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Study Shows 'Megadrought' May Soon Hit Southwestern U.S.

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Cattle stand on drought-stricken land in California in October 2011.
Tim McCabe/USDA Natural Resources Conservation Service via Wikimedia Commons

The American Southwest may be headed for a “megadrought,” an arid period longer than any in recent memory.

A megadrought is the name for a decades-long dry spell. Researchers have known since 1998 that megadroughts can occur in the region. Under normal conditions, dry periods of several decades or more come once or twice in a millennium, but the changing climate has made the danger much more imminent. Now, a new study has determined there is a 50 percent chance that a drought as long as 35 years will occur in the next century. And the chances of another decade-long drought are as high as 80 percent.

In order to understand the conditions that lead to these rare multi-decade dry periods, researchers went into the field to study the traces that ancient weather patterns leave behind. “You go up into the mountains and these beautiful places where moisture limits growth to take samples,” Dr. Toby Ault, lead researcher of the study, tells Popular Science.

In dry places, plants grow slower and the gaps between their annual tree rings are shorter. By matching up modern tree rings with ancient wood -- such as beams from pre-Columbian Native American desert dwellings -- researchers can track annual moisture patterns going back centuries. That’s an important part of how they know the Southwest has been through megadroughts before, as well as how often they've happened.

Plus, climate models have long predicted the Southwest will lose water as the Earth warms, and the prolonged drying period predicted for the coming years looks eerily similar to the periods that preceded the sustained dry periods of the past.

“This pretty robust feature of climate change models loads the dice toward droughts and megadroughts,” Ault says.

Decade-long droughts came about once a century in the pre-climate change world. Today, California and Arizona are parched. An ongoing 15-year drought is sucking dry the region’s reservoirs and drying out its forests, leading to a range of problems, including immediate concerns about water shortages in Tucson, Phoenix, and even Las Vegas.

There is some uncertainty as to the relationship between the region’s current struggles and climate change, but this drought points to what the whole Southwest may have to deal with if droughts become more widespread and longer-lasting. A megadrought could include New Mexico and Texas, and last as long as 35 years.

However, Ault says a megadrought in our lifetimes would not have to mean devastation for the American Southwest.

“Some of our best evidence of droughts comes from tree rings,” he points out. “That means some trees grew during dry periods. A megadrought doesn’t spell death and destruction for all creatures. Less water does not mean no water.”

Ault says he hopes his findings will encourage state and local water conservation groups to deal with the danger of water scarcity becoming the norm. Advances in water conservation and management have prevented the current Arizona drought from becoming as bad as the Dust Bowl, a shorter dry spell that devastated American plains agriculture during the Great Depression in the 1930s.

“As long as we accept that we are a clever and adaptable species -- and I think all evidence points to us being a clever and adaptable species -- we can mange this,” he says.


Cotton Vs. Polyester: Which Gym Clothes Trap The Most Body Odor?

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Spinning class
Working out burns calories, while making smelly skin microbes.
Frederiek-Maarten Kerckhof

Chris Callewaert wants to solve body odor, starting with your gym clothes.

He and a team of European microbiologists have tackled a stifling mystery that permeates locker rooms and laundry hampers across the world: Why does gym gear reek even days after a workout?

A fair assumption would be that some fabrics trap more sweat than others, but perspiration on its own is sterile and does not produce foul odors.

Instead, pungent bacteria from our skin grow more readily on certain workout shirts, namely those made from synthetic textiles like polyester, according to new research from Callewaert and his colleagues at Ghent University in Belgium.

The scientists had 26 healthy individuals – 13 men and 13 women – participate in a spinning class, while wearing T-shirts made from natural or synthetic fibers. After the exercise, the shirts were stuffed into plastic bags and stored in the dark, akin to tossing gym clothes into a musty locker. After 28 hours, an independent panel of odor connoisseurs judged that the polyester shirts stank worse than cotton-based ones.

Skin germs feast on chemicals in sweat, turning them into pungent odor compounds, which the bacteria subsequently “fart” out.

Next, the researchers swabbed the shirts’ armpit regions for bacteria. Skin bacteria produce many of the scents connected to bad body odor -- and armpits are microbe havens.

To understand just how prolific bacteria are on our bodies, grab a ruler and pen. Draw a square one centimeter by one centimeter on your forearm. Around 100 bacteria live inside that square. In contrast, an identical square on your armpit, navel, or toe web spaces carries 10 million bacteria.

The most common known cause of malodor is a family of skin microbes in the genus Corynebacterium; however, the scientists couldn’t spot any on sweaty gym gear.

Rather they found that soiled polyester shirts wound up harboring more Micrococci bacteria, a type of odiferous germ, than cotton shirts. The result was surprising because Micrococci don’t generally grow in pits.

“As part of a separate, ongoing study, we’ve screened over 200 people, and found very low levels of Micrococci present on armpit skin,” says Callewaert. “Something about sweat-filled polyester enriches these sour-smelling bacteria.”

Micrococcus luteus
Micrococci bacteria, a type of odiferous germ, were found in soiled polyester shirts.
Skin germs feast on chemicals in sweat, turning them into pungent odor compounds, which the bacteria subsequently “fart” out. While natural textiles absorb this stench-filled water, Callewaert and his colleagues suspect that the funky juice pools in the microscopic spaces in between synthetic fibers, creating a great environment for bacteria to flourish.

To explore this idea, the team took a few pungent species of bacteria and tried growing them in Petri dishes coated with seven different fabrics: polyester, acryl, nylon, fleece, viscose, cotton, and wool.

The results were mixed. Cotton grew very few smelly germs, akin to earlier findings, while the microbes continued to swarm over polyester.

Synthetic nylon was a great refuge for Propionibacterium acnes, a species of bacteria that causes acne and foot odor. Natural wool supported every germ tested, while the scientists found one fabric – viscose – where bacteria didn’t grow.

This preliminary study could help inform clothing makers on how to create less smelly apparel.

“Many manufacturers have started adding antimicrobials, like nanosilver, to their clothes,” says coauthor Nico Boon, a microbial ecologist at Ghent University.

Such chemicals eliminate germs indiscriminately, meaning the good germs disappear with the bad. “This could potentially throw off our immune systems,” Boon continues. “We should manage and control the existing microbial community, so that we steer the germs in the way that we want, instead of killing everything,”

To keep garb from trapping workout odor, he and Callewaert recommend clothing hybrids, where the fabric coming in contact with armpits is made from cotton. The rest of the shirt could be synthetic fabric, which accumulates less heat and feels more comfy.

The researchers published their work in the journal Applied and Environmental Microbiology.

Should Tanks Be More Like iPhones?

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Iraqi Army Soldiers In Light Armored Vehicles, 2007
U.S. Marine Corps. photo by Lance Cpl. Julian Billmair, via Wikimedia Commons

When Iraq’s American-equipped army fled their posts in Mosul last June, they left that American equipment in the hands Islamic State of Iraq and Syria (ISIS), the attacking violent insurgent group. Since then, the U.S. Air Force destroyed some of the captured vehicles. Jonathan Zittrain, director of Harvard’s Berkman Center for Internet and Society, wonders if there’s a better way to stop stolen equipment from working. He proposes “kill switches,” like those found in iPhones, as a means for keeping American arms, given to allies, from working in the hands of enemies.

Here’s the key idea from Zittrain’s article:

It is past time that we consider whether we should build in a way to remotely disable such dangerous tools in an emergency. Other technologies, including smartphones, already incorporate this kind of capability. The theft of iPhones plummeted this year after Apple introduced a remote “kill switch,” which a phone’s owner can use to make sure no one else can use his or her lost or stolen phone. If this feature is worth putting in consumer devices, why not embed it in devices that can be so devastatingly repurposed—including against their rightful owners, as at the Mosul Dam?

Through email, Popular Science spoke with Zittrain about how these proposed killswitches could work, and what they would mean for arming allies in the future.

Popular Science: Cell phone kill switches work in a world filled with cellphone towers and internet connections--things that are rare on battlefields. I know you mention satellites, but what kinds of infrastructure do you think a kill switch would require?

Jonathan Zittrain: Some [military] hardware already relies on communications with a home base perhaps thousands of miles away. For example, remotely piloted drones. The technology used to securely direct drones might be usable for other instruments of war. Essentially, the more sophisticated and communications-based, such as relying upon military-grade GPS, the less of an incremental change a kill switch would represent.

PS: What kinds of military gear do you see as likely kill switch candidates?

JZ: Medium and heavy weaponry, including tanks, anti-aircraft missiles, helicopters, and jets.

PS: What safeguards could prevent an armed non-state actor from "jailbreaking" their killswitch-enabled MANPADS [Man Portable Air Defense Systems], tanks, or rifles?

JZ: No safeguard is foolproof, and physical possession of the gear in question is often thought of as "game over" from a hacking perspective. But if we see the problem in terms of time and effort to break the lock, rather than "can it ever be broken," there may be useful ways of integrating this technology, especially when balanced against the costs of misuse of the weapons should they be completely unsecured. (Right now we might depend on such things as batteries that naturally expire and are hard to replace, or other maintenance that an adversary won't be in a position to do.)

Steven Bellovin at Columbia has done a lot of thinking about this problem for nuclear weapons, which need to be hardened against use should they fall into someone's wrongful possession. He's written up his thoughts here.

One could also imagine an expiration date requiring renewal with a code or signal, so that no adversary could hack the switch itself and render the weapon useless even if it hadn't been stolen. At most the hacker could allow the weapon to continue operating past its due date.

Iraqi Army Patrolling Mosul, 2008
Staff Sgt. Jason Robertson, via Wikimedia Commons

PS: Many small arms in current use are decades old if not older. Would you support retroactively adding kill switches to these before distribution, or are kill switches more for advanced equipment?

JZ: I see them as more useful for more advanced equipment. With the world awash in small arms, it seems harder to make a dent in that supply.

PS: With kill switch-equipped weapons, do you think the United States or others would be more likely to arm friendly non-state actors?

JZ: This is a distinct possibility, and could mean that kill switches would, as a second-order effect, lead to more arms being sold or given to parties. If the worst uses can be foreclosed -- or we convince ourselves that they are -- it changes the downside risk of providing the arms to begin with.

PS: Kill switches come with a major trust issue. While America might promise killswitchable weapons to an allied army so that an insurgent can't use them, what assurance would the ally have that the kill switch wouldn't leave them vulnerable?

JZ: That assurance may already be in question. Any secret kill switches already in use would presumably be used rarely in order not to eliminate that trust. Here, stated up front, a recipient knows the conditions by which the arms are transferred. The easy case is the recipient possessing the kill switch; the more difficult is the providing country having it; the most radical would be for the UN Security Council or some other group to have to come to consensus to trigger the switch.

The Week In Drones: Chinese Pterodactyls, Ram Attacks, And More

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Grand Prismatic Spring And Midway Geyser Basin From Above
Brocken Inaglory via Wikimedia Commons

Here's a roundup of the week's top drone news: the military, commercial, non-profit, and recreational applications of unmanned aircraft.

Through A Scan Eagle Darkly

The ethics of drone warfare are coming to the silver screen. “Good Kill,” a film starring Ethan Hawke and directed by Andrew Niccol, focuses on an American drone pilot based in Nevada. The film debuted at the Venice Film Festival today. The director hopes it will spark debate. Here’s hoping some of that debate addresses the mental health challenges that come with being a drone pilot.

Charges Against Prismatic Pilot

In August, a Dutch tourist flew a drone over Yellowstone National Park’s resplendent Grand Prismatic Spring. Unfortunately, the drone crashed into the 160-degree-Fahrenheit waters, where it remains today. The National Park Service banned drones from parks in June, and as a consequence the pilot, Theodorus Van Vliet, has been charged with $5,000 in fines and/or six months in jail and/or five years on probation. Under the same policy, the National Park Service has charged at least two another drone pilots.

Ram Versus Sky Cam

While the National Park Service is worried about drones hurting wildlife, perhaps it’s the drones that should fear the animals. In the below video, YouTube user Buddhanz1 flies a drone in search of a ram, and the ram headbutts the quadcopter right out of the sky. Watch the video:

Red Skies

At the Peace Mission 2014 exercises, forces from China, Russia, Tajikistan, Kazakhstan, and Kyrgyzstan all worked together in trial counter-terror practice. Together with absent member Uzbekistan, these countries form the Shanghai Cooperation Organization. Together they tested normal operations incorporating drones. From our story:

Perhaps the most high profile Chinese weapon was the use of a Pterodactyl UCAV, considered the equivalent of the US MQ-9 Reaper, which bombed an enemy "terrorist" target with an ATF-10 ATGM.  The usage of a UCAV in what was actually a fairly conventional mechanized operation is something not yet well integrated in American operations of the equivalent aircraft. It also suggests that Chinese doctrine may be more risk-friendly in employing unmanned platforms against well-armed opponents than American drone use has been so far.

Drone Home

A local news station reports that a University of Texas student flew a drone over the university’s first home game. Police detained and questioned the student, but the murkiness of drone law leaves it unclear whether there's an existing law the student violated.

Did I miss any drone news? Email me at kelsey.d.atherton@gmail.com.

Plastic Microparticles Found In Beers

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Contaminated brewski
Examples of microplastic contaminations in German beers. White arrows indicate non-stained synthetic material.
Gerd Liebezeita & Elisabeth Liebezeita

Beer lovers: there may be more to your brew than dazzling citrus overtones or a subtle chocolatey aroma.

The authors of a new study went to a local supermarket in Germany and picked up 24 brands of beer, including the 10 most popular in the country. In the lab, they found plastic particles and other debris in everything they tested. The study was part of a larger investigation of plastic microfibres that are turning up all over the natural world as larger plastics break down. (In June, Illinois became the first state to ban plastic beads in cosmetics, which are thought to be one source of the pollution.)

How the plastic ended up in beer is an open question. The paper notes than some of the brands claim to use only spring water in their products, and sand particles often found around springs also showed up under the microscope. Malfunctioning equipment, unclean bottles, and even contaminated barley and hops are all possible sources. Beer may be filtered with activated charcoal, asbestos, wood chippings and other materials that could carry plastics.

The study only gets more shudder-worthy when it turns to the other debris they found.

"Workers in breweries lose, as any other people, the outer part of their epidermis," they write.

Scales of exfoliated skin were found in both small and larger chunks, along with bits of glass and even an "almost complete" dead insect.

Other filth
Non-synthetic particles in beer: (A) insect remain, order Thysanoptera; and (B) glass shard. Scale = 3.1 mm.
Gerd Liebezeita & Elisabeth Liebezeita

The study concludes that none of the samples contained enough plastic or other materials to present a danger to the public. The important takeaway, the authors write, is that if these tiny plastic bits are making it into beer, they have penetrated the human environment.

The Week In Numbers: Radioactive Boar, Homemade Theremins, And The 200 MPG Motorcycle

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Tanks participating in the China-based anti-terrorist exercise.
sina.com

7000: Number of Chinese, Russian, Kyrgyzstani, and Kazakh troops deployed for Peace Mission 2014.

7: Hours an average toddler spends in front of a television every day.

17: Phony cell towers Cryptophone customers detected across the United States in July. 

80-90 leaks/hour: The rate at which your Samsung Galaxy SIII sends data to parts unknown.

Less than 1 percent: Portion of this transgenic silk vest and scarf made up of spider proteins. Added strength? 53 percent.

0.4 Percent Spider Silk, 99.6 Percent Silkworm Silk
Yoshihiko Kuwana et al., PLOS One, 2014. CC BY 2.5

200 MPG: Fuel economy of this aerodynamic motorcycle. It'll run you $5,000 though.

Allert Jacobs' Aerocycle
Hans Pieterse

35: The number of years a megadrought might last in the American Southwest. Odds of that happening? 50 percent.

12: Number of homemade theremins at the NYC Makers show.

Bitty Synth
The modules created by littleBits can be combined to form a variety of electronics projects—including the turntable-based synthesizer shown here.

$1: Minimum cost of a ticket in Mars One's space raffle fundraiser.

$1 trillion: The national student debt burden.

297 out of 752: Number of boar in Saxony, Germany carrying unsafe levels of radiation more than 28 years after the Chernobyl disaster.

700: Distance in miles between Saxony and Chernobyl. Those radioactive particles traveled a long way.

Wild Boar

11: Number of cadavers used to determine how your gut bacteria move through your body when you die.

100: Years since the death of Martha, the world's last passenger pigeon.

Passenger Pigeon Exhibit
Wikimedia Commons

3: Number of people in France who received a direct brain-to-brain message over the Internet from one person in India.

Receiving a Brain Message
Carles Grau et al., PLOS One, 2014. CC BY 2.5

Your Vote Can Give This Electric Racecar Driver A Big Speed Boost

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Formula E Racecar

KatherineLegge.com/Amlin Aguri

In the April 2014 issue of Popular Sciencewe exploded the view of the racecar designed for Formula E -- the first fully electric, global racing championship. Back then the first round seemed so distant. But now drivers are only a week away from hitting the track inside shockingly quiet vehicles that can top 60 mph in about 3 seconds.

One of those drivers is British auto racer Katherine Leggethe first woman confirmed for Formula E. Popular Science is happy to report that we've partnered with Legge for her inaugural race -- which means we’ll be going along for the ride. At the launch of the Formula E series in Beijing on Saturday, September 13, Legge's helmet will be emblazoned with our logo as she competes against 19 other drivers. She also plans to post exclusive, on-the-ground reports here at PopSci.com. (Look for those starting next week.)

Why are we fans of Legge? Because she’s a fan of science, technology, engineering, and mathematics. For example, Legge is a STEM ambassador for the Girl Scouts to remind young girls that they can succeed in any field if they work hard and believe in themselves.

We couldn’t agree more, which is why we’re hoping to give Legge a little extra boost out on the racetrack. And that's where you come in.

Formula E gives its fans an unprecedented chance to help out a driver through a system called FanBoost. In short, the three drivers with the most votes from registered fans get more speed. More specifically, they each get a 5-second, 30-kilowatt boost, ramping up their cars' 150 kilowatts of power to 180 kilowatts just before the race begins.

Fans can vote for only one driver, and voting closes on the day of the race. So be sure to cast yours before September 13. (Go Legge, go!)

Visit FanBoost to give Legge a leg up on the track.

Hero Shot
Katherine Legge stands in front of her Formula E racecar.

KatherineLegge.com/Amlin Aguri

Colorful Earthquakes, Enormous Superclusters, And Other Amazing Images Of The Week

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A Sizeable Supercluster
Our celestial home just got a whole lot bigger -- on the astronomical map, at least. This week, a team of astronomers re-charted the supercluster of galaxies that includes the Milky Way, finding it to be 100 times bigger in volume and mass than previously thought. In a new study, published in the journal Nature, the researchers chronicled the motions of the galaxies, in order to determine the “gravitational landscape” of the local Universe. The team named the enormous supercluster Laniakea – Hawaiian for “immeasurable heaven."
Nature


Can We Hack Our Vision To See Infrared With The Naked Eye?

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With normal vision, you couldn't see this foliage at night. With infrared vision, it comes at you in full color.
Dan Bracaglia

“Can you imagine a color you’ve never seen?” Jeffrey Tibbetts asks, looking directly into the Skype camera. We would like to think that we can, of course, that our imaginations are limitless. But the answer, no matter how much we skirt around it, is actually “no.” However, Tibbetts insists that he himself can see another color. He, along with several friends, is part of a homegrown experiment where he has attempted to alter his vision to see in the infrared, which humans can’t usually see. The three experimenters have just completed a 25-day nutritional regimen and, as their bodies return to normal, they will continue to document their vision for the next two weeks. Very early results appear promising, albeit incomplete. But several experts in ophthalmology have doubts about the purpose and safety of the project, not to mention the validity of the results themselves. 

People who want to improve how humans function span the full range of invasiveness, from gym rats who chug protein shakes to biohobbyists slicing open their flesh in basements. Tibbetts and his co-experimenter, Gabriel Licina, are solidly in between. The team spent six months reviewing previous studies to craft a nutritional protocol designed to modify their vision, bearing the mark of their backgrounds in human anatomy and molecular biology. But their acceptance of the risks reflects their rogue scientist attitude; test subjects who don't follow the protocol, either through wrong vitamin dosage or improper diet, could go blind.

“I’ve always been interested in the ways we can enhance human beings, and the most available is pretty much our sensory systems,” Licina said. So the two began to study the literature on how to see in the infrared. Before the ubiquity of infrared goggles, military research projects dating back to the 1930s tested infrared vision in rats. After six months of research, Tibbetts and Licina decided on a tactic: regular doses of a vitamin over a series of months with the aim of letting their eyes make sense of light in longer wavelengths.

The rods and cones in our eyes allow us to see the range of colors that we do. Rods help you see when there’s not much light (and not so well in color), and the three different types of cones are sensitive to overlapping yet very different wavelengths, so we can see in the full range of colors. A dietary compound called retinal, a form of vitamin A,  binds to enormous proteins called opsins in the eye, which convert light into a chemical signal that your brain can interpret. When a photon hits the retinal, a chemical reaction takes place at the end of the appropriate cone in your eye. And, in just a few milliseconds, you’re seeing in color.

Licina and Tibbetts planned to override this function by replacing their regular consumption of vitamin A (found in dairy products and some vegetables) with vitamin A2, a version of vitamin A that humans don't typically consume. The experimenters kept a strict diet for 25 days, mixing in a dose of A2 to a powdered dietary supplement and drinking it throughout the course of the day to ensure they consumed no vitamin A (they were also allowed a few foodsdevoid of vitamin A, like peanuts and white onions). The experimenters hypothesized that increased A2 might lower the range of wavelengths that these cones can absorb, extending from visible light down into the infrared spectrum. But the protocol also had some unexpected side effects, like reduced appetite and emotional instability, Licina said. 

The experts I spoke to are skeptical that this protocol could have its intended effect on vision. Jim Ver Hoeve, a senior scientist in the Department of Ophthalmology at the University of Wisconsin in Madison, doesn't think it could work at all: “[Tibbetts and Licina] are saying that if they get a different form of vitamin A that it can alter the photoreceptor characteristics—which they’re not going to alter." The A2, he said, wouldn't have any effect on the wavelengths that the photoreceptors can absorb. "Their experiment blurs on insanity."

A person runs other risks in eliminating or changing dietary vitamin A, too. “We see people with vitamin A deficiencies all the time and they are very visually impaired,” said Ver Hoeve. “They can’t see in the dark, the longer [the deficiency] goes on they can’t see in the light.” And the effects can sometimes be irreversible, from weakened immune systems to even death. But Tibbetts and Licina don’t see it as a problem, at least for the 25 days of their experiment. “We’re talking about deficiency for upwards of a year,” Tibbetts said. “Until you get really far down this path, your vision would return within days [when you consume vitamin A again].”

But not all experts are as critical. "It seems entirely conceivable," said Benjamin Backus, an Associate Professor at the Graduate Center for Vision Science at SUNY College of Optometry in New York City. “If you took out vitamin A and replaced with A2, you could lose the ability to see blue [which has short wavelengths]. Or you might have a transition period where you’d respond to a larger range, but the cost would be some loss of sensitivity within the old range.”

After six months of studying the literature to develop a nutritional system, Tibbetts and Licina (along with 5 other experimenters) put their protocol to the test—on themselves. They also orchestrated a successful crowdfunding campaign, necessary to buy the vitamin A2, which costs about $1,000 for a fingernail-sized drop of oil. The experimenters took 1.6 milligrams of oil every day, about $25. “We realized that our allowance money and pocket change weren’t gong to cut it,” Licina said.

To test whether their eyes were really absorbing infrared light, the experimenters created a electroretinograph (ERG), a small box that a person puts over her eyes that flashes LEDs at different wavelengths. The experimenters modified the ERG, which is open-source on the Internet, to only flash light in infrared wavelengths, longer than 730 nanometers (visible light ranges from 400 to 730). The system wasn’t perfect—“there’s some bleed” between the different wavelengths, Tibbetts admitted—but the charts the team posted online showed that their eyes were responding to light in the infrared wavelengths just below the visible spectrum, around 950 nanometers:

These charts of ERG response, posted by the experimenters on their project's web site, show that the eye responds to light at 850 and 950 nanometers, wavelengths that normal eyes presumably would not be able to see.
Science for the Masses via experiment.com

Licina and Tibbetts hope to get their study published in a reputable journal, but Ver Hoeve of the University of Wisconsin had some concerns about their methodology. “Those ERG measurements would never be published in a journal,” he said, mostly because they lack information to make them repeatable, like how often the measurements were taken. Ver Hoeve is also concerned that the experiment had no control, an ERG from someone not taking the vitamin A2. But Licina himself, who was not taking the vitamin A2, gave the base-level readings for comparison. "We also have reading from pre-vitamin and are taking some now post supplementation," he said. 

For SUNY’s Backus, who is more optimistic that the experiment will be successful, the lingering question is the reason for all of this. He himself has spent days on end in utter darkness to test a treatment for amblyopia, a childhood disease that can cause adult blindness. “So I’m not averse to trying wacky things that are high risk and high reward, but I don’t know what the reward here would be,” he said. “Getting a cool visual effect is not a sufficient benefit to outweigh the cost.”

But to Tibbetts and Licina, their project looks different. They wanted to push the boundaries of human capabilities, like many before them, but they wanted to also demystify the scientific process behind it. “We wanted to be able to do science without the restriction you get working in an academic setting,” Licina said.  “If we don’t get it published, we’ll open-source-license it on the Internet,” Licina said. “This is really cool research that should be accessible to everybody.” They worked to make their nutritional protocol comprehensible, although not all of the test subjects were able to follow it; of the six experimenters who started the protocol, only three lasted more than two weeks, dropping out because other things mattered more to them, like socializing over meals. “As long as you follow the rules, anybody can do it,” Licina said. Although Backus said he wouldn’t do the experiment himself and would have serious ethical concerns bringing it to a college review board, “I can’t in good faith to tell someone who wants to do this not to do it,” he said, as long as the subjects are properly monitering their health and looking out for signs of vitamin A deficiency. 

For those not ready to try the protocol themselves, the biohackers' descriptions of infrared vision will have to suffice: “Anecdotally, subjects are seeing strange reddish colors, losing blue/green definition, and have been pointing out things in the dark to others who can't see them at all,” Licina said.

To see the final results of Tibbetts and Licina’s experiment, visit their experiment page

NIH Lab Search Yields 100-Year-Old Ricin Sample

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photo showing a woman reaching into a refrigerator full of boxes
Biological samples in a freezer.
Nick Smith/ALSPAC via Wikimedia Commons

Remember last week when the U.S. National Institutes of Health asked American scientists, "Pls check yer vials!"? (We're paraphrasing.) Apparently, the agency has taken its own advice to heart. In a search of its own facilities, they found forgotten bottles containing ricin--a potent poison--as well as vials of organisms that cause botulism, plague and other illnesses, the Associated Press reports. The ricin sample is estimated to be 85 to 100 years old.

The AP reports the NIH sent out a memo saying the vials were all found sealed and intact. That suggests there's nearly no risk anybody could have gotten sick from them. Still, the discovery underscores the likelihood that labs around the U.S. and the world are holding onto dangerous biological agents without knowing it.

The NIH launched its agency-wide freezer search after federal scientists discovered forgotten vials of smallpox virus in a Food and Drug Administration lab refrigerator in July. Since the start of the campaign, officially called National Biosafety Stewardship Month, federal labs have undergone elaborate-sounding searches. The White House Office of Science and Technology Policy also sent out a memo to university scientists, asking them to participate. There's no legal mandate to participate, but perhaps the NIH's discoveries will spur them to.

NIH scientists destroyed the antique samples they found, the AP notes.

Why Am I Afraid Of Hugh Jackman?

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Hugh Jackman
20th Century Fox

A reader recently wrote to Popular Science asking for advice on a... unique problem:

"I have a severe fear of Hugh Jackman. Are there any special methods for expelling the fear? My friends tried to take me to see his new movie to help, but it didn't help on any level."

First suggestion? Maybe find some new friends.

In the fictional world, a dread of Jackman makes sense. His every adamantium movement carries the threat of roaring muttonchopped vengeance. Soon he'll play the bloodthirsty pirate Blackbeard in Pan, due out in 2015. Back in reality, however, people gravitate toward his A-list celebrity status and muscular physique, making it hard to understand why anyone could fear his visage.

For a little help, we called Martin Seif, psychologist and author of What Every Therapist Needs to Know About Anxiety Disorders: Key Concepts, Insights, and InterventionsHe tells Popular Science that the difference between a healthy fear and clinical phobia is not logic. Instead, it all depends on if the fear is far more extreme than the actual danger--and Jackman seems like a nice guy by our reckoning, even if he can deadlift 400 lbs with ease.

Seif says that specific events rarely lead to developing a phobia. When they do, the fear is often just one small part of Post Traumatic Stress Disorder, a broader illness. Phobias do, however, tend to run in biological families. So while a traumatic screening of Les Misérables would be a highly unlikely cause, our reader's brain might have been primed with the potential for fearing Jackman all along.

Oh good.
Warner Bros.

Seif says the fear of the panic that our dear reader might feel around Jackman--a sort of "phobophobia"--likely plays a bigger problem than the terror itself.

Maybe the reader has experienced the fear as long as he or she can remember (as is usually the case with animal fears like arachnophobia), and has trained to avoid triggers. Or perhaps, like many adults who develop anxiety about enclosed spaces or flying, the phobia developed later in life. Seif says the latter type of sufferers, who are less accustomed to having an episode, can feel sick and think something is wrong with their bodies.

"They all basically have the same question," he says. "'Can you turn off my mind?'"

Whether it's addressing a fear of Jackman or clustered holes, the most common technique for curbing phobias calls for staying in the moment. "Anxiety always starts with a what-if catastrophic thought," Seif says. Some psychologists feel that mindfulness and breathing exercises can also help sufferers avoid having an episode of immobilizing fear.

The problem, Seif says, is that the more someone with a phobia tries to stay in the present, the likelier he or she is to worry about the future. So a more modern approach teaches patients not to stave off the sirens in their heads, but to recognize them for what they are: bad signals from the amygdala, a brain region greatly associated in feelings of fear. "There's more pain in avoidance," Seif says. "The key is to be less afraid of the false alarm."

One final response to our reader's letter, even if it's only a ploy to see the first-ever article dedicated to a fear of Hugh Jackman: According to Seif, highly specific phobias, such as a fear of a celebrity or the color blue, are rarely true anxiety disorders. Instead, they're often expressions of obsessive-compulsive disorder, which is a different disease with differenttreatmentregimes.

Whatever ails you, our best advice is to seek the help of a trained and licensed professional--not an email address scanned by Popular Science interns.

Flight MH-17 Investigation Points To An Attack

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Investigation Of MH-17 Crash Site
Investigated here by Dutch and Australian police officers
Netherlands Ministry of Defense, via Wikimedia Commons

On July 17th, Malaysian Airlines flight MH-17 from Amsterdam to Kuala Lumpur fell out of the sky over eastern Ukraine. The crash killed everyone on board the plane, including 15 crew members and 283 passengers. Today, less than two months after the fact, the Dutch Safety Board published their preliminary investigation into the crash. Their findings strongly reinforce evidence that a sudden attack destroyed the plane in mid-air, sending it crashing into farmland in the middle of a civil war below.

What happened to the plane?

It’s very likely that something hit it from outside. This is supported by examination of the wreckage, and a lack of evidence for other problems.

The wreckage from the plane was found in an area approximately 3 miles wide by 6 miles long. The wide spread of the plane parts is a sign that the plane's breakup happened in the air. While some major wreckage components have not been recovered, visible evidence is consistent with an attack from outside. From the report:

Photographs from the wreckage indicated that the material around the holes was deformed in a manner consistent with being punctured by high-energy objects. The characteristics of the material deformation around the puncture holes appear to indicate that the objects originated from outside the fuselage.

The report specifically states that there’s no indication that internal problems, either mechanical failure or poor plane operation, caused the crash. Instead:

The damage observed in the forward section of the aircraft appears to indicate that the aircraft was penetrated by a large number of high-energy objects from outside the aircraft. It is likely that this damage resulted in a loss of structural & integrity of the aircraft, leading to an in-flight breakup.

Were There Signs Of Trouble?

Preliminary Flight Recorder Data
The lines all end suddenly, though because they record data points at intervals ranging from 8 times a second to once every 4 seconds, they don't end at exactly the same spot.
Dutch Safety Board

By all appearances, and the data published in the preliminary investigation, there was nothing unusual about MH-17’s flight until it suddenly stopped at 4:20pm, Ukrainian local time.

The black box audio recorder showed no signs of tampering, and the black box audio recording "ended abruptly," according to the report. "A replay of the [recording] did not identify any aircraft aural warnings of alerts of system malfunctions.”

As this is a preliminary report, there’s still more to analyze, but it helps to refute an unusual theory about the crash. Ukraine is currently fighting a war against Russian-backed separatists in Eastern Ukraine, and they’re using Su-25 ground attack planes as part of that fight. Repeated by Russian state media, the theory holds that a Ukrainian Su-25 flew within range of MH-17, and then shot it down with an air-to-air missile. The Su-25 can’t fly as high as MH-17 was when it was hit, and now evidence shows that the airliner pilots didn’t mention seeing anything unusual, like a nearby fighter jet.

What’s Left Unanswered?

The report doesn’t name the specific weapon that brought down the plane, leaving the explanation at “large number of high energy objects that penetrated the aircraft from outside.”

Other evidence from the crash points to a Soviet-designed Buk missile as the culprit. The day MH-17 went down, Ukrainian interior minister, Anton Gerashenko attributed the crash to a Buk missile fired by separatists. Three separate eyewitnesses told BBC Panorama they saw a Buk missile launcher in the area in the hours before the crash. The citizen investigative journalism site Bellingcat used photographs and videos from locals to trace the July 17th path of the missile launcher in Eastern Ukraine. Matching license plate numbers and vehicle markings, Bellingcat also claims to have traced the specific Buk missile launcher back from Donetsk to Russia.

Print, Assemble, Drive: The 3-D Printed Plastic Car

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illustration showing a squat black and red car
Design for the 3-D Printed Strati Car

In a convention center in Chicago, there's a living-room-sized 3-D printer that's just finished printing the parts for a driveable plastic car. The engineers working on the car -- including those involved in developing the plastic, the printer, and the car design -- are hoping to have something ready to drive off the premises by the end of the week.

Here's a Vine of the car print, made by Local Motors, one of the car's developers::

The printer is the world's first large-scale 3-D printer that works with polymers, Oak Ridge National Laboratory engineer Lonnie Love told the Chicago Tribune. Oak Ridge worked with a company called Cincinnati Incorporated to develop the printer. "It builds some of the biggest parts in the world, faster than anything else," Love said.

The car will be made up of about 40 printed polymer parts, the Chicago Tribune reports. The car's body, fenders and seats were printed; the motor, tires and suspension were made more conventionally. Now that all of the polymer parts have been printed, engineers will sand the printed pieces smooth and assemble the car over the next week.

The car model is called "Strati." Phoenix-based Local Motors is hoping to have Stratis ready to sell "in the months following the show,"according to the International Manufacturing Technology Show, where the printer is being demoed now.

photo of a 16-foot-long 3-D polymer printer
The Big 3-D Printer
Its official name is the Big Area Additive Manufacturing machine.
Cincinnati Incorporated

Meanwhile, Cincinnati Inc. is trying to commercialize the printer. The company has already sold two of the machines, but to a plastic company that wants it for research and development (The company wants to figure out how to formulate plastic mixes that would work in the machine). According to its website, Cincinnati Inc. is hoping to sell printers to companies that make parts for cars, aircrafts, appliances, and robots. A large machine like this would allow companies to print bigger-than-ever pieces -- up to 10 times bigger than industrial 3-D polymer printers available today.

Who Owns Asteroid Rights?

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asteroid, mining, satellite, space
Concept art
Robotic asteroid mining might look like this.
Deep Space Industries

Congress is back in session and getting right down to work on pressing science and technology issues like education funding, Net neutrality and ... oh wait. Actually, the House is holding a hearing on Wednesday to discuss a new law to manage resource mining in space: the ASTEROIDS Act (PDF).

No one seems to be asserting that managing mineral claims on asteroids is a pressing issue at the moment. But as Adam Minter reports today for Bloomberg, establishing a legal framework for it would probably help spur more entrepreneurial interest in the sector. James Cameron, Eric Schmidt, and Larry Page are among the investors in Washington State-based Planetary Resources, which plans to survey the “low-hanging fruit of the Solar System” using its Arkyd series of robotic spacecraft. Planetary Resources is also behind the Asteroid Zoo project, which exploits enables students, citizen scientists and other interested amateurs to hunt for undiscovered asteroids.

Texas-based Deep Space Industries last year announced plans to survey, prospect, harvest and process water and rare earth metals via a number of CubeSat-derived space probes called (...wait for it...) “Fireflies.” Shiny!

The proposed legislation, dubbed ASTEROIDS (for American Space Technology for Exploring Resource Opportunities In Deep Space), would work with the existing legal rubric of the 1967 Outer Space Treaty, which prohibits national claims on celestial territories as well as claims by private sector entities within signatory nations. The proposed legislation would give U.S. companies ownership of any materials they mine from asteroids, although not ownership of the asteroid itself. Minter notes that it's an approach similar to current laws around claims to marine resources. 

The ASTERIODS Act will need tweaks, however, to create a solid foundation for space mining once firms from different nations get into the act. There's a precedent for this too, Minter notes, “in U.S. law related to mining of the deep-sea bed (also a field that’s more speculative than real at the moment).”

Rather than accept an international authority to regulate such activity (under the United Nations Convention on the Law of the Sea, or UNCLOS), U.S. law since the early 1980s has made provision for reciprocal recognition of deep-sea claims. In the mid-1980s, the U.S. extended reciprocity to the U.K., Japan, France and several other countries with similar laws.

As applied to space, these agreements would not only offer long-term property assurances to space prospectors (and perhaps attract a broader range of international investors) but also represent a small but important step forward in building trust and perhaps even encouraging global collaboration in space ventures.

The ASTEROIDS Act is co-sponsored by Representatives Bill Posey (R-Fla.) and Dered Kilmer (D-Wash.). The Sept. 10 hearing before the Space Subcommittee of the House Science, Space, and Technology Committee begins at 10:00 am ET.

Lawmakers – and those watching via the livestream - will hear from a panel featuring experts from NASA, the National Research Council, The Planetary Society, and the Journal of Space Law.

Augmented Reality Visor Will Overlay Data On The Real World

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Terminator Vision
Orion Pictures

Playing a first-person shooter like Call of Duty with a virtual reality headset like the Oculus Rift or the Sony Morpheus seems like a recipe for ultra-realistic gaming bliss – until you sprint after virtual Germans and plow right into your actual living room wall.  

When you wear a screen on your face, “there’s a lack of situational awareness of the actual world,” says Leap Motion co-founder Michael Buckwald, sipping a soda at a demo at the company offices in San Francisco.  “Also, every time I want to take a sip of Coke, I have to take the Oculus Rift off.”

“In a first-person shooter, you need to be able to turn around quickly,” says Omar Khan, the lead Unity developer at Austin-based Chaotic Moon, which designed a humorous Oculus Rift game called Shark Punch.  “And if you're sitting in a chair, tethered to a computer, it's very difficult to be able to turn.  And to aim -- it's very awkward, it's kind of weird.”

The system gives a user full awareness of the real world while immersed in a virtual one.

Leap Motion has announced new hardware and software for its infrared controller, which allows users to interact with computers using just hand and finger gestures. (Popular Science profiled the original Leap Motion device in 2013).  When paired with a virtual reality headset like the Oculus Rift, the system gives a user full awareness of the real world while immersed in a virtual one.

The Oculus Rift headset, acquired in March for $2 billion by Facebook, offers stereoscopic 3-D and 360 degree visuals, for a richly experienced virtual world.  But as far as seeing the real world, wearing one is like strapping a bucket on your head.  Leap wants to become the go-to controller for VR.  The company’s just-announced tweaks include a clip-on mount for VR headsets like the Rift, and improved “top-down” tracking of the hands, even when the user reaches out or turns around.

Developers like Khan have experimented with using the gestural interface on the first-generation Leap controller to manipulate the Rift’s virtual reality, attaching the hand-detecting infrared Leap sensor to the front of the Rift headset, sometimes with duct tape. For first-person shooter games, where players hold a weapon, this can feel awkward, because the user must hold the hands high up, in front of the sensor, for proper tracking. The new top-down tracking orientation, clip-on mount, and larger field of vision will make gesturing for the sensor more comfortable.

Most importantly, Leap has released an application programming interface (API) that will essentially turn the device into a 3-D camera, by letting programmers access infrared data about the user’s surroundings.  Using this API, raw infrared imagery of the real world can blend with a representation of the virtual realm.  This is a crucial milestone on the way to true augmented reality.  

Leap VR
courtesy Leap Motion

“We're able to take the live feed of what [users] see and convert it on the fly into a virtual world,” says Khan.  “That is something that is quite different.”

Google Glass bombed with many early adopters because it was essentially a “phone for your face” that did nothing more than display output from conventional apps.  The new API will incorporate the room into the game.  This is true augmented reality.

Medical students might take nanoscale walking tours of the brain.

“Let's say we wanted to create a game where we create creatures that come out of the environment around us, like my office,” says Khan.  “Because of the ability of [the new API] to give you raw image data, you could make a tree grow right in the middle of your office.  Or, if you want enemies to come spawning at you, there's your desk, and all of a sudden, there's this goblin in your desk.  So there's a lot of things you can do that haven't been seen before.”

Medical students might take nanoscale walking tours of the brain.  Or high schoolers might go on intergalactic journeys.  The ability of the device to track tiny .01 millimeter finger motions, far finer than those by the Microsoft Kinect, permits sculpting of 3D virtual objects that might give rise to a new generation of claymation artists.  

But in the short-term, virtual reality will sink or swim with gaming.  Khan thinks game studios will be attracted by the possibility of doing something entirely new.  After all, in theory, the raw-image data will allow you to turn your ordinary living room into the infested space station from Aliens.

“We know that our office looks like this, has a wall over here, but we want to render something from Aliens.  We could do that.  Or you could create a Nerf battle virtually, or a paintball game virtually, in your office,” Khan says.  “Everyone is walking around Oculus Rifts and Leap Motion cameras, pulling data from where they're at.”

These games can get gamers off their behinds in a far more elaborate way than with the Wii or the Kinect, because you’re no longer tethered to your T.V. or to your same-old surroundings.


Multicolor Map Shows Differing Regions Of Rosetta’s Comet

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Crossing State Lines
Each indicated region reveals a morphologically different area of 67P.
ESA/Rosetta/MPS for OSIRIS Team
On August 6, the European Space Agency’s Rosetta spacecraft arrived at Comet “67P/Churyumov-Geraskimenko,” making it the first vehicle to reach and orbit an asteroid. Ever since, the two bodies have been engaged in something of a cosmic dance, moving in sync with one another as Comet 67P’s elliptical orbit brings it closer to the Sun.

The celestial tango is only temporary, meant to give Rosetta time to figure out the right place to land on the oddly shaped rock (sometimes lovingly referred to as the Rubbery Ducky comet). But in the meantime, it has also afforded the spacecraft with a unique opportunity: getting some really killer photographs of an asteroid. OSIRIS, Rosetta’s scientific imaging system, has taken a number of high-resolution images of 67P since its arrival, and they reveal the comet to be a truly multidimensional world.

Now, scientists at the Max Planck Institute for Solar System Research have plotted the different regions of 67P, making a multi-colored map that looks something like Pangea (or a psychedelic human heart). Each area is defined by unique morphological characteristics, meaning the comet has a multitude of different terrains. Cliffs and boulders dominate some regions, while others house large depressions, craters, and even parallel grooves. Many of the areas are quiet, while others are shaped by the comet’s activity in space.

According to the Max Planck researchers, the map is made possible given the “unprecedented resolution” of the photos. “Never before have we seen a cometary surface in such detail,” says OSIRIS principal investigator Holger Sierks. In some of the OSIRIS images, one pixel corresponds to 75 centimeters in scale. Dang!

As 67P and Rosetta near the sun, scientists will continue to monitor the comet’s surface for any changes. Though they don't expect much activity, subtle transformations in the surface could help the researchers better understand just how the comet morphed into the complex world it is today.

Variety Is The Spice Of Life
In this image, the variety of different surfaces on 67P can be seen.
ESA/Rosetta/MPS for OSIRIS Team

Crops Grow On Fake Moon And Mars Soil

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Conceptual Rendering Of A Greenhouse On Mars.
Maybe greenhouses on Mars wouldn't have to be hydroponic after all.
NASA
If humans ever set up permanent bases on the Moon or Mars, we'll need to be able to grow our own food there. To find out whether that’s actually possible, a team of scientists in the Netherlands planted 14 plant species in soils that simulate the Martian and lunar regolith. It turned out that the Martian soil simulant was better than some Earth soils for growing plant life, which is good news for astronauts. There are a few caveats, but we’ll get to those later.

First, you’re probably wondering what the heck is a soil simulant, and where does it come from? NASA makes them out of our very own terra firma, and you can buy your own here. (Cost: $7.50 for 2 ounces.) The Mars simulant (PDF) comes from a volcanic cone in Hawaii, and has a chemical composition similar to the Mars dirt that the Viking 1 lander analyzed. The Moon simulant (PDF) comes from volcanic ash deposits near Flagstaff, Arizona.

Real Moon and Mars soils appear to contain the essential ingredients that plants need, except for reactive nitrogen (and an abundant water supply). Though the simulant soils closely match the composition and grain size of the real stuff, they also contain trace amounts of the nitrates and ammonium—the nitrogen-based compounds that plants love. So the simulant soil isn’t a perfect model. 

For their experiment, the scientists ordered piles of fake Mars and Moon soil, then scooped them into small pots and planted 14 different species inside -- including carrots, tomatoes, wheat, some common weeds, and four species that turn atmospheric nitrogen into plant food. The scientists also planted seeds in some nutrient-poor soil that they dug up from 30 feet below the river Rhine, for comparison. All in all, they planted 840 pots.

Other scientists have attempted to grow plants in lunar and Martian soil simulants before, but this study appears to be the largest and most extensive to date. And the results were promising. Most of the crops were able to grow on all three kinds of soils. In fact, many thrived better on the Mars simulant soil than the poor river soil -- both in terms of the number of plants that germinated, flowered, and survived to the end of the 50-day experiment, as well as in terms of the total biomass that grew from each pot.

Plants fared worse on the lunar soil. None of the leopard’s bane or field mustard survived to the end of the experiment. Common vetch, a nitrogen-fixing plant, didn’t even germinate. That suggests to the researchers that lunar farmers may need to inoculate the regolith with nitrogen-fixing bacteria instead. That, or use human feces as a manure to provide right kind of nitrogen.

“Our results show that in principle it is possible to grow crops and other plant species in Martian and Lunar soil simulants,” the researchers write. “However, many questions remain…” such as how much water can the soils hold (because the ones in this study seemed to dry out pretty quickly) and how do gravity, light, and other conditions on other worlds affect the plants’ ability to grow?

The study was published in the journal PLOS One.

Your Robot Chauffeur Has Arrived

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NAO in BMW
teeny, tiny BMW
RobotsLAB

Not so fast, driverless cars. In the future, we might combine the aristocratic with the automated in a robotic chauffeur. This combo pack of Nao robot and electric BMW  is available to drive you around for $9,990, provided you can fit into a tiny electric BMW, and you're willing to teach the robot how to drive it.

Nao is a companion robot that responds to verbal commands, first made in 2006. The robot can see with cameras, recognize voices, communicate over both internet and infrared channels, and can be programmed in C++, Python, Java, and other languages. This last bit is important: the Nao BMW is touted as a learning tool for schools and students that want to get ahead in science, technology, engineering, and math. The BMW comes with a laser rangefinder, autonomous driving, and obstacle avoidance built in.

Watch Nao drive his blue BMW around some pedestrians below. It’s neat, but it’s still no robot on a hovercycle.

The Perpetual Potential Of Nuclear

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The May 1947 issue of Popular Science
We have entered the lair of the atom, God help us, and the door is locked behind us. There is only one way to go.

In May 1947, Popular Science looked back on 75 years of scientific progress. Though fewer than two years had passed since the world witnessed the bombings of Hiroshima and Nagasaki, scientists foresaw a new era of clean, reliable energy from the same destructive source: nuclear power. In 1951, the Experimental Breeder Reactor I near Arco, Idaho, became the first nuclear plant to generate electricity, powering lights in the testing area. More recently, disasters at the Chernobyl and Fukushima plants triggered backlashes that stifled the expansion of nuclear power in Western countries. Nowadays, Western countries are decomissioning more reactors than they're building. China and Russia, by contrast, are investing heavily in nuclear power.

Milestones in Nuclear Power

100 kW First usable amount of electricity produced by a nuclear power plant near Arco, Idaho, in 1951

10 MW Capacity of the USS Nautilusthe world’s first nuclear-powered submarine, in 1955

20 MWPower output of Calder Hall A in England, the first reactor for large-scale commercial production, in 1956

8,212 MW Net electricity produced by the world’s most powerful nuclear-power plant, in Japan, since 1997

This article originally appeared in the September 2014 issue of Popular Science.

Meet Germanene, Graphene's Newest 2-D Competitor

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scanning tunneling microscope image of germanene's atomic structure
Under the Microscope
A scanning tunneling microscope image of germanene
M. E. Dávila et al., New Journal of Physics, 2014

Guy Le Lay says he's working his way down the periodic table. In 2012, he was the senior scientist on a research team that was the first to prove it had created silicene, a one-atom-thick array of silicon atoms. Silicene is the silicon equivalent of graphene, which is a flat array of carbon atoms with a number of potential applications in super fast computing. Silicon also happens to be just below carbon on the periodic table. Now, Le Lay and his colleagues are publishing evidence that they've made germanene, a material made of a single layer of atoms of germanium, the next element down the list.

The report from Le Lay, a professor emeritus of nanotechnology at the Aix-Marseilles University in France, comes just a month after a Chinese team became the first to create germanene. The coincidental publishing highlights the work scientists have put into making two-dimensional materials.

Researchers who study 2-D materials hope that they can one day be incorporated into next-generation transistors or even quantum computers, both of which have promise to overcome silicon's physical limits and make future computers faster. Silicene and germanene are expected to have unusual electrical properties, the way graphene does. For example, electrons are expected to move across their surfaces at extraordinary speeds, the way they do across graphene.

illustration showing purple balls arranged in hexagons over gold balls
Picture This
This illustration shows the arrangement of germanium atoms (purple) in germanene. The golden atoms in the background represent germanene's gold substrate.
M. E. Dávila et al., New Journal of Physics, 2014

It's hard to know which material will win out in the computers of our future. Graphene? Germanene? Tinene, a 2-D array of tin atoms, which Le Lay wants to make next? (Yes, tin is the next element underneath germanium.) Every 2-D material has its own strengths and weaknesses. Germanene and silicene have natural bandgaps, a quality necessary for transistors, while graphene does not. Graphene has been studied far longer, however, so engineers are better at manufacturing it. They've already tried making transistors with graphene, using workarounds to deal with its lack of bandgaps.

Meanwhile, simply making germanene and silicene is a feat. The discovery and characterization of graphene was an exciting and important piece of science, but at least graphene was easy to create. Carbon atoms often naturally take on the hexagonal, "honeycomb" arrangements that characterize graphene, silicene and germanene. On the other hand, atoms of silicon and germanium don't like arranging themselves in this way. Before some recent theoretical work, chemists thought silicene and germanene couldn't exist, Le Lay says.

To force atoms of silicon and germanium to bind to each other in flattish hexagons, engineers heat the elements into a vapor, then condense the vapor onto a metallic surface. For germanene, the Chinese group condensed their germanium vapor onto a platinum substrate, while Le Lay's group used a gold substrate. After that, for the materials to be useful, researchers need to be able to take the materials off their substrates—just like a sticker isn't useful unless you're able to peel it off its backing. That step is still a subject of study, so you can imagine it will be many years yet before these graphene cousins show up in anything practical.

"I don't want to hype this too much," Le Lay says several times in our conversation. But it is really something, he thinks, that research groups have made a material that does not form in nature. "This material doesn't exist—not on Earth; not in the universe; not, probably, in the multiverse," he jokes. "God forgot to create it."

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