Indholdsfortegnelse for March 2013 i Popular Science

WHY DO WE build incredibly tall buildings? What is it in the human psyche that requires us to go higher? Is it a masculinity problem? A desire to touch God? An unholy need to see all of the Earth at once? The early-Modernist architect Le Corbusier designed, in 1922, a “Contemporary City” for three million people. Decades before the engineering was possible, he imagined a cluster of 60-story towers that would bring a metropolis together in a single vertical habitat, leaving the surrounding countryside open. It was a revolutionary idea, but it turns out that skyscrapers beget more skyscrapers, not pristine farmland, because centralizing people into vertical habitats is a matter of economics, not land management. Now architects are redefining the notion of “tall.” Supertalls, as Clay Risen describes them…

Last fall in Østerild, Denmark, the German company Siemens built the world's largest wind turbine. Each of its three rotor blades measures 246 feet—nearly the wingspan of an Airbus A380. While most turbine manufacturers make blades in two separate pieces, from molds, Siemens casts them in one piece. Because the process eliminates the need for glue, the balsa-based blades are up to 20 percent lighter than traditional ones. The reduced weight helped make it possible to build longer blades, which capture more wind and therefore generate more power. The turbine produces up to six megawatts of electricity, enough to service 6,000 households, and Siemens will install 300 in the U.K. beginning this year.…

The average smartphone today has as much processing power as a 1970s supercomputer—enough (as luck would have it) to act as the hub of a streaming home-audio network, serve as a mobile medical lab, or even run a robot. So now, instead of building robots from scratch, companies can construct models around smartphones. In the past, developing the central processing computer and software to get a robot to do even a simple task cost tens of thousands of dollars. By outsourcing brainpower, companies can cut the final price to hundreds. And since apps, not specialty code, determine how a robot acts, software developers can easily update a robot with new capabilities and behaviors. Eventually, companies may even open up their software so users can create custom robotic personalities.…

When it's finished, the New York Wheel will stand 625 feet above Staten Island, making it the tallest observation wheel in the world. It will depart from the design of other supertall observation wheels in several key ways. The 541-foot Singapore Flyer and the 443-foot London Eye, for example, are held in place by stability cables that run from their spindles to the earth. But to fit the New York Wheel on its narrow site, engineers will give it vertically oriented 320-foot-long legs anchored to the ground. For weatherproofing, engineers moved motion-control hardware from outside to inside the passenger capsules. (This will also make repairs much easier.) Construction of the $250-million project begins on-site next year. If all goes well, in 2016, passengers onboard will experience a 38-minute ride with…

“One-and-a-half million children die each year from diseases related to poor sanitation. We're building a disinfecting toilet that doesn't need running water or massive treatment plants and is cheap and odor-free. It's a squat toilet, which is what many people around the world prefer. The waste falls onto a sloped conveyor belt. Solids stick, and liquids run off into a bed of sand, which filters everything 10 micrometers or larger, including most parasites and their eggs. Then the liquid falls into a shallow trough, where an ultraviolet lamp—running on five watts from a solar panel on the roof—destroys any other pathogens in minutes. The sand filter's top layer will get clogged, so a corkscrew mechanism skims it off to join the solids, which another belt squeezes to remove moisture so…

THE ROAR OF THE CHOPPER'S ENGINES made it hard to hear. First Sgt. James Kelley signaled with his hands and yelled: “Five minutes!” In the murky light of the Chinook's cargo bay, rows of helmeted figures sat surrounded by rifles and camouflage rucksacks. It was four in the morning. Bulldog Company from the U.S. Army's 101st Airborne Division, along with dozens of Afghan National Army soldiers, forward air controllers, military intelligence officers, and bomb-dog handlers, were air-assaulting into enemy territory. Under the light of the full moon, rows of mist-shrouded grapevines and mud compounds rushed below. The mission, Operation Lion Strike, was to land in a Taliban-controlled area in one of the most violent parts of Kandahar Province, southern Afghanistan. The soldiers would then push northward, into a cluster of…

On the morning of September 11, 2001, Bill Baker, a structural engineer with the architecture firm Skidmore, Owings and Merrill (SOM), was at his office in downtown Chicago. SOM is the undisputed leader in skyscraper design, and, at least on the engineering side, Baker is its undisputed king. In the past 30 years, he has overseen or worked on six of the world's 15 tallest buildings. But 9/11 was a bad day to be king: As the World Trade Center collapsed and rumors circulated about a rogue plane headed for the Sears Tower, Baker and his colleagues watched as the symbols of their profession became objects of terror. A few days later, Baker and some of his co-workers drove to New York. The contractors at ground zero needed volunteer engineers…

Space tourism front-runner Virgin Galactic hopes to launch customers toward the edge of space later this year. To get them there, in a winged craft called SpaceShipTwo, the company will light up hybrid-fuel rockets. Hybrid-fuel engines marry two classic designs: liquid-fuel (like the space shuttle's main engines, which combine liquid hydrogen and liquid oxygen) and solid-fuel (like the shuttle's boosters, which use solid aluminum and ammonium perchlorate). Solid-fuel engines are powerful, but they burn until the fuel is gone—whether you like it or not. Pilots can throttle liquid-fuel engines, but they're very complex machines. Hybrid-fuel engines are the in-betweens. They burn solid fuel with a liquid oxidizer, which pilots can adjust, but they are far simpler than liquid-fuel engines. Learning how rocket engines work can be tricky, so wouldn't it…

Q:Does thinking too hard wear you out? SHORT ANSWER If it does, it's all in your head. LONG ANSWER The brain makes up about 150 of our body weight but consumes about one fifth of the oxygen we breathe. It's natural to assume that overtaxing the cerebrum would leave one feeling lethargic, but that's not quite true. The brain uses most of its energy just to maintain its baseline state; one tenth of our energy at rest goes to pumping sodium and potassium ions across brain-cell membranes, a simple process that keeps each neuron charged and ready. Specific mental activity, whether chatting with a friend or doing a crossword, does not suck up much extra energy. That said, studies show that people do slow down after performing taxing mental tasks.…

In August 1964, the Popular Science cover featured “stubby little Alvin,” one of a new class of submersibles designed to explore the ocean. The 22-foot-long sub had a mechanical arm and could dive 6,000 feet for up to eight-and-a-half hours. Because the steel sphere that housed Alvin's crew was only 1.33 inches thick, the sub weighed just 13 tons; it could drop its batteries and float to the surface unassisted in the event of an emergency. Alvin's first big mission, in 1966, was to search for a hydrogen bomb that had fallen into the Mediterranean Sea after a B-52 bomber crashed into a tanker during in-flight refueling. The sub's crew located the bomb in just 80 days, and a torpedo-recovery vehicle helped bring it back to the surface intact. Since…

Peter W. Singer's article on Chinese military growth [“Inside China's Secret Arsenal,” January 2013] draws a comparison to Germany out-inventing the British during World War II. Yet Singer gives no real evidence that China is likely to out-invent the U.S. That is exactly the dimension along which the Chinese system is not designed to succeed. Their low respect for intellectual property rights consistently undermines the profit motive, which is what drives meaningful leaps in R&D—whether among the Krupps of Germany or the Northrop Grummans of the U.S. Erik RichardsonMilwaukee…

Cellphone batteries once lasted a week on a charge. Today, power-hungry smartphones require daily plug-ins—sometimes more—which makes carrying adapters and hunting for outlets a part of everyday life. Engineers at Lilliputian Systems, a Massachusetts start-up, have developed the Nectar fuel cell, a portable charger that generates enough juice to power a USB-enabled phone once a day for two weeks. Unlike other portable power sources, which store energy in batteries, the Nectar runs on butane. When a user plugs his phone into the Nectar's USB port, a replaceable butane cartridge releases fuel into the cell. As fuel passes over a ceramic membrane, oxygen ions pass through the surface, which generates a current. The process can run as hot as 1,830°F, so the engineers built a network of insulating silicon-nitride tubes to…

In 1961, Claude Shannon and Edward Thorp built the world's first wearable computer. The cigarette-pack-size device tracked the speed of a roulette wheel and sent tones via radio to a gambler's earpiece to help predict where the ball would land. The goal of wearable computers hasn't changed much since. Like Shannon and Thorp's system, Google Glass and other head-up displays (HUDs)—from companies including Vuzix and Epson—are intended to heighten a person's awareness. But the latest discreet HUDs can do much more than augment our reality—they could also help us better ourselves. One of the newest methods for spurring self-improvement is to turn every task into a game. So-called gamification apps keep score in real-life situations to promote certain behaviors—whether it's taking out the trash, going for a run, or complimenting…

Scientists had never seen a spade-toothed whale; they only knew it existed because of skull fragments. Then, in 2010, a New Zealand local came upon a pair of dead whales on a beach, which rangers classified as Gray's beaked whales. But DNA tests by biologists at the University of Auckland later showed that both were the elusive spade-toothed species. When a group went last year to exhume the skeletons from the beach, the head of one was already gone. A male beluga at a research facility was making calls that sounded like a distant human conversation. So staff at the National Marine Mammal Foundation in San Diego recorded him. They found that the sound waves were several octaves lower than a normal beluga's and matched the range of human speech.…

CRITICS HAVE applauded the realism of the film Zero Dark Thirty, an Oscar favorite that claims to re-create the hunt for Osama bin Laden. But some have protested an early scene in which intelligence officers torture a man, then use the threat of further torture to persuade him to reveal a crucial bit of evidence. The New York Times called the controversy “a national Rorschach test on the divisive subject of torture.” In 2009, two Harvard psychologists, Kurt Gray and Daniel Wegner, published the results of a more scientific test. The researchers seemed to cause a subject pain (by dipping her hand in ice water), then asked volunteers if she was answering a series of questions truthfully. In fact, the “subject” was acting, and the questions and answers were scripted.…

Derek Amato stood above the shallow end of the swimming pool and called for his buddy in the Jacuzzi to toss him the football. Then he launched himself through the air, head first, arms outstretched. He figured he could roll onto one shoulder as he snagged the ball, then slide across the water. It was a grave miscalculation. The tips of Amato's fingers brushed the pigskin—then his head slammed into the pool's concrete floor with such bone-jarring force that it felt like an explosion. He pushed to the surface, clapping his hands to his head, convinced that the water streaming down his cheeks was blood gushing from his ears. At the edge of the pool, Amato collapsed into the arms of his friends, Bill Peterson and Rick Sturm. It was…

When it opens in 2014, the Shanghai Tower won't just be the world's second-tallest building. The 2,073-foot-high skyscraper, designed by the San Francisco architecture firm Gensler, will be a showcase of 21st-century engineering, introducing the innovations that could become standard in the next generation of supertall towers. The building relies on three interlocking systems to remain upright. The first is a 90-by-90-foot concrete-and-steel core, which provides vertical strength. A ring of steel “super-columns” [above, left] surround the core, connected to it by steel outriggers. The columns buttress the building against lateral forces. Every 14 floors, two-story belt trusses hug the building's perimeter; each marks the start of a new zone. “The structure works like a wedding cake in nine sections,” says Dennis C.K. Poon, an engineer with the firm Thornton…

In 1921, two scientists made the first modern loudspeaker out of magnets, wire, and paper. Now manufacturers use synthetic fibers and even ferrofluid. Why stop there? Your kitchen contains plenty of materials to build a functional woofer. A potato chip works as a sound-emitting diaphragm here, but other rigid foods work just as well. Wrap the magnet wire tightly around the dowel to make a -inch-tall coil, leaving 12 inches of wire on each end. Smear the coil with hot glue, let it cool, and slide the coil off the dowel. Sand an inch of paint off the wire's ends. Fold the cardboard strips into a Z shape. Hot-glue the magnets and strips to the particleboard, and then the coil to a chip. Next, glue a cardboard strip to each…

Q:Which came first: the chicken or the egg? SHORT ANSWER The egg LONG ANSWER Chickens, as a species, became chickens through a long, slow process of evolution. At some point, a chicken-like bird produced an offspring that, due to some mutation in its DNA, crossed the threshold from mere chicken likeness into chicken actuality. That is to say, a proto-chicken gave birth to a real-life official chicken. And since that real-life official chicken came out of its own egg, we can say that the egg came first. Another way to look at the question would be to ask which came first in evolutionary history. Once again, the egg takes precedence. Many characteristics of the modern avian egg—namely an oblong, asymmetrical shape and a hardened shell—were in place before birds diverged…

Tom Foster investigated the football-helmet industry in January's “The Helmet Wars.” Online readers had their own ideas about the role of helmets in sports. Instead of a better helmet, amend the rules. In rugby, soft helmets are optional and not worn by many players. Head injuries are not a major problem. African Rover This article could apply to cycling helmets. In very oblique impacts, helmets can convert a minor injury into a brain injury. In areas that mandate helmet use for cyclists, an ethical issue arises. We should be reluctant to exchange the risk of a laceration or fractured skull for the risk of a brain injury. AveryB…

Diesel-engine designers have long grappled with a dilemma: Reducing emissions meant either cutting efficiency or adding expensive equipment. With the Skyactiv-D, Mazda engineers decreased pollution, boosted mileage, and eliminated the cost of exhaust after-treatments by building the world's lowest-compression diesel engine. They then added two turbochargers and a capacitor-based regenerative braking system. When it arrives in U.S. showrooms late this year, the Skyactiv-D—equipped Mazda6 should deliver approximately 56 highway mpg while meeting strict emission standards, proving that diesel engines have many miles left in them. A two-stage turbocharging system contains a small turbine that boosts low-end torque, as well as a larger turbocharger that increases high-end horsepower. An electronic controller runs the turbochargers, tuning performance to conditions. The Skyactiv-D's engine overhaul has a side benefit: Engineers were able to build…

TODAY'S industrial robots have superhuman power, precision, and speed to tirelessly paint, weld, and transport massive objects. But they have to be programmed for each specific task (and if one accidentally smacks you in the face, it could kill you). And so, for all their success in factories and warehouses, robots remain conspicuously absent from our homes and everyday lives. To make human- and robot-kind more compatible, researchers have begun to develop machines with soft, deformable parts instead of hard ones. The promise of these squishy bots is twofold: They could operate more safely around other squishy objects—like us, for example. More important, their malleability makes them versatile enough to interact with a variety of objects (credit cards, dog food, coffee cups) without becoming astronomically expensive. Barry Trimmer, of Tufts…

The ocean covers nearly three quarters of our planet, yet humans have probed a mere 5 percent of it. To better explore its greatest depths, scientists will soon board the revamped Alvin, the workhorse of human-operated deep-submergence vehicles. Owned by the U.S. Navy and operated by Woods Hole Oceanographic Institution on Cape Cod, the sub has logged 4,664 dives since 1964. It has explored the Titanic wreck 12 times, retrieved a lost live H-bomb, and survived a swordfish attack. Next month, engineers will begin sea trials to scrutinize its seven-year-long $40-million update (still cheaper than the $50-million-plus it would have cost to build a sub from scratch). New features include a larger cockpit with more windows, wider-reaching arms, and HD cameras. Alvin's team also started upgrading the vehicle to withstand…

A device delivers targeted drugs to calm overactive neurons For years, large clinical trials have treated people with epilepsy using so-called deep-brain stimulation: surgically implanted electrodes that can detect a seizure and stop it with an electrical jolt. The technology leads to a 69 percent reduction in seizures after five years, according to the latest results. Tracy Cui, a biomedical engineer at the University of Pittsburgh, hopes to improve upon that statistic. Her group has designed an electrode that would deliver both an electrical pulse and antiseizure medication. “We know where we want to apply the drug,” Cui says, “so you would not need a lot of it.” To build the device, Cui's team immersed a metal electrode in a solution containing two key ingredients: a molecule called a monomer…

The inspiration for Rain Man, Peek could read two pages of a book simultaneously (one with each eye) and instantly commit them to memory. His recall of more than 12,000 books made him a walking encyclopedia. Peek, who died in 2009, could also sum columns of numbers in the telephone book. Wiltshire, who is autistic, was drawing buildings by age 8. As an adult, he has created stunningly accurate portraits of cities from memory. In 2007, he flew over the Thames for 15 minutes, then sketched seven square miles of London's streets, rivers, and buildings, precise down to the windows. Blind since birth, Lemke has a verbal IQ of 58. When he was 14, his family watched a movie featuring a Tchaikovsky piano concerto. Hours later, his mother awoke to…

BRITTA RILEY grew up in rural southeast Texas, where locals with a mastery of gardening subsisted on their land. “They really turned me on to the idea of growing my own food,” Riley says. With the help of an open-source community, Riley now has her own productive plot—a 20-by-30-foot vertical garden hanging in a glass pavilion at New York City's American Museum of Natural History—and a start-up to put similar farms in windows around the world. After Riley moved to Brooklyn, New York, in 2003, she grew potted vegetables in her dimly lit apartment. The results were far from successful. Her plants strained for light on a confined windowsill, and they poured their energy into growing expansive root systems instead of lush, edible greens. A rooftop garden, meanwhile, exposed her…

Sam van Doorn couldn't let a friend trash a 1970s-era pinball machine, so the Dutch graphic artist turned it into a printer. Van Doorn stripped away the game's haggard facade and repaired its inner workings. Then he tested 50 types of paper as ready-to-ink playing surfaces. Van Doorn named the machine STYN after his friend Styn Geurts, who helped with the build. STYN's pinballs bang around like those in any arcade classic, but they're dipped in lithographic ink. Every roll marks the ball's movement—and each game's unique play pattern—onto the paper. TIME 6 months COST $1,316…

Q:Do meteor showers ever run out of meteors? SHORT ANSWER Yes, but it takes a long, long time. LONG ANSWER Meteor showers occur when the Earth passes through a field of cosmic debris. As that debris crosses into the Earth's atmosphere, each piece burns up, sometimes creating the blazing streaks of light we call shooting stars. These chunks of rock or ice are gone for good, so it's true that a meteor shower loses some of its material, or fuel, with every flurry. But there are ways for a shower to be replenished, says David Meisel, executive director of the American Meteor Society. The Geminids, which appear every December, are fragments from an asteroid called 3200 Phaethon. When 3200 Phaethon swings past the sun, it heats up and pieces break…