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Alt-week 7.8.2012: Solar flares, trapping dark matter, and life-sized Lego trees

Alt-week peels back the covers on some of the more curious sci-tech stories from the last seven days.

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This week we swing by some superhero news, look at how solar panels might shape up in the future, explore a Lego forest and see how to grab dark matter just using some household gold and strands of DNA. Not only that, we discover how the sun likes to celebrate the fourth of July with its own firework display. This is alt-week

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While the majority of the science community had its eyes firmly fixed on one elusive atomic unicorn, small steps were being made in finding another -- dark matter. Scientists have hung a lot of theory on this invisible peg, and its very nature is also what makes it hard to find. After all, how do you find something that neither emits nor absorbs light? Well, as it happens many great minds are trying to figure that out, and one of the latest approaches comes with a bunch of cunning.

The coordinated effort involves University of Michigan's Katherin Freese and Harvard's George Church, along with some DNA and some gold. Obviously. The gold is laid out in a thin sheet, with the DNA hanging below it in threads, and the idea is that the clumsy dark matter will collide with the gold atoms, forcing it out of the sheet and cutting through the DNA like grass. As each strand of DNA has an identifier, this also means the trajectory can be worked out. Simple.

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You know who else's DNA got messed up? That's right, Spider-man. With the latest installment in the movie franchise hitting cinemas this week, we were pleased to find out that directors have been consulting scientists directly to sharpen up their in-film academia. What now? In short, rather than have a theater full of tutting students, directors are consulting people like James Kakalios (author of The Physics of Superheroes no less) to make sure they create "a believable fake reality." Want to know exactly what that entails? Well the short answer is entertaining on-screen physics based on laboratory truths. For the slightly longer, yet no less interesting answer, tune your spidey sense to the video below.

Us mere mortals might never get radioactive powers, but we can distil energy from the sun, and that's pretty heroic. This week we saw a new study come to light that could lead to the improvement of photovoltaic (PVT) solar systems. Although PVT panels can provide both heat and power, they're much better suited to the latter. To address this imbalance, Joshua Pearce from Michigan Technological University, along with Michael Pathak and Stephen Harrison outlined a solution that uses amorphous -- or thin film -- silicon. Despite being lighter, cheaper and greener, this type of silicon suffers from the "Staebler-Wronski" effect, where efficiency declines in light. No good for solar panels obviously.

The new study, however, discovered that by heating the thin-film silicon to about 100 degrees Celsius (212 Fahrenheit) which is the solar-thermal operating temperature, the Staebler-Wronski effect was largely negated. A further 10 percent increase in efficiency was achieved by spike annealing -- essentially baking -- the cell once a day. This means that the thermal energy created by PVT panels is improved, and it also means that, in the future, they could be used for both purposes, meaning less roof-top real estate, and a happier planet (and possibly wallet).

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From one hot topic, to another: solar flares. This week, of course, many of us were enjoying fourth of July celebrations. Space.com reports that the sun has been putting on its own fireworks display, with impressive flares being seen firing off from sunspot AR1515. The eruptions registered in as a class M5.3 solar storm (with X being the only class higher). The sunspot responsible is about 100,000 kilometers long (roughly eight times the earth's diameter,) and the flares come at a particularly active phase of the current 11 year solar cycle, -- which is expected to peak next year. So, compared to that, San Diego's "display" this year might look relatively tame.

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While the sun's energy is generally considered good for most trees, we're not sure the ones you see below will react in quite the same way. Broken Hill -- a small mining city in Australia -- has suddenly found itself surrounded by forest. Not just any old arboreal collection either, these trees are of the rare "life-size Lego" variety. All part of Lego's Festival of Play celebrations, the jumbo plastic installation will be in place between July 2nd and the 12th. The models are "1:1 replicas" of the stuff you buy, but "super-sized by a factor of 66" says Lego. The group of 13-foot tall pines are accompanied by 15 flower sets, and cut a distinctive contrast against the baron red soil of the outback. Most impressively, it's reported that locals were surprised to see the new synthetic landscape upon awaking one morning, and were apparently unaware of the stunt.

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Seen any other far-out articles that you'd like considered for Alt-week? Working on a project or research that's too cool to keep to yourself? Drop us a line at alt [at] engadget [dot] com

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European Spallation Source AB: Opposites Repel: ESS Scientist Discovers New Magnetic Phenomenon

STOCKHOLM--(BUSINESS WIRE)--For the first time, a novel magnetic state has been discovered, where the most basic concept of magnetism - that opposites attract - does not hold true. The phenomenon has been discovered and described by an international team of scientists lead by ESS Director for Science Dimitri Argyriou. The discovery holds promise for tomorrow's memory and sensor technology, enabling devices from phones to cars. The finding was reported in Nature Materials.

Phones, cars, TVs and kitchen appliances - most of the tools we use have small computers inside, and they all require memory. Product development proceeds at breakneck pace, and the computers have to be ever smaller, smarter, more energy efficient. In pursuit of tomorrow's data-handling technology, researchers at the European Spallation Source have unearthed a novel magnetic phenomenon.

No one can say what the next big breakthrough in data-handling technology will be, but a class of materials called multiferroics are promising candidates. One such material is terbium ferrite, which can store information so that it can be written with electricity and read magnetically, at a low energy cost. This may revolutionise memory and sensor technology - but a lot of research is required before the concept can be used in applications.

An international research team lead by Dimitri Argyriou, Director for Science at ESS, Sweden, has used neutrons to probe the inner workings of terbium ferrite. They found that at an atomic scale, the atoms arrange themselves in a grid of microscopic domains, each of which behaves like a small bar magnet. These magnets do not line up in the same direction, as one might expect. Instead, adjacent domains have opposite magnetic directions, placing north next to north and south next to south. The scientists were also surprised by the overall domain structure: they are unexpectedly large (albeit on a microscopic scale) and display extremely sharp domain boundaries.

- I was expecting domains perhaps 30 times smaller than what we observed, says Dimitri Argyriou. And the domain boundaries are exceptionally sharp - I've never seen anything like it. The structure shouldn't be stable, and yet it is.

Pursuing this mystery, the team of professor Maxim Mostovoy, a theoretical physicist at Groningen University, the Netherlands, provided a surprising insight. The unusual structure observed - large domains with sharp domain walls and alternately arranged magnetic moments - is stabilized by a novel magnetic phenomenon. Surprisingly, the opposite poles of a domain repel each other. Rather than red attracting white and red repelling red as with bar magnets, in terbium ferrite, opposites repel.

– Our discovery has many implications, says Maxim Mostovoy. We think that this interplay between iron and terbium atoms can be used to make new, more versatile multiferroics that can cover the increasing demands of lean technology with low power consumption.

This discovery previews the discoveries that ESS, the European facility for research with neutrons under development in southern Sweden, will bring.

– Without neutrons, this discovery would have passed us by, says Dimitri Argyriou. We need more powerful neutron sources in order to probe deeper into such new states of matter. Once built, ESS will help us unearth new phenomena like this one, which remain hidden from us today. This is one example of the many new things a facility like ESS will help us discover, not only in magnetic materials, but in a broad range of fields of science and technology.