that we have up here," Crawford said. "The payback on a per-acre basis is generally quite good when compared to a lot of other crops, and it's as simple as getting a cup of coffee and watching the blades spin."

And the turbines have another benefit besides produces clean energy: MU Extension specialists said that the Missouri wind farms will bring in more than $1.1 million annually in county real estate taxes, to be paid by Wind Capital Group, a wind energy developer based in St. Louis.

"This is a unique situation because in rural areas it is quite uncommon to have this increase in taxation revenues," said Jerry Baker, and MU Extension community development specialist.

Landowners can also benefit by leasing part of their property for wind turbines.

The turbines will also provide savings to rural electric companies and will provide electric service for at least 20 years, the anticipated lifetime of the turbines.

"Anybody who is currently using Rock Port utilities can expect no increase in rates for the next 15 to 20 years," Crawford said.

Baker added that the turbines could also attract tourists to the area.

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An Air Car You Could See in 2009: ZPM’s 106 MPG Compressed-Air Hybrid