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7 Close Calls in the Nuclear Age

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Here's a formula for fun: Arm two superpowers to the teeth with thousands of nuclear warheads. Make sure they are deeply hostile and suspicious of each other. Now, cut off diplomatic communication, stir in about 50 smaller countries with their own agendas on each side, and you've got yourself a cold war!

1. Suez Crisis

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On November 5, 1956, during the Suez crisis, the North American Aerospace Defense Command (NORAD) received warnings that seemed to indicate that a large-scale Soviet attack was under way: a Soviet fleet was moving from the Black Sea to a more aggressive posture in the Aegean, 100 Soviet MiGs were detected flying over Syria, a British bomber had just been shot down in Syria, and unidentified aircraft were in flight over Turkey, causing the Turkish air force to go on high alert. All signs pointed to the ominous, except that, not long after, each of the four warnings was found to have a completely innocent explanation. The Soviet fleet was conducting routine exercises, the MiGs were part of a normal escort—whose size had been exaggerated—for the president of Syria, the British bomber had made an emergency landing after mechanical problems, and, last but not least, the unidentified planes over Turkey? Well, they turned out to be a large flock of swans.

2. SAC-NORAD Communication Failure

On November 24, 1961, all communication links between the U.S. Strategic Air Command (SAC) and NORAD suddenly went dead, cutting off the SAC from three early warning radar stations in England, Greenland, and Alaska. The communication breakdown made no sense, though. After all, a widespread, total failure of all communication circuits was considered impossible, because the network included so many redundant systems that it should have been failsafe. The only alternative explanation was that a full-scale Soviet nuclear first strike had occurred. As a result, all SAC bases were put on alert, and B-52 bomber crews warmed up their engines and moved their planes onto runways, awaiting orders to counterattack the Soviet Union with nuclear weapons. Luckily, those orders were never given. It was discovered that the circuits were not in fact redundant because they all ran through one relay station in Colorado, where a single motor had overheated and caused the entire system to fail.

3. U2 Spy Plane Accidentally Violates Soviet Airspace

U2 spy planes were high-altitude aircraft that took pictures of the Soviet Union with extremely powerful long-distance telephoto lenses. During the Cuban Missile Crisis of 1962, U2 pilots were ordered not to fly within 100 miles of the Soviet Union to avoid antagonizing the Soviets. However, on October 26, 1962, a U2 pilot flying over the North Pole made a series of navigational errors because the shifting lights of the aurora borealis prevented him from taking accurate readings with his sextant. As a result, he ended up flying over the Chukotski Peninsula in northern Siberia, causing the Soviets to order a number of MiG interceptors to shoot his plane down immediately. Instead of letting him be shot down, however, the United States responded quickly by sending out F-102A fighters armed with nuclear missiles to escort the U2 back to American airspace and prevent the MiGs from following it. Unbelievably, the tactic worked. Even more amazing: the decision whether to use their nuclear missiles was left to the American pilots, and could have easily resulted in a nuclear conflict.

4. When Camping, Make Sure to Hide Your Nuclear Weapons

On October 25, 1962, again during the Cuban Missile Crisis, a security guard at an air base in Duluth, Minnesota, saw a shadowy figure scaling one of the fences enclosing the base. He shot at the intruder and activated an intruder alarm, automatically setting off intruder alarms at neighboring bases. However, at the Volk Field air base in Wisconsin, the Klaxon loudspeaker had been wired incorrectly, and instead sounded an alarm ordering F-106A interceptors armed with nuclear missiles to take off. The pilots assumed that a full-scale nuclear conflict with the Soviet Union had begun. The planes were about to take off when a car from the air traffic control tower raced down the tarmac and signaled the planes to stop. The intruder in Duluth had finally been identified: it was a bear.

5. A Terrifying Crash

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On January 21, 1968, fire broke out on a B-52 carrying a nuclear payload near Greenland, forcing the crew to bail out. The unmanned plane then crashed about seven miles from the early warning radar station in Greenland. The damage done could have been remarkable. The plane exploded, as did the explosives surrounding the radioactive core of the nuclear weapons (which require conventional explosives to detonate). Given the state of nuclear weapons technology at the time, this type of unintentional detonation of conventional first-stage explosives could have theoretically triggered the second-stage fission reaction, resulting in a nuclear explosion. Luckily for the world, it didn't. The resulting explosion would have not only severed regular communications between the early warning station and NORAD, it would have also triggered an emergency alarm based on radiation readings taken by sensors near the station. The only conclusion at NORAD headquarters, in this grisly hypothetical but very plausible scenario, would have been that the Soviets were launching a preemptive nuclear strike, and the United States would have responded in kind.

6. Comp Fear

On November 9, 1979, four command centers for the U.S. nuclear arsenal received data on their radar screens indicating that the Soviet Union had launched a full-scale nuclear first strike on the United States. Over the next six minutes, planes were launched and nuclear missiles initialized for an immediate retaliatory strike. The president's National Emergency Airborne Command Post—an armored jumbo jet with radiation shielding and advanced communications capabilities, meant to allow the president to remain in contact with the government and armed forces during a nuclear war—was also launched, though curiously without the president aboard. However, the alarm was canceled because no sensors or satellites detected an actual Soviet missile launch. The alarm had been caused by computer software used for training exercises depicting a nightmare scenario Soviet first strike. Senator Charles Percy, who happened to be at NORAD headquarters during this event, said the reaction was one of overwhelming panic and terror. Justifiably so.

7. Comp Fear, Part 2

Electronic displays at NORAD, the SAC, and the Pentagon included prominent, highly visible numeric counters showing the number of enemy nuclear missiles detected. They normally displayed four zeros—"0000"—indicating that no nuclear missiles had been launched. However, on June 3, 1980, at 2:25 in the morning, the counters started randomly substituting the number "2" for "0." As a result, crews manning bombers carrying nuclear weapons were ordered to begin to warm up their engines, Minuteman missiles were initialized for launch, and airborne command posts were also launched. It was determined that this first event was a false alarm, but three days later it happened a second time—causing the entire emergency response procedure to start rolling once again. The problem was eventually traced back to a single faulty computer chip combined with faulty wiring.

This article was excerpted from our book Forbidden Knowledge: A Wickedly Smart Guide to History's Naughtiest Bits.

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Man Buys Two Metric Tons of LEGO Bricks; Sorts Them Via Machine Learning
May 21, 2017
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iStock // Ekaterina Minaeva

Jacques Mattheij made a small, but awesome, mistake. He went on eBay one evening and bid on a bunch of bulk LEGO brick auctions, then went to sleep. Upon waking, he discovered that he was the high bidder on many, and was now the proud owner of two tons of LEGO bricks. (This is about 4400 pounds.) He wrote, "[L]esson 1: if you win almost all bids you are bidding too high."

Mattheij had noticed that bulk, unsorted bricks sell for something like €10/kilogram, whereas sets are roughly €40/kg and rare parts go for up to €100/kg. Much of the value of the bricks is in their sorting. If he could reduce the entropy of these bins of unsorted bricks, he could make a tidy profit. While many people do this work by hand, the problem is enormous—just the kind of challenge for a computer. Mattheij writes:

There are 38000+ shapes and there are 100+ possible shades of color (you can roughly tell how old someone is by asking them what lego colors they remember from their youth).

In the following months, Mattheij built a proof-of-concept sorting system using, of course, LEGO. He broke the problem down into a series of sub-problems (including "feeding LEGO reliably from a hopper is surprisingly hard," one of those facts of nature that will stymie even the best system design). After tinkering with the prototype at length, he expanded the system to a surprisingly complex system of conveyer belts (powered by a home treadmill), various pieces of cabinetry, and "copious quantities of crazy glue."

Here's a video showing the current system running at low speed:

The key part of the system was running the bricks past a camera paired with a computer running a neural net-based image classifier. That allows the computer (when sufficiently trained on brick images) to recognize bricks and thus categorize them by color, shape, or other parameters. Remember that as bricks pass by, they can be in any orientation, can be dirty, can even be stuck to other pieces. So having a flexible software system is key to recognizing—in a fraction of a second—what a given brick is, in order to sort it out. When a match is found, a jet of compressed air pops the piece off the conveyer belt and into a waiting bin.

After much experimentation, Mattheij rewrote the software (several times in fact) to accomplish a variety of basic tasks. At its core, the system takes images from a webcam and feeds them to a neural network to do the classification. Of course, the neural net needs to be "trained" by showing it lots of images, and telling it what those images represent. Mattheij's breakthrough was allowing the machine to effectively train itself, with guidance: Running pieces through allows the system to take its own photos, make a guess, and build on that guess. As long as Mattheij corrects the incorrect guesses, he ends up with a decent (and self-reinforcing) corpus of training data. As the machine continues running, it can rack up more training, allowing it to recognize a broad variety of pieces on the fly.

Here's another video, focusing on how the pieces move on conveyer belts (running at slow speed so puny humans can follow). You can also see the air jets in action:

In an email interview, Mattheij told Mental Floss that the system currently sorts LEGO bricks into more than 50 categories. It can also be run in a color-sorting mode to bin the parts across 12 color groups. (Thus at present you'd likely do a two-pass sort on the bricks: once for shape, then a separate pass for color.) He continues to refine the system, with a focus on making its recognition abilities faster. At some point down the line, he plans to make the software portion open source. You're on your own as far as building conveyer belts, bins, and so forth.

Check out Mattheij's writeup in two parts for more information. It starts with an overview of the story, followed up with a deep dive on the software. He's also tweeting about the project (among other things). And if you look around a bit, you'll find bulk LEGO brick auctions online—it's definitely a thing!

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8 Common Dog Behaviors, Decoded
May 25, 2017
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Dogs are a lot more complicated than we give them credit for. As a result, sometimes things get lost in translation. We’ve yet to invent a dog-to-English translator, but there are certain behaviors you can learn to read in order to better understand what your dog is trying to tell you. The more tuned-in you are to your dog’s emotions, the better you’ll be able to respond—whether that means giving her some space or welcoming a wet, slobbery kiss. 

1. What you’ll see: Your dog is standing with his legs and body relaxed and tail low. His ears are up, but not pointed forward. His mouth is slightly open, he’s panting lightly, and his tongue is loose. His eyes? Soft or maybe slightly squinty from getting his smile on.

What it means: “Hey there, friend!” Your pup is in a calm, relaxed state. He’s open to mingling, which means you can feel comfortable letting friends say hi.

2. What you’ll see: Your dog is standing with her body leaning forward. Her ears are erect and angled forward—or have at least perked up if they’re floppy—and her mouth is closed. Her tail might be sticking out horizontally or sticking straight up and wagging slightly.

What it means: “Hark! Who goes there?!” Something caught your pup’s attention and now she’s on high alert, trying to discern whether or not the person, animal, or situation is a threat. She’ll likely stay on guard until she feels safe or becomes distracted.

3. What you’ll see: Your dog is standing, leaning slightly forward. His body and legs are tense, and his hackles—those hairs along his back and neck—are raised. His tail is stiff and twitching, not swooping playfully. His mouth is open, teeth are exposed, and he may be snarling, snapping, or barking excessively.

What it means: “Don’t mess with me!” This dog is asserting his social dominance and letting others know that he might attack if they don’t defer accordingly. A dog in this stance could be either offensively aggressive or defensively aggressive. If you encounter a dog in this state, play it safe and back away slowly without making eye contact.

4. What you’ll see: As another dog approaches, your dog lies down on his back with his tail tucked in between his legs. His paws are tucked in too, his ears are flat, and he isn’t making direct eye contact with the other dog standing over him.

What it means: “I come in peace!” Your pooch is displaying signs of submission to a more dominant dog, conveying total surrender to avoid physical confrontation. Other, less obvious, signs of submission include ears that are flattened back against the head, an avoidance of eye contact, a tongue flick, and bared teeth. Yup—a dog might bare his teeth while still being submissive, but they’ll likely be clenched together, the lips opened horizontally rather than curled up to show the front canines. A submissive dog will also slink backward or inward rather than forward, which would indicate more aggressive behavior.

5. What you’ll see: Your dog is crouching with her back hunched, tail tucked, and the corner of her mouth pulled back with lips slightly curled. Her shoulders, or hackles, are raised and her ears are flattened. She’s avoiding eye contact.

What it means: “I’m scared, but will fight you if I have to.” This dog’s fight or flight instincts have been activated. It’s best to keep your distance from a dog in this emotional state because she could attack if she feels cornered.

6. What you’ll see: You’re staring at your dog, holding eye contact. Your dog looks away from you, tentatively looks back, then looks away again. After some time, he licks his chops and yawns.

What it means: “I don’t know what’s going on and it’s weirding me out.” Your dog doesn’t know what to make of the situation, but rather than nipping or barking, he’ll stick to behaviors he knows are OK, like yawning, licking his chops, or shaking as if he’s wet. You’ll want to intervene by removing whatever it is causing him discomfort—such as an overly grabby child—and giving him some space to relax.

7. What you’ll see: Your dog has her front paws bent and lowered onto the ground with her rear in the air. Her body is relaxed, loose, and wiggly, and her tail is up and wagging from side to side. She might also let out a high-pitched or impatient bark.

What it means: “What’s the hold up? Let’s play!” This classic stance, known to dog trainers and behaviorists as “the play bow,” is a sign she’s ready to let the good times roll. Get ready for a round of fetch or tug of war, or for a good long outing at the dog park.

8. What you’ll see: You’ve just gotten home from work and your dog rushes over. He can’t stop wiggling his backside, and he may even lower himself into a giant stretch, like he’s doing yoga.

What it means: “OhmygoshImsohappytoseeyou I love you so much you’re my best friend foreverandeverandever!!!!” This one’s easy: Your pup is overjoyed his BFF is back. That big stretch is something dogs don’t pull out for just anyone; they save that for the people they truly love. Show him you feel the same way with a good belly rub and a handful of his favorite treats.

The best way to say “I love you” in dog? A monthly subscription to BarkBox. Your favorite pup will get a package filled with treats, toys, and other good stuff (and in return, you’ll probably get lots of sloppy kisses). Visit BarkBox to learn more.

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