Tuesday, November 24, 2015

The Physics Of Non-Newtonian Goo Could Save Astronauts' Lives

The slimy, gloopy, colorful oobleck has a very interesting set of properties.

Flickr User Trevor Cox

There's an experiment you may have done in high school: When you mix cornstarch with water—a concoction colloquially called oobleck—and give it a stir, it acts like a liquid. But scrape it quickly or hit it hard, and it stiffens up into a solid. If you set the right pace, you can even run on top of a pool of the stuff. This phenomenon is called shear force thickening, and scientists have been trying to understand how it happens for decades.

Watch the difference in thickness between plain water and when it's mixed with cornstarch here:

Credit: Cohen Lab

There are two main theories, and figuring out which is right could affect the way we make things like cement, body armor, concussion preventing helmets, and even spacesuits.

The prevailing theory is that it's all about the fluid dynamics (the nature of how fluids move) of the liquid and the particles in a solution. As the particles are pushed closer and closer together, it becomes harder to squeeze the liquid out from between them. Eventually, it's too hard to squeeze out any more fluid and the particles lock up into hydrodynamic clusters, still separated by a thin film of fluid. They then move together, thickening the mixture and forming a solid.

The other idea is that contact forces like friction keep the particles locked together. Under this theory, when force is applied, the particles actually touch. The shearing force and friction keep them pressed together, which makes the solution more solid.

There are two main theories, and figuring out which is right could affect the way we make things like cement, body armor, concussion preventing helmets, and even spacesuits.

"The debate has been raging, and we've been wracking our brains to think of a method to conclusively go one way or the other," says Itai Cohen, a physicist at Cornell University. He and his team recently ran a new experiment that seems to point to friction as the driving cause of shear thickening.

They decided to perform what is called a flow reversal experiment. They put a cone into a dish full of the fluid and measured the torque it takes to spin the cone. As shear thickening begins, it gets harder to spin the cone. Then they suddenly reverse the spin direction. The idea is that if contact force is the cause of shear thickening, then the moment the spinning reverses, the particles will pop free of each other, and there will be an immediate drop in the magnitude of torque. If hydrodynamic clusters were the main cause of shear thickening, the torque wouldn't drop.

The problem is that the force has to be measured immediately, and there wasn't a machine that could make that measurement fast enough to see the effect. So Cohen's team partnered with Gareth McKinley at MIT, who altered the machine to get the data more quickly. When they tested simple solutions they had made, they saw that characteristic drop in force after they reversed the flow. Further modeling suggested that friction might be the contact force at play.

"We are giddy with excitement," Cohen says. His results were published today in the journal, Physical Review Letters.

People could design mixtures that either stiffen up or stay fluid, depending on what they want to do with them.

"It's an excellent piece of work," says Jeffrey Morris, a chemical engineer who studies fluid mechanics at the City College of New York. But he does point out that Cohen's results might not be generalizable to every shear thickening fluid. "I think they've shown that friction is the right explanation for their system, but other systems may need to be tested on a case by case basis," he says.

Norman Wagner, a chemical engineer at the University of Delaware, says that research into frictional interactions like this is important, but notes that he isn't completely convinced as Cohen's team didn't measure friction directly (they inferred it was friction from their modeling however they didn't find the exact measurement of the friction between the particles). He also says that there's a lot of data in the field already that strongly indicates hydrodynamic clusters as the cause for shear thickening.

However, the researchers all agree that once the exact cause of shear thickening is nailed down, the applications that could follow are vast. "Once you know the mechanism that's causing the phenomenon, you can tailor particle properties to change it," says Morris. People could design mixtures that either stiffen up or stay fluid, depending on what they want to do with them, he says.

For example, you want to be able to easily spray or roll paint on your wall without it clumping up. Researchers had to design paint so that it did not shear thicken. The same goes for cement, which needs to be poured at high speeds without seizing. On the other hand, shear thickening fluids can make body armor that hardens on impact, spreading the force across a larger part of the body, says Wagner. That protects soldiers, police, and EMTs from things like stab wounds or fragments flying through the air during an explosion.

Watch this cornstarch and water mixture harden against a hammer strike, then return to a fluid:

Credit: Cohen Lab

"And if we can protect soldiers," he says, "why not astronauts?" Wagner and his team are working on a NASA funded project to improve space suits so that micrometeorites or other debris can't puncture them. They have also bent their technology to make padding for helmets and shin guards that would do a better job protecting athletes from harmful impacts. They are even making puncture resistant gloves that would give healthcare workers the same dexterity as current ones but with extra protection against accidental needle sticks.

"It's a very exciting area," says Wagner. He's very interested in designing materials that automatically protect someone, without robotics or power. It's just the innate physics of the material, he says. "We can harness nature to work to our advantage to make it respond in a way that protects us."

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Who are the Turkmen rebels who claim to have killed 2 Russian pilots?


Turkmen rebels in Syria have claimed responsibility for shooting dead two Russian pilots who ejected from a military plane as it plunged towards the ground near the Syrian border with Turkey on Tuesday

Turkey shot down the Russian Sukhoi Su-24 military plane near its border with Latakia, Syria, according to Turkish officials. Russian officials have said the plane had stayed above Syria while their Turkish counterparts said it had encroached upon their airspace.

Turkish Prime Minister Ahmet Davutoglu defended the downing of the fighter jet at the border with Syria, saying the country has the right "to take all kinds of measures" against border violations. He stood by charges that the plane violated Turkish airspace and ignored several warnings to leave the area. Russia, meanwhile, has denounced the attack, calling it a "stab in the back by the accomplices of terrorists" and said it would have "serious consequences for Russian-Turkish relations." Read more...

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Airbus A320neo Receives Joint EASA and FAA Type Certification

By: Roberto Leiro / Published: November 24, 2015

The Airbus A320neo has received today the joint Type Certification from the European Aviation Safety Agency (EASA) and the Federal Aviation Administration (FAA), clearing the path for the initial deliveries of the aircraft to its customers.

Both type certifications were granted to the A320neo powered by Pure Power PW1100G-JM engines produced by Pratt & Whitney, engine division of United Technologies Corp. The A320neo with CFM engines will be certified in the coming months, the A321neo and A319neo in both engines variants will follow suit.

RELATED: First Airbus A320neo Rolls Out of Factory

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A320neo_first_flight_air_to_air_3According to the manufacturer, the three flight test aircraft powered by Pratt & Whitney engines accumulated over 1,070 flight hours in some 350 flights. Interestingly, 300 flight hours were completed with the same aircraft in an airline-like environment, intended to assure operational maturity at entry into service.

"This double seal of approval represents a great achievement for Airbus. It recognizes the hard work performed by all the teams at Airbus and Pratt & Whitney. It demonstrates the A320neo is meeting all requirements," said Fabrice Brégier, Airbus President and CEO. "The A320neo is now cleared for its first delivery and ready to offer many airlines its winning combination of unbeatable economics and outstanding cabin comfort."

The 'neo' or 'new engine option' is an upgrade of Airbus popular single aisle family which also includes other enhancements intended to improve fuel efficiency and range of the plane. According to Airbus, the A320neo should be 15% more efficient than the current engine option or 'ceo'.

Airbus builds the A320 in production plants in France, Germany and China, and last September inaugurated a new Final Assembly Line in Mobile, Alabama, to serve the North American market. The airframer is readying a major production ramp up of its A320 family aircraft, intended to satisfy the growing single-aisle demand in emerging markets such as Southeast Asia and China. The Airbus order book  at the end of October showed a backlog of 5,466 A320 family aircraft in both ceo and neo types.

Airbus has promised to deliver the first of the A320neos this year. Qatar Airways is the lead operator of the new plane.

RELATED: Airbus to Ramp Up A320 production to 60 a Month Before 2020

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PARIS AIR SHOW SPECIAL: Airlines Go Shopping in the Airbus Catalog

RELATED: Airbus Inaugurates First U.S. Final Assembly Line in Mobile, Alabama

5k7s85PpRoberto Leiro is the Executive Editor at AirwaysNews.com. An aviation passionate since early childhood, Roberto started with other fellow enthusiasts Venezuela's first aviation photography / news organization svzm.aero. Follow him on twitter @rleiro and reach him via e-mail at roberto.leiro@airwaysnews.com.

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Monday, November 23, 2015

Behold the Dizzying Pedestrian Bridge Copenhagen Is Building Above Its Harbor

Cities can learn a lot from Copenhagen's multimodal ways. But how about this inspiring piece of infrastructure from the Danish city: Instead of simply adding a frilly statue to mark its harbor's entrance, this bridge incorporates housing and provides a stunning vista for tourists and residents alike.


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NASA paying $1.16 billion so Aerojet Rocketdyne can start making engines for Mars

NASA wants a whole new crop of rocket engines from engine manufacturer Aerojet Rocketdyne. The space agency just awarded the company a $1.16 billion contract, restarting Aerojet's production line for its RS-25 engines. Four RS-25s will be used as the primary engines in NASA's next big rocket, the Space Launch System (SLS), which could take humans into deep space and on to Mars someday.

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KLM has Big Dreams for the Dreamliner

By: Seth Miller / Published: November 23, 2015

KLM is the latest member of the Boeing 787 club, having taken delivery of is first Dreamliner on 13 November 2015. The carrier wasted little time pressing the aircraft into service, with the inaugural commercial service (Abu Dhabi is the first destination) coming just a day after a series of test flights took aficionados out for hour-long joy rides over the Dutch coastline. And, while the entry into service was delayed a bit from initial projections, KLM is very excited about the potential the new type brings.

Speaking on board the aircraft during one of tour flights KLM's Chief Operating Officer René de Groot expressed optimism about the 787 and what it means for the carrier overall.

For us, it means a new phase of the company. Investing in new technology. Investing in new products for our customers. We had some tough times over the last couple of years. We're now getting into the new phase and we're not only looking back at the history but building on a future again.

The 787 has played a similar role at many other airlines. Whether fueling the massive international expansion of LCC Norwegian Air Shuttle or allowing more new routes to be added, growth is one of the key plays the 787 enables. For KLM, however, that is secondary. The initial plan is to replace the aging 747-400 fleet, with expansion coming further down the line. Which is not to say that the company is shying away from such discussions; de Groot mentioned the success of the recently added Edmonton service as an example of a market which will benefit from having the 787 in the fleet. KLM has 15 of the –9 variant on order and another 6 of the –10 set to join the fleet.

RELATED: Realizing the 787 Dream: New Routes Come to Life on the Dreamliner

From a passenger perspective the 787 offers an all-new business class product, featuring private, fully-flat beds with direct aisle access for each of the 32 customers in the cabin. In economy class the layout is 3-3-3, matching nearly all other 787 configurations. KLM does offer an Economy Comfort section with increased pitch and larger in-seat IFE screens than its other aircraft. The 787s are also the first of KLM's subfleets to be equipped with in-flight internet service; the carrier is using Panasonic Avionics' Ku-band kit, installed at the Boeing factory, for connectivity. These improvements should result in a more comfortable passenger experience for all on board.

KLM Boeing 787-9 Business Class KLM Boeing 787-9 Economy Class


As for the celebratory flights to launch service, KLM clearly understands the AvGeek nature of its customers. Passengers gift bags included copies of the in-flight safety cards, for example, knowing that many would otherwise have disappeared off the plane anyways. Speaking with others on board the reasons for participating varied as much as the demographics of the travelers. Young and old alike expressed excitement for KLM's acquisition of the new plane and getting to try out the experience on the special flights.

787 Dreamliner 001

The hour-long flight was nothing short of a party in the sky. Very few passengers seemed to be in their seats for the duration. Many were up in the aisles, meeting the others on board and trading stories. It was also an opportunity for those seated in the economy cabin to explore World Business Class and vice versa, though more were moving forward on the plane than to the back. The carrier even hosted a trivia contest on board, awarding the winner a model of the 787-9. The flight stayed low – around 2500 feet – for the duration which meant no opportunity to test out the in-flight internet service, though it did offer up some spectacular views of Holland as we flew about.

KLM 787 Seth

And then, all too soon, the plane returned to Schiphol and the party was over. KLM was smart in blocking extra time for the boarding and disembarkation portions of the event; it took much longer than a typical flight but with good reason. Unlike most trips this one it was all about the flight, not the start or end.

n.b. Airways News was a guest of KLM for this trip.

IMGP2946Seth Miller is an AirwaysNews.com contributor specialized in Loyalty Marketing, Connectivity and Passenger Experience and will drop everything if he gets an opportunity to go flying. Bit by the travel bug 30 years ago, Seth flies ~200,000 miles annually. Follow him on twitter at @WandrMe, or his site at The Wandering Aramean blog.

Editor's note: Keep up with AirwaysNews by subscribing to our weekly eNewsletter. Every Saturday morning, subscribers get a recap of our top stories of the week, the subscriber-only exclusive Weekend Reads column wrapping up interesting industry stories and a Photo of the Week from the amazing AirwaysNews archives. Click here to subscribe today!

Contact the editor at roberto.leiro@airwaysnews.com

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Sunday, November 22, 2015

Vettel wins Race of Champions, England takes Nations Cup [w/videos]

Filed under: Motorsports

This year's Race of Champions saw Sebastian Vettel defeat Tom Kristensen, and a pair of English touring car champs take down the Germans for the Nations Cup in heated competition in London's Olympic Stadium.

Continue reading Vettel wins Race of Champions, England takes Nations Cup [w/videos]

Vettel wins Race of Champions, England takes Nations Cup [w/videos] originally appeared on Autoblog on Sun, 22 Nov 2015 13:01:00 EST. Please see our terms for use of feeds.

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Kyle Busch completes ultimate NASCAR comeback with Sprint Cup championship


HOMESTEAD, Fla. (AP) — Kyle Busch opened the season in a hospital bed and ended it in victory lane with the championship trophy.

Busch completed the ultimate comeback Sunday night by winning his first career Sprint Cup title just nine months after a serious crash at Daytona nearly ended his season. He crashed into a concrete wall the day before the Daytona 500 and broke his right leg and left foot.

SEE ALSO: Why Kyle Busch is the NASCAR driver you can't root against right now

Despite multiple surgeries and grueling rehabilitation, Busch missed only 11 races and was back in his Joe Gibbs Racing Toyota in late May. NASCAR granted him a waiver to race for the championship if he earned a berth in the playoffs, and Busch was off and running. Read more...

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The US and China now have a 'space hotline' to avoid satellite warfare

Washington and Beijing are making efforts to avoid a crisis in space before it happens. The US and China have set up a direct link — or "hotline" — allowing both nations to easily share information about activities in space. Specifically, the so-called space hotline is designed to help the space and military agencies of both countries to discuss "potential collisions, approaches, or tests," according to The Financial Times.

Like the well-known "red telephone," set up between Moscow and Washington in the aftermath of the Cuban Missile Crisis, the idea is to keep a misunderstanding or other miscommunication from escalating to a dangerous situation in space and here on Earth.

According to a US assistant secretary of state, before the...

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Saturday, November 21, 2015

100 Years of General Relativity: Why Einstein Still Stands

Albert Einstein

Albert Einstein as seen in a photograph from the U.S. Library of Congress

Albert Einstein is pictured in this photo from the Library of Congress dated 1900, about 15 years before the scientist began publishing a series of papers describing his theory of General Relativity, which remains a bedrock of modern physics 100 years later.

One hundred years ago this month, Albert Einstein redefined what gravity is, overthrowing his own hero Isaac Newton.

Newton had imagined gravity to be a force like any other that pulls on things to get them going. But Einstein wove gravity into very fabric of space and time, molding an invisible landscape of hills and valleys through which objects move. The equations describing this vision, known as the general theory of relativity, have since become a cornerstone of modern physics—opening new doors for understanding everything from how planets and stars move to existence of dark matter and the early days of the universe itself.

"Today it really is the standard model for gravity," says Clifford Will, a physicist at the University of Florida who has devoted his career to the theory. "It has passed every experimental test with flying colors."

"It has passed every experimental test with flying colors."

That hasn't stopped people hoping to challenge the wild-hair genius from drawing up alternative theories. New ideas for modifying general relativity have multiplied in recent years. Some add extra dimensions to the universe. Others invent brand-new particles. All have one thing in common: no evidence has ever been found to back them up.

"There are hundreds of these theories in the scientific literature," said Tessa Baker, a theoretical physicist at the University of Oxford. "You can build all sorts of gravity theories that behave in all sorts of different ways."

No one seriously expects to ever throw out Einstein's equations entirely—except maybe the crackpots who sent unsolicited manuscripts in the mail to science journalists like me. But physicists have good reason to be grumpy about general relativity, despite its success. It doesn't get along with quantum mechanics, which governs the smallest scales of reality. And it includes a fudge factor that troubled Einstein himself, who added it to account for the accelerating expansion of the universe. But here in our own solar system, general relativity has proven itself time and time again.

Consider the planet Mercury. The elliptical path it traces through the heavens moves around over time. Newton's math could explain this precession for other planets, but not Mercury. It took Einstein to identify the cause: warped spacetime near the Sun has a pronounced effect on Mercury, the closest planet to the Sun.

General relativity also predicted how much those distortions from the Sun's gravity should bend a ray of light passing nearby. Teams of British astronomers who traveled to South America and Africa famously confirmed that prediction by photographing stars visible close to the Sun during a solar eclipse.

Eddington 1919 Eclipse Negative verifying Einstein's general relativity

Negative of a solar eclipse verifying Einstein's general relativity

In this 1919 negative of a solar eclipse, British scientist Sir Arthur Eddington helped verify Einstein's theory of general relativity, showing light bending around the Sun as predicted in the theory.

Others have since cast doubt on that experiment—claiming that the astronomers perhaps saw what they wanted to see—but the ability of stars and other celestial entities to not only bend light but shift its color is now well-proven. Some heavenly bodies even focus the light coming from distant objects, acting as lenses that, for instance, help planet hunters to find alien worlds around faraway stars.

"About 5 to 10 years ago, people started to realize that we needed to test general relativity at larger scales."

Though Earth has a much weaker gravity than the Sun, technological advances have made it possible to confirm its uncanny effects closer to home. Spinning gyroscopes in orbit aboard NASA's longest-running mission, Gravity Probe B, moved wobbled in a way consistent with Earth's mass both warping the fabric of spacetime like a bowling ball on a trampoline and twisting it like a spoon twirled in honey. Here on the surface, the world's most precise clocks, which keep time with vibrating atoms, tick slightly slower if placed on the floor instead of the table—thanks to the slightly stronger gravity on the floor slowing down time.

Relativity illustration showing NASA's Gravity Probe B

Illustration of spacetime warping around Earth

In this NASA illustration, the effects of Earth's gravity can be seen warping spacetime in accordance with Einstein's theory of general relativity. NASA's Gravity Probe B spacecraft is also depicted.

Thwarted by planets and stars, those hoping to poke holes in Einstein's theory have begun to look to uncharted water elsewhere in the universe.

"About 5 to 10 years ago, people started to realize that we needed to test general relativity at larger scales," says Luca Amendola, a theoretical physicist at the University of Heidelberg.

New projects that will check relativity's predictions for the structure of the universe itself include European space mission Euclid and the Large Synoptic Survey Telescope, which broke ground this year in Chile and will use a panoramic camera to photograph galaxies.

Large Synoptic Survey Telescope illustration

Artist's rendering of the Large Synoptic Survey Telescope (LSST)

Artist's illustration showing the Large Synoptic Survey Telescope currently under construction at Cerro Pachón, Chile. The reflecting telescope includes the world'es largest digital camera and will survey the entire night sky every three nights for 10 years in an effort to understand its structure.

Others are focusing on the most gravitationally awesome objects in the universe: black holes.

"We want to test gravity in different regimes," says Dimitrios Psaltis, an astrophysicist at the University of Arizona. "We want to see if we can find evidence of new physics that appears beyond some threshold."

Psaltis has joined an international team of astronomers watching the black hole that lives at center of our galaxy. The black hole itself is invisible; its gravity is so strong that nothing crossing its event horizon, including light, can escape. But just outside of the event horizon lies a hazy ring of light and radio waves given off by dust falling into the black hole.

Nearly a dozen telescopes on four continents are tuning in to those radio waves to check whether that ring has the size and shape predicted by general relativity. Synchronized with atomic clocks, the network functions as one giant virtual telescope: The Event Horizon Telescope, which stretches from Spain all the way down to the newest member of the collaboration that joined this spring, the South Pole Telescope.

A European space mission due to launch this month also has black holes on the brain. Called LISA Pathfinder, it will try out technologies destined to fly on a 2034 mission, eLISA, that will check out what happens when two black holes orbit each other.

LISA Pathfinder illustration

ESA LISA Pathfinder illustration

Artist's rendering of the LISA Pathfinder spacecraft, which will test the concept of low-frequency gravity waves.


General relativity predicts that such couples should create waves in spacetime that ripple outward, causing objects to expand and contract. LIGO, a ground-based instrument recently upgraded in September, has been trying unsuccessfully to catch those gravitational waves for years. eLISA will cast its net using three sets of free-floating objects.

In the quiet of space, the distance between those objects, as measuring by lasers that link the three spacecraft carrying them, should change slightly if a wave from two black holes in two merging galaxies passes by.

Catching a wave would not necessarily confirm Einstein's theory

"LISA should see a few tens of these merger events over the length of the mission," said Jonathan Gair at the University of Cambridge.

Catching a wave would not necessarily confirm Einstein's theory; it must change distances only in directions perpendicular to the wave itself. Otherwise, physicists will need to go back to the drawing board.

Theorists can tell us little today about what new physics would be needed if any of these projects finds something strange. They will continue to play with their toy theories—refining and revising the math and throwing out ones that have problems—in the absence of an evidence to justify them. But they will dream of the day that the data challenges Einstein. Until then, his theory of gravity will continue its now-century-long reign.

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