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Science Channel/BBC/Patrick Toselli

Tonight: The Challenger Disaster on Science and Discovery Channels

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Science Channel/BBC/Patrick Toselli

Space fans, set your DVRs! The Challenger Disaster premieres tonight—Saturday, November 16 from 9-11pm ET/PT. It's airing on both Science Channel and Discovery Channel at the same time.

When I heard there would be a movie about the Challenger disaster, I was intrigued—I assumed it would be another documentary, explaining O-rings, launch temperatures, management issues, and so on. (I have been mildly Challenger-obsessed since the day it blew up, and more so after studying the disaster in college.) But when I heard the movie was a drama starring William Hurt as Richard Feynman?! I was hooked.

The Challenger Disaster is Science Channel's first drama. It covers the investigation into the catastrophic loss of the Space Shuttle Challenger on January 28, 1986, when all seven crew members died shortly after Challenger lifted off. I remember watching on TV as the craft burst apart, leaving twisting trails of smoke. After the disaster, President Reagan created the Rogers Commission to determine why Challenger failed.

Chairman Rogers (BRIAN DENNEHY). Photo courtesy of Discovery Channel/BBC.

The Rogers Commission and its report were a huge deal, partly because of tensions within the commission itself. Chairman Rogers and physicist Richard Feynman butted heads, and Feynman ended up writing his own appendix to the report, in which he detailed problems with the management culture at NASA. Feynman opened with this little zinger (emphasis added):

It appears that there are enormous differences of opinion as to the probability of a failure with loss of vehicle and of human life. The estimates range from roughly 1 in 100 to 1 in 100,000. The higher figures come from the working engineers, and the very low figures from management. What are the causes and consequences of this lack of agreement? Since 1 part in 100,000 would imply that one could put a Shuttle up each day for 300 years expecting to lose only one, we could properly ask "What is the cause of management's fantastic faith in the machinery?"

Feynman also wrote about the experience in his book, What Do You Care What Other People Think? In The Challenger Disaster, we see a dramatization of that work—a reasonably faithful record of what happened, but employing dramatic license to add tension here and there. The movie is interesting both for newcomers and people who are familiar with the story, though the latter might find Hurt's portrayal of Feynman a little more sober than what we might expect.

(L-R) General Kutyna (BRUCE GREENWOOD), Chairman Rogers (BRIAN DENNEHY), Sally Ride (EVE BEST). Photo courtesy of Science Channel/BBC/Patrick Toselli.

The Challenger Disaster deals with a grim, technical topic without getting mired in the grimness nor the technical bits—but it does give us enough of each to understand what's happening. The most interesting parts of the story are when we come to understand the politics of the situation. In those moments, we see the tension between Feynman's scientific instincts and the political maelstrom that surrounds him. The man had guts. The weakest moments are the repeated (and frankly ham-fisted) nods to Feynman's cancer. It's hard to go ten minutes in this movie without another reference to Feynman's mortality and his refusal to accept it; while this is probably largely true, it plays on the screen as hero worship. But all in all, this is a terrific movie, particularly for a TV movie. Tune in tonight.

A companion documentary (that I have not yet seen) airs on Monday, November 18 at 10pm ET/PT on Science Channel. Entitled Feynman: The Challenger, it covers Feynman's life and work, including his involvement with The Manhattan Project. I'll be tuning in for that one too.

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iStock // Ekaterina Minaeva
Man Buys Two Metric Tons of LEGO Bricks; Sorts Them Via Machine Learning
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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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200 Health Experts Call for Ban on Two Antibacterial Chemicals
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In September 2016, the U.S. Food and Drug Administration (FDA) issued a ban on antibacterial soap and body wash. But a large collective of scientists and medical professionals says the agency should have done more to stop the spread of harmful chemicals into our bodies and environment, most notably the antimicrobials triclosan and triclocarban. They published their recommendations in the journal Environmental Health Perspectives.

The 2016 report from the FDA concluded that 19 of the most commonly used antimicrobial ingredients are no more effective than ordinary soap and water, and forbade their use in soap and body wash.

"Customers may think added antimicrobials are a way to reduce infections, but in most products there is no evidence that they do," Ted Schettler, science director of the Science and Environmental Health Network, said in a statement.

Studies have shown that these chemicals may actually do more harm than good. They don't keep us from getting sick, but they can contribute to the development of antibiotic-resistant bacteria, also known as superbugs. Triclosan and triclocarban can also damage our hormones and immune systems.

And while they may no longer be appearing on our bathroom sinks or shower shelves, they're still all around us. They've leached into the environment from years of use. They're also still being added to a staggering array of consumer products, as companies create "antibacterial" clothing, toys, yoga mats, paint, food storage containers, electronics, doorknobs, and countertops.

The authors of the new consensus statement say it's time for that to stop.

"We must develop better alternatives and prevent unneeded exposures to antimicrobial chemicals," Rolf Haden of the University of Arizona said in the statement. Haden researches where mass-produced chemicals wind up in the environment.

The statement notes that many manufacturers have simply replaced the banned chemicals with others. "I was happy that the FDA finally acted to remove these chemicals from soaps," said Arlene Blum, executive director of the Green Science Policy Institute. "But I was dismayed to discover at my local drugstore that most products now contain substitutes that may be worse."

Blum, Haden, Schettler, and their colleagues "urge scientists, governments, chemical and product manufacturers, purchasing organizations, retailers, and consumers" to avoid antimicrobial chemicals outside of medical settings. "Where antimicrobials are necessary," they write, we should "use safer alternatives that are not persistent and pose no risk to humans or ecosystems."

They recommend that manufacturers label any products containing antimicrobial chemicals so that consumers can avoid them, and they call for further research into the impacts of these compounds on us and our planet.