- Saturn’s Hexagon May Be Solar System’s Coolest Mystery
- Geeky Math Equation Creates Beautiful 3-D World
- Wireless Brain-to-Computer Connection Synthesizes Speech
- That Crazy Spiral in the Sky? It Might Be Real
- Mediterranean Sea Saved by Monumental Flood
- The Psychology of Climate Change Denial
- Green Fuel-Cell Makeover for Future Power Plants
Posted: 09 Dec 2009 05:01 PM PST
The Cassini spacecraft has returned the best images yet of the strange hexagonal jet stream that flows around the northern pole of Saturn.
First discovered by the Voyager spacecraft in the early 1980s, the hexagon remains a beautiful mystery to astronomers, and one they've been waiting for another shot to see for almost three decades.
"The longevity of the hexagon makes this something special, given that weather on Earth lasts on the order of weeks," said Kunio Sayanagi, a Cassini project researcher at the California Institute of Technology, in a NASA release. "It's a mystery on par with the strange weather conditions that give rise to the long-lived Great Red Spot of Jupiter."
The hexagon circles Saturn at 77 degrees north and is wider than two Earths. Nearly everything about the weather pattern is baffling. First, it's unclear what causes the hexagon. Second, it's bizarre that the jet stream would make such sharp turns. Earth's atmospheric movements rarely display such geometric rigor.
Fifty-five images were stitched together to create a three-frame animation of the jet stream on the move (see below). The sharp black triangle jutting out of the central black circle is an artifact of the image processing.
Posted: 09 Dec 2009 05:00 PM PST
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The quest by a group of math geeks to create a three-dimensional analogue for the mesmerizing Mandelbrot fractal has ended in success.
They call it the Mandelbulb. The 3-D renderings were generated by applying an iterative algorithm to a sphere. The same calculation is applied over and over to the sphere's points in three dimensions. In spirit, that's similar to how the original 2-D Mandelbrot set generates its infinite and self-repeating complexity.
If you were ever mesmerized by the Mandelbrot screen saver, the following images are worth a look. Each photo is a zoom on one of these Mandelbulbs.
Posted: 09 Dec 2009 04:39 PM PST
A system that turns brain waves into FM radio signals and decodes them as sound is the first totally wireless brain-computer interface.
For now, 26-year-old Erik Ramsey, left almost entirely paralyzed by a horrific car accident 10 years ago, can only express vowel sounds with the system. That's less than can be accomplished with wired brain-computer interfaces. But it's still a promising step.
"All the groups working on BCIs are working toward wireless solutions. They are very superior," said Frank Guenther a Boston University cognitive scientist who helped developed Ramsey's system.
In the last decade, brain-computer interfaces, or BCIs, have made the jump from speculation to preliminary medical reality. Since Wired reported on quadriplegic BCI pioneer Matthew Nagle four years ago ("He's playing Pong with his thoughts alone"), the interfaces have been used to steer wheelchairs, send text messages and even to Tweet. They're so advanced that some researchers now worry about BCI ethics — what happens when healthy people get them? And they're concerned about the threat posed by hackers.
But as amazing as these early BCIs are, they're far from street-ready. Systems based on translating electrical signals captured by electrodes on patients' scalps are notoriously slow, capable of producing about one word a minute. If researchers put electrodes directly into patients' brains, the results are better — but that raises the possibility of dangerous infection. And from a purely practical point of view, wires just get in the way.
The implant system tested by Ramsey, as described in a paper published Wednesday in Public Library of Science ONE, was originally developed by Philip Kennedy, founder of Neural Signals, a company that specializes in BCIs. Several electrodes are implanted in Ramsey's cerebral cortex. Beneath the skin of his skull is an amplifier that gathers the electrodes' signals, and an FM transmitter that sends them to a nearby computer.
Using a neurological model constructed by Guenther, Ramsey's brain activity is mapped to corresponding mouth and jaw movements. Another program decodes the signals, and synthesizes them in the sound of a tinny, but human-like voice.
"The system produces the sound output in about 50 milliseconds. That's the time it takes for sound output to come from a motor cortex command in a normal individual," said Guenther.
The three wires in Ramsey's brain are only sufficient for making vowel sounds, said Guenther. But the researchers plan to add more electrodes, perhaps as many as 32. That would be more difficult to control, but would also allow Ramsey's thoughts to better mimic natural tongue and jaw movements, ultimately letting him form consonants as well.
For now, the computer that translates Ramsey's mental broadcasts is still in a laboratory. "But our goal is to have him transmit directly to a laptop," said Guenther.
Image: A schematic at left and CT scans at right of the wireless brain-computer interface. PLoS ONE.
Video: Visual and audio feedback is presented to Erik Ramsey. PLoS ONE.
Citation: "A Wireless Brain-Machine Interface for Real-Time Speech Synthesis." By Frank Frank H. Guenther, Jonathan S. Brumberg, E. Joseph Wright, Alfonso Nieto-Castanon, Jason A. Tourville, Mikhail Panko, Robert Law, Steven A. Siebert, Jess L. Bartels, Dinal S. Andreasen, Princewill Ehirim, Hui Mao, Philip R. Kennedy. Public Library of Science ONE, December 9, 2009.
Posted: 09 Dec 2009 02:09 PM PST
When we saw the pictures of the spiral in the Norwegian sky this morning, we immediately wrote it off as an impressively elaborate, funny-looking but well-executed hoax. You probably did too, even after reading Google Translated reports in Norwegian newspapers.
Now, SpaceWeather.com, a trusted source run by NASA science writer Tony Phillips, says the "evidence is mounting" that the sky show was real. And not just real, but the product of a Russian missile launch.
"A rocket motor spinning out of control could explain the spiral pattern, so this explanation seems plausible, although it has not yet been confirmed," Phillips wrote
A space animator even took the time to use a 3-D modeling program to show how the rocket motor could have made what seems a bizarrely regular shape. Although, the YouTube poster, unmannedspaceflight, made sure to note the rendering is "not an official answer."
Still, it seems just a little too perfect, right? Crazy looking lights, Russian missiles…. Let us know if you think it is real or not below.
Posted: 09 Dec 2009 12:40 PM PST
"In an instantaneous flash, the dry Mediterranean became a normal Mediterranean like we see it today," says lead author Daniel Garcia-Castellanos of Spain's Consejo Superior de Investigaciones Cientificas (CSIC) in Barcelona.
He and his colleagues calculate that at the height of the flood, water levels rose more than 10 meters and more than 40 centimeters of rock eroded away per day. The model also shows that 100 million cubic meters of water flowed through the channel per second, with water gushing at speeds of 100 kilometers an hour. Rather than a Niagara Falls-esque cascade from the Atlantic into the Mediterranean, the team's results imply a torrent several kilometers wide at a fairly gradual slope.
"It would be an exciting rafting place," Garcia-Castellanos says.
"As a hypothesis it makes sense, though it's still in early stages," says Sanjeev Gupta of Imperial College London. "There's lots more to be done to explore this idea. It's quite exciting, and I think it will get people interested in this topic."
Luckily, 5.3 million years ago water from the Atlantic Ocean found a way back in to the drying seabed through what is now the Strait of Gibraltar between Spain and Morocco. Geologists figured the resulting flood must have been impressive, but their estimates for how long it took have varied wildly, from 10 years to several thousand years.
"The record of the Mediterranean tells us that the transition from the dry, high salinity situation to the normal open water situation we have nowadays was very rapid," Garcia-Castellanos says. "But 'rapid' in geology could mean many tens of thousands of years."
Early models couldn't resolve the flood's timescale because they couldn't tell how the volume of water flowing through the Strait of Gibraltar changed with time, Garcia-Castellanos says. Earlier studies, including work by Gupta, had concluded that England was separated from Europe in a similar cataclysmic flood 450,000 years ago based on the U-shaped valley at the bottom of the Strait of Dover (SN: 7/21/07, p. 35). But because of how long ago the flood that filled the Mediterranean occurred, the geological record of erosion from rushing waters was thought long buried.
But Garcia-Castellanos and colleagues found it, thanks to plans for an underground train. Cores drilled in the seafloor as part of preparations for the Africa-Europe tunnel project, which hopes to run trains under the Strait of Gibraltar from Spain to Morocco, revealed a deep channel filled with loose sediment. Using the drilling data and previously collected seismic data, the researchers determined that the channel is 200 kilometers long, between 6 and 11 kilometers wide, and between 300 and 650 meters deep.
Other geologists who had noticed the channel thought it had formed through erosion by rainwater in a river network, like in the Rhone or Nile rivers. But while those river channels are V-shaped, the new data show that the Strait of Gibraltar channel has the distinctive U-shape of the seafloor beneath the Strait of Dover. This shape is a hint that the strait formed in a torrential flood.
Using equations derived from observations of mountain rivers, the team of researchers modeled how the flood might have progressed: The flood started gradually, but as the sill between the Atlantic and the dry Mediterranean wore down, the rate of water flowing and rock eroding increased exponentially. As more water flowed over the sill, more rock wore away, allowing ever more water to spill in.
The calculations show an upper limit of two years for how long it took to fill the Mediterranean. But Garcia-Castellanos says it could have been as short as a few months. The energy carried in such a flood is comparable to the heat transport along the Gulf Stream in a year, or 4 percent of the kinetic energy of the meteorite impact thought to have killed the dinosaurs.
"I was very satisfied with their explanation, I found it quite exciting," says Philip Gibbard of the University of Cambridge in England. "It's a really important development."
The flood would have had a dramatic effect on local ecosystems, and could even have affected the global climate. The model suggests that global sea level dropped 9.5 meters as a result of the flood. The team points out that a much smaller flood in North America 12,000 years ago has been linked to a worldwide cold snap, and suggests that the Mediterranean flood may have had similarly significant effects.
Images: 1) NASA. 2) Robert Pibernat.
Posted: 09 Dec 2009 10:29 AM PST
Even as the science of global warming gets stronger, fewer Americans believe it's real. In some ways, it's nearly as jarring a disconnect as enduring disbelief in evolution or carbon dating. And according to Kari Marie Norgaard, a Whitman University sociologist who's studied public attitudes towards climate science, we're in denial.
"Our response to disturbing information is very complex. We negotiate it. We don't just take it in and respond in a rational way," said Norgaard.
The Intergovernmental Panel on Climate Change declared in 2007 that greenhouse gases had reached levels not seen in 650,000 years, and were rising rapidly as a result of people burning fossil fuel. Because these gases trap the sun's heat, they would — depending on human energy habits — heat Earth by an average of between 1.5 and 7.2 degrees Fahrenheit by century's end. Even a midrange rise would likely disrupt the planet's climate, producing droughts and floods, acidified oceans, altered ecosystems and coastal cities drowned by rising seas.
"If there's no action before 2012, that's too late. What we do in the next two to three years will determine our future," said Rajendra Pachauri, the IPCC chairman, when the report was released. "This is the defining moment."
Studies published since then have only strengthened the IPCC's predictions, or suggested they underestimate future warming. But as world leaders gather in Copenhagen to discuss how to avoid catastrophic climate change, barely half the U.S. public thinks carbon pollution could warm Earth. That's 20 percent less than in 2007, and lower than at any point in the last 12 years. In a Pew Research Center poll, Americans ranked climate dead last out of 20 top issues, behind immigration and trade policy.
Wired.com talked to Norgaard about the divide between science and public opinion.
Wired.com: Why don't people seem to care?
Kari Norgaard: On the one hand, there have been extremely well-organized, well-funded climate-skeptic campaigns. Those are backed by Exxon Mobil in particular, and the same PR firms who helped the tobacco industry (.pdf) deny the link between cancer and smoking are involved with magnifying doubt around climate change.
That's extremely important, but my work has been in a different area. It's been about people who believe in science, who aren't out to question whether science has a place in society.
Wired.com: People who are coming at the issue in good faith, you mean. What's their response?
Norgaard: Climate change is disturbing. It's something we don't want to think about. So what we do in our everyday lives is create a world where it's not there, and keep it distant.
For relatively privileged people like myself, we don't have to see the impact in everyday life. I can read about different flood regimes in Bangladesh, or people in the Maldives losing their islands to sea level rise, or highways in Alaska that are altered as permafrost changes. But that's not my life. We have a vast capacity for this.
Wired.com: How is this bubble maintained?
Norgaard: In order to have a positive sense of self-identity and get through the day, we're constantly being selective of what we think about and pay attention to. To create a sense of a good, safe world for ourselves, we screen out all kinds of information, from where food comes from to how our clothes our made. When we talk with our friends, we talk about something pleasant.
Wired.com: How does this translate into skepticism about climate change?
Norgaard: It's a paradox. Awareness has increased. There's been a lot more information available. This is much more in our face. And this is where the psychological defense mechanisms are relevant, especially when coupled with the fact that other people, as we've lately seen with the e-mail attacks, are systematically trying to create the sense that there's doubt.
If I don't want to believe that climate change is true, that my lifestyle and high carbon emissions are causing devastation, then it's convenient to say that it doesn't.
Wired.com: Is that what this comes down to — not wanting to confront our own roles?
Norgaard: I think so. And the reason is that we don't have a clear sense of what we can do. Any community organizer knows that if you want people to respond to something, you need to tell them what to do, and make it seem do-able. Stanford University psychologist Jon Krosnick has studied this, and showed that people stop paying attention to climate change when they realize there's no easy solution. People judge as serious only those problems for which actions can be taken.
Another factor is that we no longer have a sense of permanence. Another psychologist, Robert Lifton, wrote about what the existence of atomic bombs did to our psyche. There was a sense that the world could end at any moment.
Global warming is the same in that it threatens the survival of our species. Psychologists tell us that it's very important to have a sense of the continuity of life. That's why we invest in big monuments and want our work to stand after we die and have our family name go on.
That sense of continuity is being ruptured. But climate change has an added aspect that is very important. The scientists who built nuclear bombs felt guilt about what they did. Now the guilt is real for the broader public.
Wired.com: So we don't want to believe climate change is happening, feel guilty that it is, and don't know what to do about it? So we pretend it's not a problem?
Norgaard: Yes, but I don't want to make it seem crass. Sometimes people who are very empathetic are less likely to help in certain situations, because they're so disturbed by it. The human capacity of empathy is really profound, and that's part of our weakness. If we were more callous, then we'd approach it in a more straightforward way. It may be a weakness of our capacity as sentient beings to cope with this problem.
"Cognitive and Behavioral Challenges in Responding to Climate Change," Norgaard's World Bank white paper.
Posted: 09 Dec 2009 09:53 AM PST
Crucially, the new plants wouldn't burn natural gas, they'd feed it to solid oxide fuel cells, electrochemical devices that convert the energy stored in the gas into electricity through a chemical reaction that's more efficient than traditional combustion.
Theoretically, the plant would be able to turn heat into electricity with an efficiency of 74 percent, as compared with just 50 percent at the very best natural gas plants (.pdf). And what's left over isn't the mix of gases that traditionally goes up a power plant's smokestack, but relatively pure water and carbon dioxide.
"Because we're keeping the nitrogen out of there, it's very, very easy to take the CO2 out," said MIT engineer Tom Adams, co-author of a paper in the Journal of Power Sources on the new plant design.
Though some of the scientists who have been working on solid oxide fuel cells for a long time don't think the MIT model is realistic, it does showcase some of the advantages of solid oxide fuel cells that could make them a major part of the low-carbon energy future. Specifically, solid oxide fuel cells make capturing carbon dioxide emissions easier and less expensive compared to other ways of using fossil fuels.
"The basic point is that we're able to avoid the CO2-capture penalty," Adams said.
Adams and his co-author, MIT engineer Paul Barton, have built on a decade-long effort by the Department of Energy: The Solid Energy Conversion Alliance, a consortium of heavy-hitting fuel-cell scientists and companies like Siemens coordinated by the National Energy Technology Laboratory, has been working to develop solid oxide fuel cells for commercial use.
The group has been steadily progressing towards building fuel-cell power plants. Right now, solid oxide fuel cells like the ones described by Adams are nearing commercialization by Siemens, but at the kilowatt scale, not the megawatt scale. But Adams believes megawatt prototypes could be operational by 2012.
Fuel cells might not sound like the hottest field in energy, but that might be because you're thinking about the wrong kind of fuel cell.
"You say fuel cells and it's like the kiss of death," said Michael Tucker, a chemical engineer at Lawrence Berkeley National Laboratory who is researching new ways of making fuel cells. "But that's because [people] associate the fuel cell with two things: the hydrogen economy, which doesn't exist, and PEM fuel cells, the hydrogen kind."
PEM, or polymer electrolyte membrane, fuel cells can convert hydrogen into electricity with the help of a catalyst at fairly low temperatures. They were supposed to be used largely in transportation to power cars. Whatever their merits, they haven't had the impact that some analysts predicted years ago.
But solid oxide fuel cells are different. While they are conceptually less attractive because they run at high temperatures (more than 1,500 degrees Fahrenheit) and high pressures (10 times atmospheric pressure), they don't require the fragile membranes and expensive catalysts made from precious metals like PEM cells do.
Despite this savings, the cost of solid oxide fuel cells is still too high, which is a major deterrent to their adoption.
"There needs to be a benefit to overcome cost differential," said Tucker. "You need to offer something better, and cheaper."
Right now, projections by backers of solid oxide fuel cells show that if they were able to manufacture them in large numbers, they'd be commercially competitive, Tucker said. But it's hard to know if those projections are realistic. Despite all the technical advances and DOE-directed research, cheap fuel cells still aren't really on the market.
"There is a reason that you can't buy one," said Tucker. "No one wants one at the cost that they can manufacture it at."
He's working on a new way of making the fuel cells largely out of stainless steel instead of the ceramic commonly used. This could be radically cheaper than the current technology, which would make it competitive with standard power sources.
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