CLOSE
Original image

The Arecibo Message

Original image

Let's say you're a human with a big radio transmitter, who wants to send a message to the putative aliens out there light-years away, listening by their radio receivers. What would your message say? How would you format it, since you don't have any concept of the recipient's language or cognitive abilities? What would be most interesting and salient to a completely unknown civilization? Given the limits of the exercise, there are only a few known factors about the recipient: you can assume that the recipient is technologically advanced enough to have built a radio, received the message, and recognized that it's actually a message rather than noise. But aside from that, a world of questions surround the issue.

Carl Sagan dramatized this problem (in reverse) in his 1985 book Contact. His novel was likely based on his own experience more than ten years earlier, he was faced with the challenge in real life. In 1974, astrophysicist Frank Drake proposed sending just such a message -- and Sagan was recruited to help write and format it.

Drake, Sagan, and others developed a message to be broadcast by the Arecibo radio telescope, using a mathematical scheme they hoped could be decoded by an alien civilization. The message itself consisted of just 1,679 binary digits (1's and 0's). The digits were broadcast one per second, on November 16, 1974. The telescope was pointed at the M13 cluster, some 25,000 light years away. The broadcast was never repeated -- hopefully someone will be listening when the message arrives in deep space (for what it's worth, by the time 25,000 years pass, M13 will no longer be where it was when we sent the message -- so our transmission will miss whoever lives there). But let's get back to brass tacks -- what did the message say? Well, using binary encoding, the message carried the information below. (A colorized version of the message, rendered as blocks, is also presented at left.)

  1. the numbers one (1) through ten (10)
  2. the atomic numbers of the elements hydrogen, carbon, nitrogen, oxygen, and phosphorus, which make up deoxyribonucleic acid (DNA)
  3. the formulas for the sugars and bases in the nucleotides of DNA
  4. the number of nucleotides in DNA, and a graphic of the double helix structure of DNA
  5. a graphic figure of a man, the dimension (physical height) of an average man, and the human population of Earth
  6. a graphic of Earth's solar system
  7. a graphic of the Arecibo radio telescope and the dimension (the physical diameter) of the transmitting antenna dish

It's clear that the transmission was more a symbolic event than an actual attempt at communication -- if we were attempting to communicate, we'd probably send the message more than once, or to more than one spot in the sky. (A 1999 press release said as much, with Cornell Professor Donald Campbell explaining, "It was strictly a symbolic event, to show that we could do it.") But the possibility remains that some intelligence could intercept the message and perhaps decode it -- and maybe, just maybe, reply. In August of 2001, a crop circle appeared in farmland near the Chibolton radio telescope in Hampshire, UK. Known to crop circle aficionados as the Arecibo reply, the pattern looked like a modified version of the original transmission, showing a big-headed alien and adding silicon to the list of elements, among other changes. While it's clearly a hoax, it's a clever one, and took a lot of work to put together.

Further reading: the Arecibo message at Wikipedia, a mathematical explanation of the message, and more on Frank Drake.

So let's hear it: if you were sending a message into the unknown depths of space, what would you say?

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