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Stephen Colbert, host of the nightly 'The Colbert Report,' said in a new NASA public service announcement released today that he's always been a huge fan of space.

A controversial proposal would regulate sugar as a toxic substance, and not simply because it’s a calorie-rich enabler of obesity. Some researchers say it’s intrinsically dangerous, not unlike alcohol or tobacco, with unique properties that set off a hormonal cascade ending in higher risks of heart disease, stroke and type 2 diabetes.

It’s not a scientifically certain proposition, though a growing body of research suggests it may very well be true, and the implications are thorny. Even people sympathetic to public health-based regulations may balk at treating pastries as cigarettes, as University of California, San Francisco nutritionists suggested in a Feb. 2 Nature paper.

But to anyone looking to artificial sweeteners as an alternative, as pastel-packaged reassurances that regulators won’t ever need to pry donuts from their cold, dead and pudgy hands, science offers only more uncertainty. Some studies even suggest that fake sugar may cause the same problems as real sugar.

“That’s the $64,000 question,” said Susan Swithers of the Ingestive Behavior Research Center at Purdue University. “There are several epidemiological studies showing increased risk of metabolic syndrome in coincidence with the consumption of diet sodas” — a rich source of sweeteners. “But how they should be interpreted is not really clear right now. Because they’re correlational studies, they don’t tell us what caused what.”

Artificial sweeteners are a fast-growing, multi-billion dollar product, present in thousands of foodstuffs and synthesized by chemists as zealously as drug researchers pursue blockbuster drugs. But as described in a massive 2008 American Journal of Clinical Nutrition Review, the seemingly obvious health benefits expected of low-calorie sugar replacements have failed to materialize.

Even as Americans consumed more sweeteners, waistlines continued to expand. Cause and effect was ambiguous: Sweeteners might lead to weight gain, but maybe people most prone to gaining weight consume the most sweeteners. “This association may be coincidental or causal, and either mode of directionality is plausible,” concluded that study’s authors.

'Artificial sweetener use might be fueling -- rather than fighting -- our escalating obesity epidemic.'Other researchers, however, are more suspicious. When University of Texas Health Science Center epidemiologists conducted a 9-year-long study of 5,158 adult residents of San Antonio, Texas, they found a link between sweeteners and obesity. It persisted even after statistically accounting for gender, ethnicity, diet and beginning-of-diet body mass index. “These findings raise the question whether artificial sweetener use might be fueling — rather than fighting — our escalating obesity epidemic,” they wrote.

Another study of 6,184 adult Americans linked diet soda consumption with higher rates of metabolic syndrome, the umbrella term for a physiological disruption that leads to heart disease, stroke and type 2 diabetes. Once again, the link survived statistical adjustment for demographics, lifestyle and diet.

That’s precisely what’s expected from eating too much sugar, which at least in rats is converted in the liver to fat. That in turn provokes, via as-yet-unidentified mechanisms, resistance to insulin, a hormone used by cells to process glucose, better known as blood sugar. When insulin’s signals are ignored, blood sugar levels rise. Metabolic syndrome follows. But why should this happen when eating fake sugar, not real?

Swithers thinks she knows. In 2008, she and fellow Purdue researcher Terry Davidson fed rats a yogurt supplement sweetened either with glucose, a simple sugar, or zero-calorie saccharin. Apart from the supplement, both groups ate standard rat fare. Those that ate saccharin packed on more fat, gained more weight and consumed extra calories. A follow-up 2009 study reinforced the findings, and found that unusual weight gain persisted even when rats stopped eating sweeteners.

According to Swithers, two mechanisms may be responsible. When the rats’ bodies learned that sweetness didn’t predict an imminent caloric rush, as would naturally be produced by sugar-rich foods, their bodies may have automatically shifted into calorie-saving mode. At the same time, metabolic acceleration that normally occurs when eating high-calorie foods, and helps to process them, may have been slowed.

“All of our work has been in rats. We think similar processes happen in humans, but we haven’t tested them,” Swithers said.

Image: Steve Snodgrass/Flickr

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Photos like this could pass for a Cold War-era Russian propaganda program, or perhaps shots straight from the set of the movie Moonraker — if not for a stray pair of late-20th century sneakers.

Renowned fashion photographer Arthur Elgort, now 72, actually created these images for the December 1999 issue of Russian Vogue. (The magazine is owned by Conde Nast, which also owns Wired.)

In the images, supermodel Natalia Semanova mingles with real-life cosmonauts at Star City, a town northeast of Moscow and home of the Yuri Gagarin Cosmonaut Training Center, where for more than 50 years the Russian Federal Space Agency has trained willing citizens to fly in space. (Recently they’ve also been trained to survive 520 days inside a tin can.)

The photos experienced a recent resurgence in social media circles, so Wired tracked down Elgort to learn more about the timeless photos.

Wired: What led you to merge the worlds of fashion, science and technology for this shoot?

Arthur Elgort: I find it more interesting to put fashion in a setting that is different. Anywhere that the story can be about places that enhance the clothes.

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All images by Arthur Elgort and used with permission from Russian Vogue

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The European Space Agency’s Rosetta spacecraft is heading for a comet.

The ambitious mission — scheduled to enter orbit around Comet 67P/Churyumov-Gerasimenko in January of 2014 and place a tiny lander named Philae on its surface the following November — will no doubt return incredible, never-before-seen pictures. Until then, observers on Earth will have to make do with artists’ renderings like the ones in this video.

In past decades, about a dozen probes have performed comet flybys, sending back photographs of their nuclei. In 2005, NASA’s Deep Impact spacecraft shot a projectile that hit comet Temple 1.

But Rosetta and Philae will be the first mission to enter orbit around a comet and attempt a controlled landing onto its surface. The comet’s gravity is weak and its surface uneven, so Philae will shoot harpoons into the ground to help anchor it.

The probe will get to watch as the icy comet comes to life. Currently just a frozen ball of ice and dust, Churyumov-Gerasimenko will soon feel heat from the solar wind. Eventually, this radiation will melt the comet’s surface, generating a spectacular tail for Rosetta to observe.

The mission is named after the famed Rosetta stone, which allowed archeologists to decipher ancient Egyptian hieroglyphics. Since comets are frozen remnants from our solar system’s formation, researchers hope that the probe will help them understand how the planets came to be.

Image: Astrium - E. Viktor/ESA

Video: NASA

By Mark Brown, Wired UK

Last week, NASA released its 2012 version of the famous “Blue Marble” image. By using a planet-pointing satellite, Suomi NPP, the space agency created an extremely high-resolution photograph of our watery world.

The photo centered on the western hemisphere, highlighting North and Central America. It went viral and got even more hits on Flickr than the iconic “Situation Room” photo, taken at the time of the assassination of Osama bin Laden.

Now, responding to public demand, the agency has created a companion image: this time focusing its lens toward the East and showing Africa, Saudi Arabia and India.

The Suomi NPP satellite hugs the Earth too closely to get this kind of image in one shot. It’s in a polar orbit with an altitude of 824 kilometers, but the perspective of the Eastern hemisphere Blue Marble is from 12,743 kilometers away.

As such, Nasa Goddard oceanographer Norman Kuring used images from six different orbits of the satellite over an eight-hour time period on Jan. 23, then stitched the photos together to achieve the final composite.

Both of the 2012 Blue Marble images are taken by a new instrument aboard Suomi NPP called the Visible Infrared Imaging Radiometer Suite (VIIRS). As for those four vertical lines: That’s the reflection of sunlight off the ocean, or “glint,” that VIIRS captured as it orbited the globe.

Other famous photos of Earth include the original Blue Marble, which was taken on Dec. 7, 1972, by the crew of the Apollo 17 spacecraft. There’s also the equally famous 2002 one, which you might recognize as the default lock screen on the first iPhone. Plus “You Are Here,” an arresting photo of Earth from the surface of Mars, snapped by the Spirit rover in 2004.

Image: NASA/NOAA [high-resolution]

Source: Wired.co.uk

More than 6,300 individuals applied to become a NASA astronaut between Nov. 15, 2011 and Jan. 27, the second highest number of applications ever received by the agency.

NASA's Glenn Research Center (GRC) in Cleveland will host a special event on March 2 to celebrate the 50th anniversary of John Glenn's first orbital flight by an American.

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Toxic barbs on a cucumber’s skin, nanoscopic flakes of metal and a mouse’s technicolor eyeball (above) are just a few of 2011′s top science visualizations.

A panel of judges picked the best of more than 200 entries from 33 countries for the 2011 International Science and Engineering Visualization Challenge.

“I think because information technology tools and visualization tools have advanced, people have found ever-increasingly clever ways to display difficult scientific concepts,” said competition judge Thomas Wagner, a cryosphere scientist at NASA, in an interview provided by the contest.

Contest judges made their picks based on visual impact, originality and clarity. The winners, which include “people’s choice” awards as well as honorable mentions, were published online Feb. 2 in the journal Science.

The entries weren’t just limited to photographs. Contest categories also included illustrations, informational graphics, videos and even interactive video games.

See the best of these science and engineering visualizations in this gallery.

Images and videos courtesy of AAAS/Science

Above:

Mouse Eyeball Cells

Researchers stained ultra-thin slices of a mouse’s eye to create this first-place photography winner.

The stain was made of three antibodies that bind to three different molecules present in all cells, but in differing concentrations. Assigning red, blue and green to each antibody allowed the creators to depict more than 70 different cell types in the organ.

Image: Bryan William Jones/University of Utah/Moran Eye Center [high-resolution]

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By Mark Brown, Wired UK

After 20 years of drilling, a team of Russian researchers is close to breaching the prehistoric Lake Vostok, which has been trapped deep beneath Antarctica for the last 14 million years.

Vostok is the largest in a sub-glacial web of more than 200 lakes that are hidden 4 km beneath the ice. Some of the lakes formed when the continent was much warmer and still connected to Australia.

The lakes are rich in oxygen (making them oligotrophic), with levels of the element some 50 times higher than what would be found in your typical freshwater lake. The high gas concentration is thought to be because of the enormous weight and pressure of the continental ice cap.

If life exists in Vostok, it will have to be an extremophile — a life form that has adapted to survive in extreme environments. The organism would have to withstand high pressure, constant cold, low nutrient input, high oxygen concentration and an absence of sunlight.

The conditions in Lake Vostok are thought to be similar to the conditions on Jupiter’s moon Europa and Saturn’s tiny moon Enceladus. In June, NASA probe Cassini found the best evidence yet for a massive saltwater reservoir beneath the icy surface of Enceladus. This all means that finding life in the inhospitable depths of Vostok would strengthen the case for life in the outer solar system.

Back on planet Earth, the team at Vostok are running short on time. Antarctica’s summer will soon end and the researchers need to leave their remote base while they still can. Temperatures will drop as low as -80C, grounding planes and trapping the team.

They missed their chance last year. “Time is short, however. It’s possible that the drillers won’t be able to reach the water before the end of the current Antarctic summer, and they’ll need to wait another year before the process can continue,” we wrote in January 2011. The drill halted in February.

Meanwhile, Russian engineers are planning to venture into the lake itself, with swimming robots. In the Antarctic summer of 2012 to 2013, they plan to send a robot into the lake to collect water samples and sediments from the bottom. An environmental assessment of the plan will be submitted at the Antarctic Treaty’s consultative meeting in May 2012.

Image: Wikipedia/NASA

Source: Wired.co.uk

A view across the Santorini caldera. The newest eruptions in the caldera can be seen on the right on Nea Kameni.

This appears to be a week of media interest in new journal articles. Earlier, I discussed a study that claimed that volcanoes were the cause of the onset of the Little Ice Age. Now, we have a study in Nature that discusses the magmatic events that lead up to the Minoan eruption at Santorini – a fairly timely topic considering the rumblings there – that has gotten the media’s attention.

Now, I’m not going to pick apart this paper by Timothy Druitt and others as such – the study, called “Decadal to monthly timescales of magma transfer and reservoir growth at a caldera volcano“, is actually quite solid. The long-and-short of the study is that they examined plagioclase feldspar crystals looking at the zoning of different elements in these crystals (see below).

There are two main pieces to the study. First, if a crystal grows in a certain magma, it will suck in certain amounts of different elements – some are major constituents of the minerals. In plagiolclase feldspar, we can define the “An” of a crystal by looking at proportions of Ca and Na in the crystal (high “An” means high Ca – closer to the perfect feldspar endmember anorthosite). The “An” can then tell us if a crystal came from one type of magma or another (see figure below). If there are low abundance elements in the mineral, like strontium, magnesium and titanium in plagioclase feldspar, then the amount of the element is controlled by the partitioning of the element between the liquid magma (melt) and the crystal. This is what geologists call the “partition coefficient” – or how likely is an element to want to be in the crystal or melt. The partition coefficient will change depending on the overall composition, pressure and temperature of the magma and crystal, so crystals in different magmas will suck up different amounts of these elements. This gives them distinctive compositions depending on the magma in which they grew – a “compositional signature” so to speak. (Note: I looked that is in zircon from the Okataina Caldera in my Earth and Planetary Science Letters study from last year).

Part of Figure 1 from Druitt et al. (2012) that shows the zoning of plagioclase feldspar from the Minoan eruption of Santorini.

The second piece is diffusion. Elements in crystals will diffuse back into the melt (or vice versa) if there is a large compositional gradient between the crystal and the melt. So, throw a crystal of one composition into a new magma of another, the elements will begin to exchange over time starting at the rim of the crystal. So, assuming specific thermal parameters and compositional gradients, you can use diffusion as a clock – how long has the foreign crystal been exposed to this new magma based on how much diffusion of certain elements has occurred. Now, different elements have different abilities to diffused based on their size and charge, so you need to choose wisely.

The Druitt et al. (2012) study used these two petrologic characteristics of minerals and melt to determine two main conclusions: (1) the magma erupted from Santorini during the Minoan eruption in ~1600 BC was a mixed magma and (2) the intrusion that “got the ball rolling” towards the Minoan eruption and the subsequent mixing happened geologically quickly – in the the timescales of a century to a few months. Now, there is a big caveat not mentioned in the study to this second point. One quandary we have in petrology is that when we look at timescales of processes inside magmatic systems, diffusion profiles like the kind used in this study imply events occur much faster than if you try to date mixed crystals using radiometric elements (such as Ra, Th and U). This disconnect has not been resolved, so I would say that the timescales suggested by Druitt et al. (2012) are minimum timescales for the intrusion and mixing, not maximum. This will be important later on.

You might have noticed a lot of the media coverage about this study is claiming things like “supervolcanoes offer 100 year early warning” and “they may be predicted”. That is never said in the study. The authors do discuss some of the ways that this recharge/mixing might be manifested once the events have begun – interestingly not as “bulging” but rather “sagging” of the bottom of the magmatic system as the magma fills in, so uplift at Santorini might have been minimal. They actually predict that sinking of the land surface might be more likely rather than the classic St. Helens-1980-style bulge.

However, what I see as the biggest problem in this “early warning” claim is that it might still not be easily detectable – what if their timescale is off by even a factor of 2, so it takes 2 centuries to lead to an eruption? Human monitoring of an event 200 years in the making might be very problematic. Secondly, this intrusion isn’t a big event at 100 years than than over, it is growth and mixing over that century with a rapid culmination only months before the eruption according to Druitt et al. (2012). Whether or not this is detectable by current monitoring methods is unclear as well. The authors are right about one thing: “Long-term monitoring of large, dormant caldera systems, even in remote areas of the world, is essential if late-stage growth spurts of shallow magma reservoirs are to be detected well in advance of caldera-forming eruptions.” However, as usual, the many in the media has boiled down their research into meaningless copy that both misses the point of the research but also recklessly mischaracterizes the ramifications.

Image 1: Santorini caldera. Image by Navin75/Flickr.
Image 2: Figure 1 from Druitt et al., (2012)

NASA is seeking proposals for flight demonstrations of small satellite technologies with the goal of increasing the technical capabilities and range of uses for this emerging category of spacecraft.

NASA will host a media telecon at 2 p.m. CST today to discuss the status of the International Space Station and the progress toward an updated launch schedule, including international partner and commercial space vehicles.

NASA Administrator Charles Bolden will lead a discussion with business leaders and higher education professionals at a Listening and Action Session of the President's Council on Jobs and Competitiveness from 8:30 a.m. to 10 a.m. PST on Friday, Feb. 3, in Seattle.

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Moving big animals to places they don't already live is at once appealing and disturbing, a sort of adolescent environmental fantasy come to life: African lions in Nebraska! Komodo dragons in Australia!

But at the beginning of the 21st century, with 7 billion humans competing for space and resources on a rapidly warming planet, exercising arguable control over the fate of nature, moving species around is a legitimate option.

It's called assisted migration. Often the goal is to save endangered plants and animals, though not always. Sometimes, as with the Komodo dragon proposal, the goal is to restore ecological balance, and other proposals are motivated by an almost romantic sense of possibility: Wouldn't it be marvelous to watch cheetahs dash across the grasslands of South Dakota?

As an idea, assisted migration has been around for decades, but since the millennium's turn it's moved from a mostly fringe concept to something that scientists discuss, if not argue. After all, many examples of unwittingly assisted migration show what can happen when relocation goes wrong: Cane toads swarming across Australia, brown tree snakes devouring Guam's birds, kudzu swallowing much of the southeastern United States, and of course the voracious Burmese pythons of Florida.

On the flip side, however, are pheasants and sweet clover, brown trout and Norway maple, which despite their non-native origins are now considered a natural part of North American life. Sometimes relocation works fine, and an argument can be made that consciously acting as landscape-scale zookeepers and gardeners is a legitimate response to impending catastrophe.

Above:Komodo Dragons to Australia?

In a Feb. 1 Nature paper, biologist David Bowman of Australia's University of Tasmania raises the hypothetical possibility of introducing elephants and Komodo dragons to Australia. At first it sounds mad, but what's happening now in Australia is a form of madness, too. Massive wildfires that have become a regular and lethal fact of Australian life don't only represent climate change or natural susceptibility, but the buildup of vegetation that until 50,000 years ago would have been eaten by Australia's now-extinct megafauna.

Elephants could fill that role again, writes Bowman. "The idea of introducing elephants may seem absurd, but the only other methods likely to control gamba grass involve using chemicals or physically clearing the land, which would destroy the habitat," he writes. "Using mega-herbivores may ultimately be more practical and cost-effective." Komodo dragons wouldn't do much for fires, but they would eat feral pigs and buffalo, the targets of ongoing and largely unsuccessful animal control efforts.

Image: Komodo dragon (Adhi Rachdian/Flickr)

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This 30-second clip was captured by one of NASA’s twin GRAIL satellites on Jan. 19, the first movie taken of the moon’s far side by the mission.

The entire far lunar hemisphere appears in the video, starting with the moon’s north pole. It then pans down over well-known features such as the giant impact basin Mare Orientale, located off to the right, and the prominent Drygalski crater, seen left of center, which contains a distinctive star-shaped formation created when a comet or asteroid smacked into the moon billions of years ago.

Because the moon is tidally locked to Earth, it always shows the same familiar face to our planet. The other hemisphere is sometimes referred to as the ‘dark side of the moon,’ though it actually receives equal sunlight as the facing side during the moon’s orbit.

Other than small slivers, the far side of the moon had never been seen by humanity before the space age, when the Soviet Luna 3 took pictures of it in 1959. The crew of Apollo 8 — Frank Borman, James Lovell, and William Anders — was the first to directly observe the far side in 1968.

Video: NASA

Photo: Gnissah/Wikimedia

Spider silk is well known for some spectacular properties. It is stronger than steel and tougher than Kevlar yet flexible enough to be spun into a wide variety of shapes.

New research shows that the material is not only strong but also smart.

“Spider silk has a particular way of softening and then being stiff that is really essential for it to function properly,” said engineer Markus J. Buehler of the Massachusetts Institute of Technology, who co-authored the new study, which appears in Nature Feb. 2.

A spider web provides its occupant with a home and a way to catch prey. It needs to stand up to pesky attackers and sometimes withstand hurricane-force winds. Using computer models of spider silk and experiments on the webs of common European garden spiders (Araneus diadematus), Buehler and his team found a web’s unique skills come from its ability to react differently to different stress levels.

A light wind, for instance, softens the web, allowing it to lengthen but retain its overall structure. If a larger force is applied at a specific location, such as when a particular thread is poked, the silk becomes rigid and breaks.

Furthermore, only the most extended silk threads get severed. Having small portions of the web come apart not only helps retain the overall structural integrity but actually makes the web stronger. The researchers found that removing up to a tenth of the threads at different locations allowed the structure to carry 3 to 10 percent more weight. This shows the web’s advantage over materials such as steel, which would simply break apart under such conditions.

The work provides insight into spiders’ success with catching prey, said biologist Todd A. Blackledge of the University of Akron in Ohio, who was not involved in the study. “It’s really important for the silk to stretch under impact, cradling the insect so it doesn’t bounce out,” he said.

Engineers could also apply the secrets of spider silk to other challenges, Buehler suggested. Its ability to sustain small damage without compromising the entire structure could be useful in designing virtual networks, such as the Internet, where a local node gets sacrificed during an attack to keep the whole system from going down. Understanding how its microscopic protein structure gives rise to its macroscopic properties might help in stringing together carbon nanotubes, which may one day be used to produce objects ranging from combat gear to space elevators.

A camera aboard one of NASA's twin Gravity Recovery And Interior Laboratory (GRAIL) lunar spacecraft has returned its first unique view of the far side of the moon.

Students participating in a U.S. Coast Guard Academy mentoring program will speak with Expedition 30 Commander Dan Burbank aboard the International Space Station at 11:15 EST on Thursday, Feb. 2.

NASA has received the National Research Council (NRC) report "NASA Space Technology Roadmaps and Priorities," which provides the agency with findings and recommendations on where best to invest in technologies needed to enable NASA's future missions in space.

NASA and the University of Maryland's A. James Clark School of Engineering invite the public to a discussion with three astronauts from recent International Space Station expedition missions at 5:30 p.m. EST on Tuesday, Feb. 14, in the Hoff Theater inside the Adele H. Stamp Student Union.