CLOSE
Original image

What is a Supervolcano?

Original image


In Yellowstone, the rim of a supervolcano caldera is visible in the distance. Photo courtesy of the National Park Service.

In 2012, director Roland Emmerich’s love letter to the Mayan apocalypse (oh hey, wasn't that supposed to happen today?), our heroes barely manage to escape Yellowstone National Park before it explodes beneath them. This not-so-subtle sci-fi sequence is actually based on something real: Underneath Yellowstone is a supervolcano. What distinguishes this kind of volcano from regular volcanoes, and what will happen if—or when—it erupts?

Regular versus Super Volcano

There are several types of volcanoes: Cinder, composite or stratovolcanoes, shield volcanoes, and lava domes, which all rise above the earth. But supervolcanoes like the one under Yellowstone are calderas, vast sunken areas formed when the volcano expels all of its magma, and the land comes back to rest in the empty chamber. These calderas can be as big as 60 miles across (the current Yellowstone caldera, which sits on several older calderas, measures about 28 miles by 47 miles).


Click to enlarge.

When Mount St. Helens, a stratovolcano located in Washington, erupted in 1980, the event rated a 5 on the Volcanic Explosivity Index (VEI) and expelled one cubic kilometer of ash. But supervolcanoes register 8 on the VEI and typically expel ten thousand times the quantity of magma and ash expelled during the Mount St. Helens eruption. The last Yellowstone eruption, which occurred 640,000 years ago, "spewed out nearly 240 cubic miles of debris," according to the USGS.

The Yellowstone is just one of a few supervolcanoes scattered around the globe. An incomplete list includes Taupo in New Zealand, which was the most recent to erupt, about 26,000 years ago. Before that was a supereruption of Lake Toba on Sumatra, Indonesia, which occurred 69,000 to 77,000 years ago. There's a supervolcano under Pompeii, and one in Chile, too. There may be more we haven't yet discovered.

What Happens If A Supervolcano Erupts?

Below Yellowstone's surface—in some places as little as 5 or 6 miles—is a reservoir of solid rock and magma. Below that is a 45-mile-wide plume of molten rock that comes from at least 410 miles beneath the Earth surface (this is what fuels Yellowstone's incredible geysers and geothermal pools). Bob Smith, who first described Yellowstone as "a living, breathing caldera" in 1979, says in his book, Windows into the Earth, that if the caldera were to erupt, "Devastation would be complete and incomprehensible."

First there would be swarms of earthquakes, then a huge blast that would wipe Yellowstone off the map. Clouds of ash and gas would burn everything in their paths. Ash would cover most of North America, destroying food sources. Some speculate that a supereruption from the Yellowstone caldera would instantly kill 87,000 people. Others speculate that such an eruption would lower the temperature of the Earth by at least 21 degrees, and might even block out the sun.

Recently, a study determined that if or when Yellowstone next erupts, it will probably be centered in one of three parallel fault zones running north-northwest across the park.

Still, there's probably not a reason to worry. Chances are, a supereruption won't occur in our lifetimes. Number crunchers have determined that only 1.4 supereruptions occur every million years, and, according to the USGS, the chances of Yellowstone erupting are slim: just 1 in 730,000, or 0.00014 percent, a year. Sorry, conspiracy theorists. Maybe at the end of the next b'ak'tun.

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

Original image
Nick Briggs/Comic Relief
entertainment
arrow
What Happened to Jamie and Aurelia From Love Actually?
May 26, 2017
Original image
Nick Briggs/Comic Relief

Fans of the romantic-comedy Love Actually recently got a bonus reunion in the form of Red Nose Day Actually, a short charity special that gave audiences a peek at where their favorite characters ended up almost 15 years later.

One of the most improbable pairings from the original film was between Jamie (Colin Firth) and Aurelia (Lúcia Moniz), who fell in love despite almost no shared vocabulary. Jamie is English, and Aurelia is Portuguese, and they know just enough of each other’s native tongues for Jamie to propose and Aurelia to accept.

A decade and a half on, they have both improved their knowledge of each other’s languages—if not perfectly, in Jamie’s case. But apparently, their love is much stronger than his grasp on Portuguese grammar, because they’ve got three bilingual kids and another on the way. (And still enjoy having important romantic moments in the car.)

In 2015, Love Actually script editor Emma Freud revealed via Twitter what happened between Karen and Harry (Emma Thompson and Alan Rickman, who passed away last year). Most of the other couples get happy endings in the short—even if Hugh Grant's character hasn't gotten any better at dancing.

[h/t TV Guide]

SECTIONS
BIG QUESTIONS
BIG QUESTIONS
WEATHER WATCH
BE THE CHANGE
JOB SECRETS
QUIZZES
WORLD WAR 1
SMART SHOPPING
STONES, BONES, & WRECKS
#TBT
THE PRESIDENTS
WORDS
RETROBITUARIES