20 Most Dangerous Bridges in the World


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20 Most Dangerous Bridges in the World

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6. The Bridge of Immortals, Huang Shang China.
There are many interesting bridges in the world. Some are dangerous, while others only appear to be so.
Here are 20 of the most dangerous (and dangerous-looking) bridges in the world.

The Royal Gorge Bridge

20. Royal Gorge Bridge, Colorado.

royalgorgebridge.com
The Royal Gorge Bridge in Colorado is the highest suspension bridge in the United States. That’s not the impressive part though.
What makes this bridge so interesting is that it didn’t have any wind cables when it was built in 1929. Those were added decades later, and today, the bridge is quite a tourist attraction.

The Monkey Bridges

19. Monkey bridges, Vietnam.

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The Monkey Bridges in Vietnam are a series of bridges that offer access across the Mekong Delta.
What makes these bridges so popular is that they are made from single pieces of bamboo. And how do you cross these types of bridge? Look at a monkey and do what they do.

The Hussaini Hanging Bridge

18. Hussaini Hanging Bridge, Pakistan.

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Located in Pakistan, the Hussaini Hanging Bridge is easily among the most dangerous bridges in the world.
The swinging bridge stretches across the Hunza river and is covered with all sorts of cracks. And to make matters worse, the tattered remnants of the old bridge hangs nearby.

The Seven Mile Bridge

17. Seven Mile Bridge, Florida.

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The Seven Mile Bridge located in Florida is actually the second iteration of the original Seven Mile Bridge decommissioned years ago because it prevented boats to pass through.
Although it may appear safe, this particular bridge can be quite scary during one of Florida’s Hurricane seasons.

The Deception Pass Bridge

Deception Pass Bridge is a Washington State bridge that connects two local islands. Prior to the construction of the bridge, these islands were only accessible via ferry. Although the bridge itself looks safe, it is 180 feet high and quite intimidating.

The Pontchartrain Causeway

The Pontchartrain Causeway located in Pontchartrain, Louisiana is the longest bridge to cross over water in the world, even if it only stands 16 feet high.

What makes this bridge so scary, however, is that it’s actually possible to lose sight of land somewhere along the way, which makes some people feel as though they are traveling across a never-ending bridge.

The Canopy Walk

The Canopy Walk, which is located in Ghana, is suspended 40 feet in the air and is around 1000 feet in length.

What makes this particular bridge interesting is that it involves walking through several trees, where visitors will encounter monkeys or even birds along the way.

The Langkawi Sky Bridge

The Langkawi Sky Bridge in Malaysia hovers over 400 feet from the ground. What makes this bridge so scary is that it was once closed due to rumors that it had the potential to collapse.

Although the bridge has been ascertained to be structurally safe, its bad reputation has not gone away.

The Mount Titlis Bridge

The bridge over Mount Titlis in Switzerland stretches above the Swiss Alps. It is approximately 3000 meters from the ground and is quite narrow.

Despite the extreme height, though, the bridge is considered as one of the safest in the world.

The Vitim River Bridge

This particular bridge is located in Russia. Aside from its wooden components and old age, the bridge also lacks any guard rails.

To make matters worse, it also lacks a few wooden planks, and is quite dangerous during winter.

Puente de Ojuela

This Mexican bridge was originally established to serve the mining town beneath it. Today, only pedestrians are allowed to use the bridge, as vehicles may not be able to make it all the way across. It is also considered one of the most dangerous bridges in the world.

Quepos Bridge

The Quepos Bridge in Costa Rica is an old wooden plank bridge with many gaps. How do we know that this is a dangerous bridge? It has the nickname, “Bridge of Death.”

Sunshine Skyway Bridge

This relatively recent bridge in Florida was constructed in the 1980’s to replace an existing bridge that had been destroyed by a tanker collision.

Although the bridge itself is quite safe and secure, it has developed an infamous reputation over the years. It has become associated with numerous suicides, and there are rumors that it is haunted.

Eshima Ohashi Bridge

The Eshima Ohashi Bridge in Japan has a reputation for being terrifyingly steep. However, looks can be deceiving.

Despite its appearance, it has a gradient of only 6.1% and is only about 144 feet tall, so it’s not quite as unstable as it seems.

The Bridge of Immortals

This bridge with the strange name is located in China. This bridge allows people passing by to look down from above the clouds, which helps to explain its name.

The only problem is that getting to the bridge takes time, and the process can be quite scary

The Montenegro Rainforest Bridge

This particular bridge in Costa Rica was constructed amidst one of the most diverse rainforests in the world. It offers a great view of the surrounding areas and more.

The only trouble, thought, is that the bridge may have a few missing planks and other potential hazards.

The U Bein Bridge

The U Bein Bridge in Myanmar looks as though it’s still under construction, but it’s actually complete.

It spans around 1 km in length and has a very hazardous look. But despite its unusual appearance, it’s actually quite safe to use.

The Storseisundet Bridge

The Storseisundet Bridge in Norway was designed to feature angles that appear as though they will drop off.

Unfortunately, describing the dread that this bridge inspires is rather difficult, but according to people who have gone there, the bridge makes you feel like you’re on a roller-coaster just before it

The Carrick-a-Rede Rope Bridge

The Carrick-a-Rede Rope Bridge in Ireland is suspended 30 meter above rocky waters. What makes this bridge interesting is that most people only use the bridge to reach the island on the other side.

When it’s time for them to come back, they use the local ferry. Even more interesting is the fact that the bridge charges a fee.

The Sidu River Bridge

The Sidu River Bridge in China has the title of highest bridge in the world, and connects Shanghai with Chongqing.

Not only is this bridge sturdy, it also offers a great view. However, it’s not the kind of place you might visit if you’re afraid of heights.

 

 

 

This Supercomputer Can Calculate in 1 Second What Would Take You 6 Billion Years


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This Supercomputer Can Calculate in 1 Second What Would Take You 6 Billion Years

This Supercomputer Can Calculate in 1 Second What Would Take You 6 Billion Years

To keep Summit from overheating, more than 4,000 gallons of water pump through its cooling system every minute, according to Oak Ridge National Laboratory where the beast is housed.

Credit: ORNL

 

It’s shiny, fast and ultrapowerful. But it’s not the latest Alfa Romeo. A physics laboratory in Tennessee just unveiled Summit, likely to be named the world’s speediest and smartest supercomputer.

Perhaps most exciting for the U.S.? It’s faster than China’s.

The supercomputer — which fills a server room the size of two tennis courts — can spit out answers to 200 quadrillion (or 200 with 15 zeros) calculations per second, or 200 petaflops, according to Oak Ridge National Laboratory, where the supercomputer resides.

“If every person on Earth completed one calculation per second, it would take the world population 305 days to do what Summit can do in 1 second,” according to an ORNL statement.

Put another way, if one person were to run the calculations, hypothetically, it would take 2.3 trillion days, or 6.35 billion years. [9 Super-Cool Uses for Supercomputers]

The former “world’s fastest supercomputer,” called Sunway TaihuLight, can perform 93 quadrillion calculations a second (93 petaflops), while humming away inside China’s National Supercomputing Center in Wuxi.

So, how did Summit become such a giant?

The supercomputer is an IBM AC922 system that’s made up of 4,608 computer servers — each comprising processors (the brains of the computer). But what’s actually going on inside these processors is what makes the difference.

“Summit’s computer architecture is quite different from what we have had before,” Daniel Jacobson, a computational biologist at ORNL, who is working on Summit, told Live Science. For one thing, the computer uses the new Tensor Core feature in its graphics cards (made by Nvidia), which is designed specifically for applications focusing on machine learning and artificial intelligence (AI), and to be fast.

Basically, unlike older computer chips, these chips are optimized for a special type of mathematical operation on matrices — or rectangles filled with numbers with rules for adding, subtracting and multiplying the different rows and columns. Computers equipped with AI programs often learn using so-called neural networks, which have several layers in which lower calculations feed into higher ones. And this process requires the heavy use of matrices.

“This is a brand-new feature that has allowed us to break the exascale barrier,” Jacobson said, referring to a processing speed that’s over a billion billion calculations per second.

In addition, Summit has loads of superfast memory (RAM) available on each of its nodes, where localized calculations can take place.

“Each node on Summit has 512 Gb [gigabytes] of RAM and the network that communicates between nodes uses adaptive routing, and is thus incredibly fast, which helps us scale the calculation across all the nodes very efficiently,” Jacobson said. So-called adaptive routing means Summit has some flexibility in how it runs calculations — sort of like networks of brain cells connected to synapses.

And though pricey — a New York Times report puts the cost at $200 million — Summit could deliver big for science: The supercomputer is built to integrate artificial intelligence into its computing, which could make Summit a formidable foe in the battle for answers to some of the world’s most complex mysteries.

“There are many, many scientific uses of this sort of supercomputing capacity,” he said. “Whether this is for new discoveries for bioenergy or new discoveries for precision medicine, many things are now possible that simply weren’t before.”

For instance, just as artificial intelligence programs are being co-opted to learn to pick out cats from images, said Jack Wells, the director of science at ORNL, these AI programs running on Summit could learn to pick out and categorize all kinds of data, ranging from those in biological sciences to physics, such as detections of neutrinos and other particles.

“Something new that’s happening, is it’s going to be at the intersection of machine learning and simulation science, because this machine is going to be able to do both of those things in a very significant way,” Wells told Live Science.

Summit’s placement as the “world’s fastest” isn’t exactly official yet, because the Top500 list for supercomputer rankings hasn’t been updated yet, but according to the Times article, it should get the top slot when the list is updated later this month.

Editor’s Note: This article was updated to correct the speed of the former “world’s fastest supercomputer.”

Originally published on Live Science.

Russia Wants to Blast Space Junk with Laser Cannon


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Russia Wants to Blast Space Junk with Laser Cannon

Russia Wants to Blast Space Junk with Laser Cannon

Ground-based lasers developed by the USSR decades ago — conceptually illustrated here by artist Edward L. Cooper — were capable of interfering with some U.S. satellites.

Credit: U.S. Department of Defense

Russian. Space. Lasers. That’s right, Russian scientists are developing cosmic guns capable of blasting some of the half-million bits of space junk orbiting our planet into oblivion.

Precision Instrument Systems — a research and development arm within the Russian space agency, Roscosmos — recently submitted a proposal to the Russian Academy of Sciences (RAS) for transforming a 3-meter (10 feet) optical telescope into a laser cannon, the RT network reported.

Scientists at Russia’s Altay Optical-Laser Center will build this debris-monitoring telescope. Then, to turn it into a debris-vaporizing blaster, the researchers plan to add an optical detection system with an onboard “solid-state laser,” according to the Sputnik news agency. [How Do Laser Weapons Work? (Infographic)]

After that, it’s sizzle time. The cannon will train laser beams on pieces of orbiting detritus in low Earth orbit, heating up the bits of floating junk until they are entirely demolished, according to RT.

Human-made space junk consists of discarded or broken parts of spacecraft, launch vehicles and other objects sent into space, and it comes in many sizes. Approximately half a million bits whizzing around the planet are the size of a marble or bigger, and about 20,000 of those are at least the size of a softball, NASA reported in 2013. These bits travel at speeds of up to 17,500 mph (28,164 km/h), and at such speeds, even a relatively small particle of debris could seriously damage a spacecraft or satellite.

Low Earth orbit, the region of space within 1,242 miles (2,000 kilometers) of the planet's surface, is the most concentrated area for orbital debris.

Low Earth orbit, the region of space within 1,242 miles (2,000 kilometers) of the planet’s surface, is the most concentrated area for orbital debris.

Credit: NASA

 

In 2015, Japanese researchers presented plans for a spacefaring, debris-blasting laser mounted on a powerful telescope intended to detect cosmic rays, Space.com previously reported. Their study described combining many small lasers to produce a single powerful beam that would vaporize matter on the surface of space junk, generating a plume that would propel the debris lower in its orbital path, eventually causing the object to burn up in Earth’s atmosphere.

And earlier this year, researchers in China published a report proposing another laser-based approach to dealing with space garbage; their solution also suggested using satellite-mounted lasers to nudge orbiting debris into a lower orbit.

Clearly, space debris is a problem that would likely benefit from a futuristic solution like a laser cannon. However, while Precision Instrument Systems representatives confirmed the existence of their report to Sputnik, they “declined to elaborate further” on any details related to the project’s production time frame or its technical requirements.

Original article on Live Science.

1st Color X-Rays of Human Body Are Bloody Amazing


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1st Color X-Rays of Human Body Are Bloody Amazing

Stunning new color X-ray images, from a company called Mars Bioimaging, in New Zealand, seem to make flesh and bone translucent and hyperreal.

A scan of an ankle rotates in this GIF.

A scan of an ankle rotates in this GIF.

Credit: Mars Bioimaging

The gif above shows one of the company’s strange and fascinating images: a slice of human ankle, with off-white, rugged bones, bloody-looking muscle tissue and a pad of fat smeared protectively under the heel with a whipped-cream texture.

This image shows a wrist with more muscle, less visible bone, almost no fat and a clearly-articulated watch:

It’s important to note that these aren’t “true-color” X-ray scans as most people would commonly understand the term. As the inventors of the sensor that was used to make these images described in a 2015 paper in the journal IEEE Transactions on Medical Imaging and on the company’s website, the colors in these images are applied based on the computer’s detection of different wavelengths of X-rays passing through different substances. There are, however, no “true” red X-rays or “true” white X-rays; the device’s programmers assign different colors to different detected body parts. (What human brains interpret as color comes from different wavelengths of light in the visual spectrum bouncing off objects. Visible light is also a form of electromagnetic radiation but is lower-energy than X-ray light.)

To successfully distinguish muscle, fat and bone, Mars Bioimaging developed sensors that could fit inside computed tomography (CT) scanners (circular X-ray devices that produce three-dimensional X-ray images) and produce very detailed information about the wavelengths of individual X-ray photons that pass through and bounce off human tissue. By sensing the wavelengths that disappear after passing through a particular bit of tissue, the device makes a judgement about what chemicals make up that tissue and uses that information to figure out what sort of tissue it was. The photon-counting technology, the company says in its marketing materials, was originally developed as part of its founders’ work with CERN, the European Organization for Nuclear Research, which operates the world’s largest atom smasher.

By matching those scans with details about how different chemical compounds interact with X-ray light, they were able to distinguish different compounds in X-ray scans, the researchers wrote in the 2015 study. To produce these new grody, gorgeous color images of living tissue, they simply tasked the computer with painting the different compounds of fat, bone and muscle different colors.

The benefit for researchers, the company claims in its marketing materials, isn’t so much the fascinating visuals (though that’s a plus) as it is the wealth of precise chemical data on objects in the scanner. The careful, multilayered tissue scans, they write, will enable new precision in medical research.

Originally published on Live Science.

Russia’s Floating Nuclear Power Plant Heads for the Bering Strait


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Russia’s Floating Nuclear Power Plant Heads for the Bering Strait

World’s first floating nuclear power plant ‘Akademik Lomonosov’ passed Langeland, Denmark on May 4.

Credit: Tim Kildeborg Jensen/EPA-EFE/Rex/Shutterstock

Russia’s got a floating nuclear plant on a barge, and it’s heading for the Bering Strait — just a short hop from Alaska.

The “Akademik Lomonosov,” according to a statement from Russian nuclear energy company Rosatom, docked in the Russian port of Murmansk on Saturday (May 19). There it will receive its supply of nuclear fuel. Tugboats will eventually haul the nuclear plant to the town of Pevek in the Russian Far East — just 53 miles (86 kilometers), as Reuters noted, from the western edge of Alaska, across the Bering Strait.

The St. Petersburg-built power plant will replace a coal plant and an older, landlocked nuclear plant. It will serve a population of about 50,000 people, Rosatom said. [Top 10 Greatest Explosions Ever]

Rosatom pitches the Lomonosov as the first in a series of floating plants that will serve remote Russian communities and cut greenhouse gas emissions. There are objections from within the anti-nuclear wing of the environmental movement, which is represented by a subset of hardline environmental groups like Greenpeace and doesn’t necessarily include all environmentalists.

In an April 26 blog titled “What Could Possibly Go Wrong with a Floating Nuclear Power Plant?” Greenpeace nuclear experts Jan Haverkamp and Rashid Alimov suggested these plants will primarily serve to power Russian fossil-fuel extraction efforts in the de-iced Arctic, and said, “If this development is not halted, the next nuclear catastrophe could well be aChernobyl-on-ice or a Chernobyl-on-the-rocks.”

Rosatom highlighted the potential for immediate emissions reductions and cited support from nuclear advocates. It said that no nuclear material would be left in the Arctic, and that in 40 or 50 years the plant will be towed away from the site for decommissioning.

Once the Lomonosov, with its two KLT-40 reactors — similar to reactors used to power Russian icebreaker ships — is hooked up to the power grid along the Bering Strait, it will be the only floating plant of its kind in the world.

In the late 1960s and early 1970s, the U.S. planned to park a floating reactor off the coast of New Jersey, as Matt Reimann reported for Timeline. It was planned as the first in a series of floating reactors built with the idea that construction costs would drop if all the necessary skilled labor were located in one place, before the plants were shipped elsewhere. However plans for the plant were scrapped as energy became less profitable during the 1973 oil embargo.

Originally published on Live Science.

Stratolaunch Test Photos: The World’s Largest Plane in Action


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Stratolaunch Test Photos: The World’s Largest Plane in Action

 

The World’s Largest Plane

Credit: Stratolaunch System

China’s Quantum-Key Network, the Largest Ever, Is Officially Online


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China’s Quantum-Key Network, the Largest Ever, Is Officially Online

 China's Quantum-Key Network, the Largest Ever, Is Officially Online
A figure from the letter shows how the Micius satellite transfers quantum keys across vast distances.

Credit: Physical Review Letters

China has the quantum technology to perfectly encrypt useful signals over distances far vaster than anyone has ever accomplished, spanning Europe and Asia, according to a stunning new research letter.

Bits of information, or signals, pass through people’s houses, the skies overhead and the flesh of human bodies every second of every day. They’re television signals and radio, as well as private phone calls and data files.

Some of these signals are public, but most are private — encrypted with long strings of numbers known (presumably) only to the senders and receivers. Those keys are powerful enough to keep the secrets of modern society: flirty text messages, bank-account numbers and the passwords to covert databases. But they’re brittle. A sufficiently determined person, wielding a sufficiently powerful computer, could break them.

“Historically, every advance in cryptography has been defeated by advances in cracking technology,” Jian-Wei Pan, a researcher at the University of Science and Technology of China and author on this research letter, wrote in an email. “Quantum key distribution ends this battle.”

Quantum keys are long strings of numbers — keys for opening encrypted files just like the ones used in modern computers — but they’re encoded in the physical states of quantum particles. That means they are protected not only by the limits of computers but the laws of physics.

Quantum keys cannot be copied. They can encrypt transmissions between otherwise classical computers. And no one can steal them — a law of quantum mechanics states that once a subatomic particle is observed, poof, it’s altered — without alerting the sender and receiver to the dirty trick. [What’s That? Your Physics Questions Answered]

And now, according to a new letter due for publication today (Jan. 19) in the journal Physical Review Letters, quantum keys can travel via satellite, encrypting messages sent between cities thousands of miles apart.

The researchers quantum-encrypted images by encoding them as strings of numbers based on the quantum states of photons and sent them across distances of up to 4,722 miles (7,600 kilometers) between Beijing and Vienna — shattering the previous record of 251 miles (404 km), also set in China. Then, for good measure, on Sept. 29, 2017, they held a 75-minute videoconference between researchers in the two cities, also encrypted via quantum key. (This videoconference was announced previously, but the full details of the experiment were reported in this new letter.)

This long-distance quantum-key distribution is yet another achievement of the Chinese satellite Micius, which was responsible for smashing a number of quantum-networking records in 2017. Micius is a powerful photon relay and detector. Launched into low Earth orbit in 2016, it uses its fine lasers and detectors to send and receive packets of quantum information — basically, information about the quantum state of a photon — across vast stretches of space and atmosphere.

“Micius is the brightest star in the sky when it is passing over the station,” Pan wrote to Live Science. “The star is [as] green as the beacon laser [that Micius uses to aim photons at the ground]. If there is some dust in the air, you will [also] see a red light line pointing to the satellite. No sound comes from space. Maybe there are some raised by the movement of the ground station.”

Just about any time Micius does anything, it blows previous records out of the water. That’s because previous quantum networks have relied on passing photons around on the ground, using the air between buildings or fiber optic cables. And there are limits to line-of-sight on the ground, or how far a fiber-optic cable will transfer a photon without losing it.

In June 2017, Micius researchers announced that they had sent two “entangled” photons to ground stations 745 miles (1,200 km) apart. (When a pair of photons gets entangled, they affect each other even when separated by large distances.) A month later, in July, they announced that they had teleported a packet of quantum information 870 miles (1,400 km) from Tibet into orbit, meaning the quantum state of a particle had been beamed directly from a particle on the ground to its twin in space.

Both of these achievements were major steps on the road to real-world quantum-key-encrypted networks.

The new letter announces that the theory has been put into action.

Micius first encrypted two photos, a small image of the Micius satellite itself, then a photo of the early quantum physicist Erwin Schrödinger. Then it encrypted that long video call. No similar act of quantum-key distribution has ever been achieved over that kind of distance.

Already, Pan said, Micius is ready to use to encrypt more important information.

Quantum-key distribution is essentially a creative application of the so-called Heisenberg’s uncertainty principle, one of the foundational principles of quantum mechanics. As Live Science has previously reported, the uncertainty principle states that it’s impossible to fully know the quantum state of a particle — and, crucially, that in observing part of that state, a detector forever wipes out the other relevant information that particle contains.

That principle turns out to be very useful for encoding information. As the Belgian cryptographer Gilles Van Assche wrote in his 2006 book “Quantum Cryptography and Secret-Key Distillation,” a sender and receiver can use the quantum states of particles to generate strings of numbers. A computer can then use those strings to encrypt some bit of information, like a video or a text, which it then sends over a classical relay like the internet connection you’re using to read this article.

But it doesn’t send the encryption key over that relay. Instead, it sends those particles across a separate quantum network, Van Assche wrote.

In the case of Micius, that means sending photons, one at a time, through the atmosphere. The receiver can then read the quantum states of those photons to determine the quantum key and use that key to decrypt the classical message. [Album: The World’s Most Beautiful Equations]

If anyone else tried to intercept that message, though, they would leave telltale signs — missing packets of the key that never made it to the sender.

Of course, no network is perfect, especially not one based on shooting information for individual photos across miles of space. As the Micius researchers wrote, the networks typically loses 1 or 2 percent of their key on a clear day. But that’s well within what Micius and the base station can work together to edit out of the key, using some fancy mathematics. Even if an attacker did intercept and wreck a much larger chunk of the transmission, whatever they didn’t catch would still be clean — shorter, but perfectly secure enough to encrypt transmissions in a pinch. [How Quantum Entanglement Works (Infographic)]

The connection between Micius and Earth isn’t perfectly secure yet, however. As the team of Chinese and Austrian authors wrote, the flaw in the network design is the satellite itself. Right now, base stations in each linked city receive different quantum keys from the satellite, which are multiplied together and then disentangled. That system works fine, as long as the communicators trust that no secret squad of nefarious astronauts has broken into Micius itself to read the quantum key at the source. The next step toward truly perfect security, they wrote, is to distribute quantum keys from satellites via entangled photons — keys the satellites would manufacture and distribute, but never themselves be able to read.

In time, the researchers wrote, they plan to launch more quantum satellites into higher orbits — satellites that will communicate with one another and with researchers on Earth in ever-more-complex webs.

This slowly spreading, ever-more-practical quantum network will first be built for China and Europe, they wrote, “and then on a global scale.”

Originally published on Live Science.