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Saturday, April 19, 2008

Fifty Years of American Space Exploration [Slideshow]

NASA celebrates half a century of American spaceflight with a new collection of space exploration images


FIRED UP FOR THE FUTURE | Slide 1 of 7

The laboratories managed by NACA (the National Advisory Committee for Aeronautics, which was replaced by NASA in 1958) were at the forefront of the development of reliable high-performance jet-propulsion engines. In this 1946 test, engineers at the Flight Propulsion Research Laboratory in Cleveland take motion pictures of exhaust gases being discharged from a burner used for studying thrust augmentation in jet engines. As is often the case in aerospace engineering studies, the camera is an essential tool for data analysis.

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Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2008 April 18

IC 2948: The Running Chicken Nebula
Credit & Copyright: Steve Crouch

Explanation: Bright nebulae abound in and around the expansive southern constellation of Centaurus. This one, cataloged as IC 2948 is near the star Lambda Centauri and not far on the sky from the better known Eta Carinae Nebula. Embedded in the reddish glowing cloud of hydrogen gas, typical of emission nebulae found in massive star-forming regions, is the energetic young star cluster IC 2944. Seen in silhouette near the top of the view are small, dark clouds of obscuring cosmic dust. Called Thackeray's Globules for their discoverer, they are potential sites for the formation of new stars, but are likely being eroded by the intense radiation from the nearby young stars. Of course, gazing at the center of the region suggests to some IC 2948's popular name - The Running Chicken Nebula. The gorgeous skyscape spans about 70 light-years at the nebula's estimated 6,000 light-year distance.

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Mars radar opens up a planet’s third dimension

Radar sounding is opening up a planet’s third dimension

17 April 2008
ESA’s Mars Express radar sounder, MARSIS, has looked beneath the martian surface and opened up the third dimension for planetary exploration. The technique’s success is prompting scientists to think of all the other places in the Solar System where they would like to use radar sounders.

No matter how accurate a camera is, it can only map a planet’s surface. To retrieve information about the underground realm, planetary scientists in the past would have thought it necessary to land on the surface and start digging. But that would only be good for a single spot on a large planet and the first few decimetres of the surface.


Martian south polar layered deposits

Martian south polar layered deposits
To get the global picture of the subsurface they need a radar sounder, such as the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS), to find the best spots for the future landers to go and dig.

MARSIS was an experiment in every sense of the word. “It was a leap into the unknown,” says Ali Safaeinili, MARSIS co-investigator at the Jet Propulsion Laboratory (JPL), California, USA.

No one had ever used a radar sounder from orbit on another planet before. So the team could not even be sure whether it would work as planned. The subsurface of the planet might have been too opaque to the radar waves or the upper levels of martian atmosphere (ionosphere) might have distorted the signal too much to be useful. Thankfully, none of this happened.

“We have demonstrated that the polar caps at Mars are mostly water ice, and produced an inventory so now we know exactly how much water there is,” says Roberto Orosei, MARSIS Deputy Principal Investigator, IASF-INAF, Italy.



MARSIS sending signals and receiving echoes

Armed with a better understanding of how planetary radar sounders work, the MARSIS team is beginning to look further afield in the Solar System, to other bodies that might benefit from radar investigation. One obvious target is Jupiter’s icy moon, Europa.

A MARSIS-type experiment in orbit around Europa could probe its icy crust to help understand the puzzling features we see on the surface. It may even see the interface at the bottom of the ice where an ocean is expected to begin.

At Saturn’s moon, Titan, penetrating radar could be used to measure the depths of the hydrocarbon lakes that the Cassini spacecraft has detected. It could also probe the structure beneath the enigmatic geysers that Cassini has observed on another one of Saturn’s satellites, Enceladus. “Radar sounders are very well suited to exploring icy worlds,” says Orosei.


MARSIS completely deployed

MARSIS fully deployed
But not just for icy moons. Asteroids and comets could be thoroughly scanned by a radar sounder, producing three-dimensional maps of their interior – perhaps exactly the data we will need if, one day, we have to nudge one out of Earth’s way.

MARSIS has served as an excellent example of international collaboration between Europe and America. Increasingly, such collaborations are set to become a positive feature of our joint exploration of space.


For more information, read the full article on the ESA Mars Express pages

The MARSIS technique could prove invaluable for studying the stability of Antarctic ice sheets here on Earth, read more on ESA General Studies Programme pages

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Ion engine enters space race

Vacuum testing chamber at Qinetiq
The test chamber is one of the biggest in Europe

Engineer Neil Wallace peers into a huge vacuum chamber designed to replicate - as far as possible - the conditions of space.

Cryogenic pumps can be heard in the background, whistling away like tiny steam engines.

Using helium gas as a coolant, they can bring down the temperature in the vacuum chamber to an incredibly chilly 20 Kelvin (-253C). The pressure, meanwhile, can drop to a millionth of an atmosphere.

This laboratory in a leafy part of Hampshire is where defence and security firm Qinetiq develops and tests its ion engines - a technology that will take spacecraft to the planets, powered by the Sun.

Ion engines are an "electric propulsion system". They make use of the fact that a current flowing across a magnetic field creates an electric field directed sideways to the current.

This is used to accelerate a beam of ions (charged atoms) of xenon away from the spacecraft, thereby providing thrust.

Neil Wallace, technical lead of the electrical propulsion team at Qinetiq, winds open the door of the testing chamber.

The most exciting time for us will be when that space craft comes over the horizon
Neil Wallace, Qinetiq

He points to some large metal blocks at the bottom of the chamber.

"These are the xenon pumps and these are cooled down by the helium compressors to approximately 20 degrees Kelvin," he explains.

"So any gas atoms that strike those panels, they freeze. After you've been running the engines for a number of hours you can see a frost - it looks like snow - which is actually frozen air and xenon."

During testing, the engine fires ions towards the opposite end of the chamber, which has a protective coating of graphite.

"The ions are travelling very fast, at approximately 50km a second," he says.

"When they strike the other end of the chamber, they actually knock atoms off the surfaces they strike; it's analogous to sand-blasting on an atomic level."

Cruise control

The ion engine developed by Qinetiq, the T5, will be flown for the first time on the European Space Agency's Goce spacecraft. The mission will fly just 200-300km above the Earth, mapping the tiny variations in its gravity field.

GOCE - EUROPE'S GRAVITY EXPLORER
Goce (BBC)
1. The 1,100kg Goce is built from rigid materials and carries fixed solar wings. The gravity data must be clear of spacecraft 'noise'
2. Solar cells produce 1,300W and cover the Sun-facing side of Goce; the near side (as shown) radiates heat to keep it cool
3. The 5m-by-1m frame incorporates fins to stabilise the spacecraft as it flies through the residual air in the thermosphere
4. Goce's accelerometers measure accelerations that are as small as 1 part in 10,000,000,000,000 of the gravity experienced on Earth
5. The UK-built engine ejects xenon ions at velocities exceeding 40,000m/s; Goce's mission will end when the 40kg fuel tank empties
6. S Band antenna: Data downloads to the Kiruna (Sweden) ground station. Processing, archiving is done at Esa's centre in Frascati, Italy
7. GPS antennas: Precise positioning of Goce is required, but GPS data in itself can also provide some gravity field information


A replica of the T5 engine sits in the test facility at Qinetiq. It is tiny - weighing 3kg, and looks rather like the oil filter of a car.

Yet despite this humble appearance, it took 20 to 30 years to develop, at a cost of tens of millions of pounds.

In space, ion engines will draw electric power from solar panels, generating a thrust equivalent to the weight of a postcard.

This incredibly gentle thrust could, in theory, take a spacecraft beyond our Solar System, if sustained for long enough.

Goce is staying very close to Earth, flying in an ultra-low orbit, where it will encounter wisps of air.

The benefit of an ion engine on this mission is to provide drag compensation, or cruise control.

"This spacecraft is [travelling] at a speed of about eight and a half kilometres per second," says Neil Wallace.

"As it travels around the Earth, it's going through the upper atmosphere and it experiences a buffeting.

"They need to compensate that buffeting very accurately and that's what we're doing, so we're actually providing cruise control for that spacecraft."

Real flight

Various types of ion engine have been used before on only a handful of space missions, including Smart-1, the European mission to the Moon, and Nasa's Deep Space 1, which flew by a comet.

Goce ion engine mounted in test chamber (Qinetiq)
The T5 ion engine being tested

Future Esa missions such as BepiColombo, bound for the innermost planet, Mercury, will also use the technology.

Qinetiq gets to test its T5 engine for real this summer, when Goce is launched from the Russian space port of Plesetsk. It will go up on the same type of rocket that failed three years ago, destroying Europe's Cryosat ice mission.

Neil Wallace says the nature of the space business makes watching any launch a dramatic event.

"You spend 10 years working on a mission, treating the components and equipment like a newborn baby. You never take it out of the clean room, and then you put in on the top of 100 tonnes of high explosive and set light to it," he says, laughing nervously.

"But no, the most exciting time for us will be when that spacecraft comes over the horizon and the ground station picks it up, and you can see the engines are doing what we've always said they will do."

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Is there anybody out there?

Is there anybody out there? Probably not, according to a scientist from the University of East Anglia. A mathematical model produced by Prof Andrew Watson suggests that the odds of finding new life on other Earth-like planets are low, given the time it has taken for beings such as humans to evolve and the remaining life span of Earth.
Structurally complex and intelligent life evolved late on Earth and it has already been suggested that this process might be governed by a small number of very difficult evolutionary steps.

Prof Watson, from the School of Environmental Sciences, takes this idea further by looking at the probability of each of these critical steps occurring in relation to the life span of Earth, giving an improved mathematical model for the evolution of intelligent life.

According to Prof Watson a limit to evolution is the habitability of Earth, and any other Earth-like planets, which will end as the sun brightens. Solar models predict that the brightness of the sun is increasing, while temperature models suggest that because of this the future life span of Earth will be ‘only’ about another billion years, a short time compared to the four billion years since life first appeared on the planet.

“The Earth’s biosphere is now in its old age and this has implications for our understanding of the likelihood of complex life and intelligence arising on any given planet,” said Prof Watson.

“At present, Earth is the only example we have of a planet with life. If we learned the planet would be habitable for a set period and that we had evolved early in this period, then even with a sample of one, we’d suspect that evolution from simple to complex and intelligent life was quite likely to occur. By contrast, we now believe that we evolved late in the habitable period, and this suggests that our evolution is rather unlikely. In fact, the timing of events is consistent with it being very rare indeed.”

Prof Watson suggests the number of evolutionary steps needed to create intelligent life, in the case of humans, is four. These probably include the emergence of single-celled bacteria, complex cells, specialized cells allowing complex life forms, and intelligent life with an established language.

“Complex life is separated from the simplest life forms by several very unlikely steps and therefore will be much less common. Intelligence is one step further, so it is much less common still,” said Prof Watson.

His model, published in the journal Astrobiology, suggests an upper limit for the probability of each step occurring is 10 per cent or less, so the chances of intelligent life emerging is low – less than 0.01 per cent over four billion years.

Each step is independent of the other and can only take place after the previous steps in the sequence have occurred. They tend to be evenly spaced through Earth’s history and this is consistent with some of the major transitions identified in the evolution of life on Earth.

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Is "Nerdic" Really the Fastest Growing Language?

According to Pixmania.com's research, the speedy growth of consumer electronics and associated buzzwords and acronyms has created the "fastest growing language" in Europe. The study says it's more widely spoken than any single European language and is used by all ages. More words get added to it each year than are added to the Oxford English Dictionary. Hmmmm. What exactly is this "nerdic"? Read on for what the study suggests are the top ten words/phrases... and why we think it's all rubbish.

Pixmania's top ten: WiMax, Rickroll, UGC, mashup, RFID, Android, HDMI, fuel-cell, HSDPA and DVB-H.

There's also a "bottom ten" list too, which includes dial-up, KB and, of course, HD DVD.

And what's this about it being a language? Of course global adoption of a technology adds certain phrases to all languages— I mean, just a small bunch of decades ago few people would've understood the words "cellphone" or "hard drive" or "SCART." But does that really make it a language? No, it's not even a dialect. Does it even help non-nerds understand the tech they're buying, no matter what country they're buying it in? Remember the consumer frenzy that stirred up around digital cameras and the megapixel race? And the multitude of terms about HD TV: all that 1080i, 720p (really 768p) nonsense?

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What happens when you pop a quantum balloon?

When a tiny, quantum-scale, hypothetical balloon is popped in a vacuum, do the particles inside spread out all over the place as predicted by classical mechanics?

The question is deceptively complex, since quantum particles do not look or act like air molecules in a real balloon. Matter at the infinitesimally small quantum scale is both a wave and a particle, and its location cannot be fixed precisely because measurement alters the system.

Now, theoretical physicists at the University of Southern California and the University of Massachusetts Boston have proven a long-standing hypothesis that quantum-scale chaos exists … sort of.

Writing in the April 17 edition of Nature, senior author Maxim Olshanii reported that when an observer attempts to measure the energies of particles coming out of a quantum balloon, the interference caused by the attempt throws the system into a final, “relaxed” state analogous to the chaotic scattering of air molecules.

The result is the same for any starting arrangement of particles, Olshanii added, since the act of measuring wipes out the differences between varying initial states.

“It’s enough to know the properties of a single stationary state of definite energy of the system to predict the properties of the thermal equilibrium (the end state),” Olshanii said.

The measurement – which must involve interaction between observer and observed, such as light traveling between the two – disrupts the “coherent” state of the system, Olshanii said.

In mathematical terms, the resulting interference reveals the final state, which had been hidden in the equations describing the initial state of the system.

“The thermal equilibrium is already encoded in an initial state,” Olshanii said. “You can see some signatures for the future equilibrium. They were already there but more masked by quantum coherences.”

The finding holds implications for the emerging fields of quantum computing and quantum information theory, said Paolo Zanardi, an associate professor of physics studying quantum information at USC.

In Zanardi’s world, researchers want to prevent coherent systems from falling into the chaos of thermal equilibrium.

“Finding such ‘unthermalizable’ states of matter and manipulating them is exactly one of those things that quantum information/computation folks like me would love to do,” Zanardi wrote. “Such states would be immune from ‘decoherence’ (loss of quantum coherence induced by the coupling with environment) that’s still the most serious, both conceptually and practically, obstacle between us and viable quantum information processing.”

Zanardi and a collaborator introduced the notion of “decoherence-free” quantum states in 1997. Researchers such as Zanardi and Daniel Lidar, associate professor of chemistry, among others, have helped make USC a major center for the study of quantum computing.

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NPR, Science Channel, and Expelled??

The Expelled movie producers are, as we know from copious evidence, lying and evil.

Nefarious even. They placed ads for their antiscience propaganda piece on The Science Channel and NPR.

Evil does as evil is, so I’m not surprised they would try that. But I am really shocked that TSC and NPR would take their money. This movie is totally 100% against the missions of both The Science Channel and National Public Radio. It is seriously like taking the KKK’s money for ads, or from NAMBLA. Why would you do that?

I have not seen the TSC ads, but I was pretty surprised when I was poking around the NPR site and an ad for the movie popped up in a media player (I was looking for a podcast about the LHC, a scientific triumph, making the ad that much more appalling). PZ mentions it as well.

What they heck were they thinking?

I am too busy right now to draft up appropriate letters, but feel free to do so yourselves (after due diligence if you so desire). If I get a chance I’ll be taking care of that when I get back from Europe.

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Double Your Lifespan with a Drug that Mutates Your Ribosomes

ribosome1.jpg It's been known for a while that restricting your diet will increase your lifespan, but now researchers have shown one reason why: Eating less causes your ribosomes (your cells' protein factories) to mutate. And it's looking like mutated ribosomes (pictured here) could be one key to life extension. The good news is that you may not have to starve yourself to mutate your ribosomes anymore. Biologists at the University of Washington have managed to induce the life-extending mutation in ribosomes with a drug that doubles the lifespan of yeast cells.

The key is to lower protein-production in cells, which is why eating less can cause lifespan extension. According to the University of Washington:

In this project, the UW researchers studied many different strains of yeast cells that had lower protein production. They found that mutations to the ribosome, the cell's protein factory, sometimes led to increased life span. Ribosomes are made up of two parts — the large and small subunits — and the researchers tried to isolate the life-span-related mutation to one of those parts.

"What we noticed right away was that the long-lived strains always had mutations in the large ribosomal subunit and never in the small subunit," said the study's lead author, Kristan Steffen, a graduate student in the UW Department of Biochemistry.

The researchers also tested a drug called diazaborine, which specifically interferes with synthesis of the ribosomes' large subunits, but not small subunits, and found that treating cells with the drug made them live about 50 percent longer than untreated cells. Using a series of genetic tests, the scientists then showed that depletion of the ribosomes' large subunits was likely to be increasing life span by a mechanism related to dietary restriction — the TOR signaling pathway.

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Scientists make music into mathematical shapes

The two-note chords form a Mobius strip, whose boundary is a 'trefoil knot'
The two-note chords form a Mobius strip, whose boundary is a 'trefoil knot'

We know it has pitch and beat. But it turns out that music has a distinct shape too.

  • In search of the last chord and winter colds
  • In the wake of centuries of effort to seek deep connections between music and mathematics, a team today concludes that music does have geometry.


    More than 2000 years ago, Pythagoras discovered that pleasing musical intervals could be described using simple ratios. And the idea of the so-called musica universalis or "music of the spheres" emerged in the Middle Ages which said that the proportions in the movements of the celestial bodies - the sun, moon and planets - could be viewed as a form of music, inaudible but perfectly harmonious.

    Now, three music professors - Clifton Callender at Florida State University, Ian Quinn at Yale University, and Dmitri Tymoczko at Princeton University - have devised a new way of analysing and categorising music to reduce musical works to their mathematical essence, suggesting that mathematics is a more fundamental language of nature than music.

    Following a pioneernig effort by Prof Tymoczko in 2006, the trio has now outlined a method called "geometrical music theory" in the journal Science that they say can turn music into shapes.

    "To me," Prof Tymoczko says "the most satisfying aspect of this research is that we can now see that there is a logical structure linking many, many different musical concepts. To some extent, we can represent the history of music as a long process of exploring different symmetries and different geometries."

    "Our methods are not so great at distinguishing Aerosmith from the Rolling Stones," Tymoczko said. "But they might allow you to visualise some of the differences between John Lennon and Paul McCartney. Paul McCartney's tunes tend to look more traditional, John Lennon's tunes tend to be a little more "rock" - violating more of the traditional rules.

    And they certainly help you understand more deeply how classical music relates to rock or is different from atonal music.

    "The team can take sequences of notes, like chords, rhythms and scales, and categorize them so they can be grouped into "families."

    They have found a way to assign mathematical structure to these families, so they can then be represented by points in complex geometrical spaces, much the way "x" and "y" coordinates, in the simpler system of high school algebra, correspond to points on a two-dimensional plane.

    This achievement, they expect, will allow researchers to analyse and understand music in much deeper and more satisfying ways. "The music of the spheres isn't really a metaphor - some musical spaces really are spheres," said Tymoczko, who like Callender is also a composer.

    "The whole point of making these geometric spaces is that, at the end of the day, it helps you understand music better. Having a powerful set of tools for conceptualizing music allows you to do all sorts of things you hadn't done before."

    "You could create new kinds of musical instruments or new kinds of toys," he said. "You could create new kinds of visualisation tools - imagine going to a classical music concert where the music was being translated visually. We could change the way we educate musicians. There are lots of practical consequences that could follow from these ideas."

    The work represents a significant departure from other attempts to quantify music, according to Rachel Wells Hall of the department of mathematics and computer science at St. Joseph's University in Philadelphia. In Science, she writes that their effort, "stands out both for the breadth of its musical implications and the depth of its mathematical content."

    Original here


    Nano switch hints at future chips

    Dr Leonid Ponomarenko, associate researcher
    Dr Leonid Ponomarenko shows off a device with the transistor embedded

    Researchers have built the world's smallest transistor - one atom thick and 10 atoms wide - out of a material that could one day replace silicon.

    The transistor, essentially an on/off switch, has been made using graphene, a two-dimensional material first discovered only four years ago.

    Graphene is a single layer of graphite, which is found in the humble pencil.

    The transistor is the key building block of microchips and the basis for almost all electronics.

    Dr Kostya Novoselov and Professor Andre Geim from The School of Physics and Astronomy at The University of Manchester have been leading research into the potential application of graphene in electronics and were the first to separate a sheet of the material from graphite

    Super material

    Graphene has been hailed as a super material because it has many potential applications. It is a flat molecule, with only the thickness of an atom, and both very stable and robust.

    The researchers are also looking at its use in display technology - because it is transparent.

    The Manchester-based scientists have shown that graphene can be carved into tiny electronic circuits with individual transistors not much larger than a molecule.

    Dr Novoselov told BBC News that graphene had many advantages over silicon because it could conduct electricity faster and further.

    Silicon will be replaced by graphene
    Dr Kostya Novoselov

    "These transistors will work and work at ambient, room temperature conditions - just what is required for modern electronics," he said.

    Dr Novoselov said graphene was a "wonderful conductor", making it a perfect material for chip applications.

    "It is already superior to silicon by an order of magnitude and comparable to the best samples of other materials.

    "We believe we can increase this mobility of electron flow 10-fold."

    Graphene is a hot topic among semiconductor researchers at the moment because it is an excellent conductor of electricity. Unlike silicon graphene transistors perform better the smaller they become.

    Leak electricity

    The global semiconductor business is currently built on sand; stamping out microchips from large silicon wafers.

    Companies like Intel have a roadmap to reduce the size of circuits on the silicon wafer, down to about 10 nanometres - 10,000 times smaller than the width of a single human hair.

    Many researchers believe that producing circuits smaller than 10 nanometres in silicon will be too difficult because they start to leak electricity at that size.

    That current silicon roadmap is expected to end in 2020, making the race to find alternative materials potentially very lucrative.

    Producing graphene sheets big enough to be used as wafers for chip production remained the biggest hurdle, said Dr Novoselov.

    "We can control the cut down to 20 nanometres. And then when we have to scale down to one nanometre we use a bit of luck.

    "The yield of the working devices is about 50%."

    Many researchers around the world are working on creating large wafers of graphene.

    In order to produce microchips wafers would need to be several inches across. The biggest wafer produced so far is 100 microns across, just a tenth of a millimetre.

    Electron microscope view of the graphene transistor
    Short and narrow constrictions in graphene can act as high-quality transistors

    "I do believe we will find the technology to do this. And when we do silicon will be replaced by graphene," said Dr Novoselov.

    Professor Bob Westervelt, in an assessment of the material and its future application in the journal Science, wrote: "Graphene is an exciting new material with unusual properties that are promising for nanoelectronics.

    "The future should be very interesting."

    Dr Novoselov added: "Given the material was first obtained by us four years ago, we are making good progress."

    He said the process of using graphene to build circuits was very compatible with silicon technology.

    "At the moment we use all the same steps to make a transistor as is done by the silicon industry. So once we have large wafers of graphene it should be straightforward to use the same process."

    But it might be another 10 years before the first integrated circuits on graphene chips appear, he said.

    Shorter term

    In the shorter term graphene could be used in LCD displays to replace materials used to create transparent conductive coatings.

    "The computer screen relies on good transparent conductors. But current materials are expensive and hard to produce.

    "Graphene is only one atom thin so is absolutely transparent - it's a really wonderful conductor.

    "We propose to use it as a transparent conductor, using small interconnecting graphene sheets all together."

    The material is also being touted for use in solar panels, transparent window coatings and also for sensing technologies.

    Original here


    ArcAttack brings singing Tesla coils to the masses


    ArcAttack's performances include two singing Tesla coils, a robotic drum set and a PVC pipe organ.

    (Credit: ArcAttack)

    When you think of things related to science, music may not make the top of your list.

    But the folks involved with a small collective called ArcAttack would like you to change your associations.

    ArcAttack is all about one thing: building singing Tesla coils and crafting entire musical performances around them. For some time, at events like Dorkbot and other geekfests, the team--Joe DiPrima, Oliver Greaves, and Tony Smith--had been pulling off straightforward demonstrations of their creations. But they were synchronizing the machines to other people's music and not adding much in the way of their own innovations besides the singing Tesla coils themselves.

    Now, however, ArcAttack has a whole ensemble mixing science and music and plastic--the Tesla coils, a pipe organ made from PVC, a robotic drumset--and putting it all together in short concerts with original music.

    "We've got a solid 45 minutes or so of original content," DiPrima, an engineer at the University of Texas, told me recently, "and sometimes we'll incorporate themes from popular songs or do mixups with video game music.



    When you see the singing Tesla coils, it takes a minute to really understand what you're watching. At first, you don't hear the tunes in the crackling of the electricity. But after a few moments, you realize what you're hearing and it's startling--especially if you have any experience with Tesla coils--to see these scientific wonders spitting out little bits of lightning with a beat.

    "I've always loved music--playing it, and electronics too," DiPrima said. "I've been in a lot of bands, along with the other guys in the group, and this is probably the most fun we've had out of any other project we've been in. The way people respond to the coils playing real music with other instruments involved is amazing. People love it."

    In particular, DiPrima suggested, ArcAttack's performances give their audiences--both in person and on the Web--a sense that music and science can indeed blend in a way that teaches something.

    For many people, music is not the first thing they would associate with a Tesla coil, but ArcAttack has managed to build entire performances around its singing versions of the geek-favorite machines.

    (Credit: ArcAttack)

    "It's...a great way to get people interested in the science behind it," he said, "to present a Tesla coil, not just (as) an 'air core resonant transformer,' but (as) an effective tool for high intensity music."

    Original here

    Japan’s cyborg research enters the skull

    Mind-controlled robot arm -- Researchers at Osaka University are stepping up efforts to develop robotic body parts controlled by thought, by placing electrode sheets directly on the surface of the brain. Led by Osaka University Medical School neurosurgery professor Toshiki Yoshimine, the research marks Japan’s first foray into invasive (i.e. requiring open-skull surgery) brain-machine interface research on human test subjects. The aim of the research is to develop real-time mind-controlled robotic limbs for the disabled, according to an announcement made at an April 16 symposium in Aichi prefecture.

    Although brain waves can be measured from outside the scalp, a stronger, more accurate signal can be obtained by placing sensors directly on the brain — but that requires open-skull surgery, making it more difficult to recruit volunteer test subjects.

    The researchers, who have filed a license application with the Osaka University Hospital ethics board, are working to enlist willing subjects already scheduled to have brain electrodes implanted for the purpose of monitoring epilepsy or other conditions. The procedure, which does not involve puncturing the cortex, places an electrode sheet at the central sulcus, a fold across the center of the brain near the primary motor cortex (which is responsible for planning and executing movements).

    To date, the researchers have worked with four test subjects to record brain wave activity generated as they move their arms, elbows and fingers. Working with Advanced Telecommunications Research Institute International (ATR), the researchers have developed a method for analyzing the brain waves to determine the subject’s intended activity to an accuracy of greater than 80%. The next step is to use the data to control robot arms developed by the University of Tokyo’s Department of Precision Engineering.

    Original here

    Carbon mesh pins down universal constant

    Carbon mesh pins down universal constant
    Graphene, a mesh of carbon one atom thick, has been used to finally pin down a mysterious universal constant.
    Image: Thomas Szkopek

    SYDNEY: The world's thinnest material can shed light on the exact measurement of one of the universe's fundamental physical constants, a new study reveals.

    Researchers led by physicist Andre Geim from the University of Manchester in the U.K., used graphene – a sheet of carbon just one atom thick – to gauge the exact measurement of the fine structure constant, a fundamental physical constant defining the interaction between fast moving electric charges and light.

    Their results were published online in the current edition of the journal Science Express, ahead of publication in the U.S. journal Science.

    The fine structure constant was first introduced by physicists in attempts to understand atomic structure and has long mystified scientists because there seemed to be no natural mathematical relationship that described the constant, like a circle's circumference divided by its diameter describes the universal constant pi.

    Foundations of life

    In this new study, the U.K. and Portuguese researchers shone light through sheets of graphene and found that it absorbs a surprising amount of light considering its extreme thinness. The material's opacity is due to its molecular structure: a mesh of carbon atoms and bonds that looks something like chicken wire (when rolled up, graphene forms carbon nanotubes and when piled in layers it forms graphite).

    They found that the exact value of light absorbed by graphene – 2.3 per cent of visible light – divided by pi gives the value of the fine structure constant (approximately 1/137). As the researchers point out, few other universal constants can be described so simply.

    "We were absolutely flabbergasted when we realised that such a fundamental effect could be measured in such a simple way. One can have a glimpse of the very foundations of our universe just looking through graphene," said Geim, who was part of the team that discovered graphene in 2004.

    "Change this fine-tuned number by only a few per cent and life would not be here because nuclear reactions in which carbon is generated from lighter elements in burning stars would be forbidden. No carbon means no life," he added.

    Acting like light

    Theoretical physicist Ross McKenzie from the School of Physical Sciences and the Centre for Organic Photonics and Electronics (COPE) at the University of Queensland, Australia, describes the research as "very beautiful".

    "It's rare in condensed matter physics to get something so clean and elegant, particularly in the way the theory agrees with the experiment," he said.

    Graphene can be used to calculate the fine structure constant because its crystal structure is unique among solids, according to McKenzie. As electron waves travel through the crystal, the symmetry of the carbon atoms forces the relationship between the electron wavelength and energy to be the same as the relationship for photons in light. As a result, the electrons effectively act as photons, but move at a much slower velocity. This property in turn leads to other unique properties that rely on the fine structure constant.

    Chemical physicist Paul Meredith, also from COPE, said the research represents a "great leap forward" in terms of manipulating graphene. "The first step towards making a device, especially a nanoscopic device, is the ability to manipulate this material and they've cracked it," he said.

    Graphene has very high conductivity so could be used in a variety of structured electronic materials, Meredith said. Possible uses include flexible transparent electronics or transparent electrodes for solar cells, as well as innovative uses in medicine.

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    Sexually transmitted bug is the strongest organism

    Pound-for-pound, it's the strongest organism ever. This mighty beast is the gonorrhea bacterium – the strongest creature alive.

    These tiny creatures can pull with a force equal to 100,000 times their body weight – as though a human could drag 10 million kilos.

    Many bacteria produce filaments called pili. These are a hundred times as long as they are wide and up to ten times longer than the bacterium itself. They can also contract. Scientists knew that Neisseria gonorhoeae bacteria use "type four" pili to crawl along a surface and to attach to cells and infect them.

    What they didn't know was that these bacteria can bundle pili together to exert long, strong pulls. Michael Sheetz and colleagues at Columbia University in New York put the bacteria in a field of tiny gel "pillars" and measured the amount the bacteria could bend them as a way of measuring the force of their pull.

    Short and long

    They mostly saw a lot of short grabs. But one pull in a hundred started out at the same strength as these short pulls, then increased in increments about equal to the force of the original pull, as if the bacteria were calling in more individual pili to help out the first.

    This eventually resulted in a pull that was up to ten times stronger than the initial short grab, and it could last for several hours.

    See video of the bacteria pulling the pillars here and here.

    Electron microscopic images confirmed the bundles. They also revealed that the reason scientists have not seen this before is because a protein usually added to bacterial culture medium happens to block it.

    Great motor

    The actual force the bacteria exerted was around a nanoNewton, or one billionth of a Newton, the force you would need to accelerate a kilogram by a metre per second squared.

    Not a lot – but it means the bacteria can pull with a force equivalent to 100,000 times its bodyweight, and hold it. This, say the authors, makes the retraction protein in the pili "the strongest biological motor known to date".

    "This constitutes a new paradigm for the generation of forces in the biological realm," Sheetz and colleagues say, and could completely change our understanding of the way gonorrhea bacteria muscle up to cells and infect them.

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    I'll grow marigolds on the moon, says scientist

    Marigolds could be growing on the moon by around 2015, if an ambitious effort by scientists pays off.

    In what marks an important step towards helping lunar colonists grow their own food, a Ukrainian team, working with the European Space Agency, ESA, has shown that marigolds can grow in crushed rock very like the lunar surface, with no need for plant food.

    Marigolds can grow on the moon
    Marigolds were shown to survive in crushed rock

    The research was presented at the European Geosciences Union meeting in Vienna, by Dr Bernard Foing of ESA, director of the International Lunar Exploration Working Group, and father of the SMART-1 moon probe, who believes it is an important milestone because it does away with the need to bring bringing nutrients and soil from Earth.

    He has worked with Natasha Kozyrovska and Iryna Zaetz from the Ukranian Academy of Sciences in Kiev, who planted marigolds in crushed anorthosite, a type of rock found on Earth which is very similar to lunar soil, called regolith.

    They did not grow well until the team added different types of bacteria, which made them thrive; the bacteria appeared to leach elements from the rock that the plants needed, such as potassium.

    Even better, bacteria are able to withstand extremely tough conditions, so would be an ideal way to fertilise lunar crops. “That is the new aspect of this work,” says Dr Foing, who presented the study at the EGU meeting, said there was no reason in principle why the same idea could not bear fruit on the Moon itself.

    He is pinning his hopes on a ESA proposal for a mission called Moon Next, which would probably deploy a roving vehicle in about 2015, or on a subsequent Lunar Logistics Lander, scheduled for 2016-17.

    As well as marigolds, he says that tulips, cabbages and arabidopsis (a weed, the most studied plant on the planet) could be grown on the moon.

    Tulips are handy because they can be frozen, transported long distances and grown with little nourishment. Combined with algae, an enclosed artificial atmosphere and the bacterially enhanced lunar soil, they could form the basis of a precursor lunar “ecosystem.”

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    How Does Global Warming Affect Wildlife?

    The National Wildlife Federation considers global warming to be "the most dangerous threat to the future of wildlife." Here are just some of the species being dramatically impacted by global warming.

    Learn how global warming affects the adelie penguin

    Adelie Penguins
    When many of us think of Antarctica, it is with visions of waddling, tuxedoed penguins. Today, however, these iconic creatures may be in peril as a result of changes to their climate. Rising temperatures are causing the amount of sea ice to diminish, which in turn causes the amount of algae in the water to decrease. Many tiny organisms, including the krill shrimp which forms the foundation of the Adelie penguin’s diet, cannot survive without this important food source.

    Learn how global warming affects the caribou

    Caribou
    Almost everyone knows how annoying mosquitoes can be, but if you happen to be a caribou, these common summertime pests can have an even bigger impact. This is because warming Arctic temperatures have caused an explosion in these insects' populations. As caribou expend more energy shooing the pests away, they decrease the amount of food that they eat and energy that they conserve in preparation for the coming winter months. Female caribou are particularly at risk as the effort of birthing and raising the new generation takes enormous energy.

    Learn how global warming affects the monarch butterfly

    Monarch Butterflies
    Brilliant orange and black monarchs are among the most easily-recognizable of the butterfly species which call the Americas home. Their migration takes them as far north as Canada and, during the winter months, as far south as Mexico City. It is here that changing conditions could cause their demise if current climatic trends continue into the future. In Mexico, the butterflies amass themselves in fir trees which provide shelter from rain and temperatures which often dip below freezing. As rainfall worldwide continues to increase, the protection that these trees provide may not be enough to shield the butterflies from these hazards. One mass die-off occurred in 2002; scientists fear that this is the first of many similar incidents.

    Learn how global warming affects the Western tanager

    Migratory Songbirds
    The songs of many migratory birds, such as this Western tanager, are welcomed symbols of springtime. Warmer seasons worldwide may mean that you won’t be hearing some of those old familiar songs in years to come, however, as songbirds are particularly sensitive to changes to both temperatures and their habitats.

    Learn how global warming affects the polar bear

    Polar Bears
    Polar bears, like their favored springtime prey the ringed seal, depend heavily on sea ice for their survival. Polar bears move from ice flow to ice flow in search of the young seals. With rising temperatures, the thinning ice leaves fewer places for both the polar bears to hunt and the seals to raise their young.

    Learn how global warming affects trout

    Trout
    Coldwater fish, such as trout, depend on a frigid mixture of spring and glacier water to thrive. As North American temperatures continue to rise, trout stand to lose three-quarters of their current habitat. Before long, an enitre generation of Anglers will have lost the the ability to bond with friends and family while communing with nature.

    Learn how global warming affects coral reefs

    Coral Reefs
    Coral reefs are colorful underwater forests which teem with life and act as a natural protective barrier for coastal regions. The fishes and plants which call them home belong to some of the most diverse – and fragile – ecosystems on the planet. In one year alone, sixteen percent of the world’s coral reefs were wiped out. A sea temperature change of a mere one degree Celsius would yield similar losses. Increasing levels of carbon dioxide in the water cause additional damage to corals, leaving them defenseless against storm damage and erosion.

    Learn how global warming affects the arctic fox

    Arctic Foxes
    The arctic fox is a marvel or environmental adaptation. Its paws are covered with thick fur to protect its feet in winter, and it is an excellent burrower which allows it to dig dens and warm itself against the arctic chill. In recent years, warmer temperatures have driven the arctic fox farther and farther north in search of more suitable, cooler habitat.

    Do your part to help reduce global warming by taking the Good Neighbor Pledge today!


    Next step: Watch a video on global warming and wildlife

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    How many gallons of water do you need to power a lightbulb?

    Here's a measurement you probably haven't thought of before: it takes between 3,000 gallons and 6,000 gallons of water to power a 60-watt incandescent bulb for 12 hours a day over the course of a year.

    The water equation comes to energy.

    (Credit: Virginia Tech)

    That statistic was published on Thursday by researchers at Virginia Polytechnic Institute and State University, who have studied how demand for a dwindling natural resource--fresh water--plays into energy.

    The most water-efficient energy sources are natural gas and synthetic fuels produced by coal gasification. The least efficient are ethanol and biodiesel--two fuels booming in production because of supportive government policies, followed by rapid investment.

    In terms of power generation, they found that geothermal and hydroelectric energy use the least amount of water, while nuclear plants use the most.

    A United States-wide tally shows that power generation requires 655 billion gallons of water a year.

    "There are several variables, such as geography and climate, technology type and efficiency, and accuracy of measurements that come into play. However, by standardizing the measurement unit (BTU, or British Thermal Unit), we have been able to obtain a unique snapshot of the water used to produce different kinds of energy," Virginia Tech professor Tamim Younos said.

    Biofuels, in particular, are being increasingly scrutinized, as people start to measure the trade-offs of making liquid fuels from biomass.

    Corn ethanol emits about 20 percent fewer greenhouse gases than gasoline, but it requires more water, and it has raised the price of grain and food.

    Fresh-water supply is a serious concern among scientists studying climate change. Recent droughts in Europe and the southeast United States have been blamed for strains on production at nuclear and coal power generation facilities.

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    Gibraltar to cull Barbary apes that terrorise tourists

    Gibraltar apes face cull
    Vets will track down the tearaways and kill them by lethal injection.

    Gibraltar's iconic monkeys are facing a cull after terrorising tourists on the British colony.

    A pack of 25 of the Barbary macaques have “run riot” on a beach, have broken into hotel rooms and have been caught scavenging in bins in the town centre.

    The threat of attacks on humans and the possibility of the spread of disease has forced authorities to approve the cull “as a last resort”.

    Ernest Britto, Gibraltar’s tourist minister, defended the plans for the cull, saying: “Children are frightened. People cannot leave their windows open for fear of the monkeys stealing. “Apes can bite, and contact with them runs the risk of salmonella or hepatitis.”

    Vets are to track down the tearaways and put them down by lethal injection. Two have already been killed.

    The Gibraltar population of the Barbary macaque – a monkey commonly referred to as the Barbary ape because of its stubby tail – numbers more than 200.

    They attract hundreds of tourists every day to the areas around Apes Den and the Siege Tunnels at the top of the Rock.

    Francis Cantos, the spokesman for the Government of Gibraltar, insisted: “This is being done as a last resort.

    “The apes we are targeting are part of a breakaway group that are going into town and making a nuisance as well as posing health hazards.

    “They’ve been spotted going through rubbish, vandalising property and stealing from people. They ran riot at the beach at Catalan Bay.”

    The cull has the backing of many locals including staff at Gibraltar’s Caleta Hotel, where guests’ rooms were vandalised recently by apes looking for food.

    However, the decision to destroy the rogue pack has been condemned by animal protection groups.

    Helen Thirlway, the conservation and welfare director for the International Primate Protection League (IPPL) in the UK, said the monkeys were the colony’s most popular tourist attraction and the “needless slaughter has to stop”.

    British soldiers are thought to have introduced the apes, natives of north Africa, into Gibraltar in the mid-18th century to use for shooting practice.

    Local folklore has it that the colony would cease to be British if the monkeys were to leave.

    Winston Churchill took it seriously enough to ship extra monkey from north Africa to Gibraltar during the Second World War.

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