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The Time We Found Pyramids on Mars

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Image credit: NASA/JPL-Caltech

Mars has long fascinated people. One of the few objects in the night sky to show a visible color and the only one that wandered, it was a natural draw. As astronomy blossomed and scientists realized that it was another world, visionaries began to speculate about life there.

The first good telescopic observations revealed a world with definite features, areas of light and dark which could be continents and oceans. In 1877, Giovanni Schiaparelli took advantage of a particularly favorable opposition (when Mars and Earth are on the same side of the Sun, and Mars appears high in the night sky) and drew a map of the planet. In keeping with the belief that the dark regions were oceans, when he saw dark lines across the lighter areas, he dubbed them "canali," Italian for "channels."

Map of Mars by Giovanni Schiaparelli

Note that although the "rivers" or "canals" are not real, he did see many things that are real -- the Hellas basin is a gigantic impact crater, and the "lake" that he depicts in "Thaumasia felix" is actually the caldera of Olympus Mons.

American astronomer Percival Lowell believed that Schiaparelli had discovered artificial canals. Lowell became a major early proponent for the idea of a complex civilization on Mars. He persisted even when later observers failed to find the canals, demonstrated the likelihood of them being an optical illusion, and even when spectrographic data revealed that Mars was not really a very hospitable place -- cold, dry, and with an atmosphere too thin to maintain liquid water. The idea persisted occasionally in science fiction until 1965, when Mariner 4 flew by Mars.

In its brief flyby, it revealed a Mars that appeared as dead and hostile as the Moon -- barren and pocked with craters. Furthermore, the canals were clearly not present.

Map of Martian Canals by Percival Lowell

Mariner 4 image of Mars, showing moon-like craters

The idea of life on Mars fell largely out of favor as a result of this, but interest in Mars remained. Though the canals were obviously not real, speculation turned from present Martians to Martians past. If there was no civilization now, was it possible there had been in the past? After Mariner 4, Mariners 6 and 7 also flew by, largely confirming the lifeless image. But then that all changed.

Mariner 9 arrived in Mars orbit on November 14, 1971. It was followed within a month by the Soviet probes Mars 2 and Mars 3. On arrival, the probes discovered a Mars transformed: a vast dust storm completely masked the planet. Eventually, the dust settled, revealing a world of wonders previously unseen: staggeringly huge extinct volcanoes, a tremendous canyon system named for the probe (Valles Marineris), dry riverbeds, fog, clouds . . . and something else. On February 8, 1972, Mariner 9 returned an image of what looked an awful lot like pyramids in a region called Elysium Planitia:

Mariner 9 image of Elysium Planitia, showing pyramid-shaped structures

Could it be? Had there really been intelligent life on Mars, which had built pyramids eerily similar to the Egyptian pyramids at Giza? Some other vaguely artificial-looking objects were also observed, and piqued a bit of interest, but none more than the pyramids. That was nothing compared to what would come in 1976, though.

In 1976, two "flagship class" probes arrived at Mars: Viking 1 and Viking 2. Each was an orbiter/lander pair. Their orbiters surveyed the planet in much more detail than Mariner 9 had been able to achieve. In addition to obtaining better resolution images of the pyramids at Elysium Planitia, they also found some more in a region called Cydonia Mensae. As exciting as the first pyramid discovery had been, this really took off in the public imagination, for in addition to what seemed like a complex of pyramids, there was a gigantic face.

The "Face on Mars," photographed by Viking 1; note that the black spots are data loss, not real objects

A consultant at Goddard Space Flight Center happened to see the images and found his fame in them. His name was Richard Hoagland, and he was to become the most ardent proponent of the Face on Mars. He described the pyramids as a buried city, and the Face as a crumbling monument akin to the Sphinx in Egypt.

There was no new data on these features for some time. No new missions were greenlit until Mars Observer, which ended in disaster when the probe suddenly ceased transmitting shortly before orbital insertion. It wasn't until September 12, 1997, that a new spacecraft arrived at Mars: Mars Global Surveyor. It eventually imaged both Elysium and Cydonia, and the results were disappointing for anyone hoping to find evidence of life, although many refused to give up the faith. Mars Odyssey 2001, Mars Express, and Mars Reconnaissance Orbiter have mapped the planet in ever increasing detail, and the features have proven to be disappointingly natural.

Elysium pyramid, photographed by Mars Reconnaissance Orbiter

It does look like a pyramid, doesn't it? But then, so does this:

Even if there aren't really alien-built structures on its surface, Mars still conceals a lot of mysteries. It boasts the largest volcanoes in the solar system by a huge margin, and also the largest canyon. It is smaller than Earth, but has the same land surface area as Earth's continents. It has weather, including dust devils and gigantic dust storms. It has ice caps made of a mixture of water ice and frozen carbon dioxide, and water not only flowed in the past, but appears to be sometimes able to flow in the present as well. And who knows? Perhaps by the end of the century, some of us will be living there. And then we can build our own pyramids!

Note: Some of you may have seen the Doctor Who serial "Pyramids of Mars," featuring Tom Baker and Elizabeth Sladen as they combat animated mummies and a vengeful Egyptian god. The serial ended with a final battle under the pyramids of Mars. More on that episode and other Doctor Who stories ripped from the headlines here.

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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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Live Smarter
Working Nights Could Keep Your Body from Healing
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The world we know today relies on millions of people getting up at sundown to go put in a shift on the highway, at the factory, or in the hospital. But the human body was not designed for nocturnal living. Scientists writing in the journal Occupational & Environmental Medicine say working nights could even prevent our bodies from healing damaged DNA.

It’s not as though anybody’s arguing that working in the dark and sleeping during the day is good for us. Previous studies have linked night work and rotating shifts to increased risks for heart disease, diabetes, weight gain, and car accidents. In 2007, the World Health Organization declared night work “probably or possibly carcinogenic.”

So while we know that flipping our natural sleep/wake schedule on its head can be harmful, we don’t completely know why. Some scientists, including the authors of the current paper, think hormones have something to do with it. They’ve been exploring the physiological effects of shift work on the body for years.

For one previous study, they measured workers’ levels of 8-OH-dG, which is a chemical byproduct of the DNA repair process. (All day long, we bruise and ding our DNA. At night, it should fix itself.) They found that people who slept at night had higher levels of 8-OH-dG in their urine than day sleepers, which suggests that their bodies were healing more damage.

The researchers wondered if the differing 8-OH-dG levels could be somehow related to the hormone melatonin, which helps regulate our body clocks. They went back to the archived urine from the first study and identified 50 workers whose melatonin levels differed drastically between night-sleeping and day-sleeping days. They then tested those workers’ samples for 8-OH-dG.

The difference between the two sleeping periods was dramatic. During sleep on the day before working a night shift, workers produced only 20 percent as much 8-OH-dG as they did when sleeping at night.

"This likely reflects a reduced capacity to repair oxidative DNA damage due to insufficient levels of melatonin,” the authors write, “and may result in cells harbouring higher levels of DNA damage."

DNA damage is considered one of the most fundamental causes of cancer.

Lead author Parveen Bhatti says it’s possible that taking melatonin supplements could help, but it’s still too soon to tell. This was a very small study, the participants were all white, and the researchers didn't control for lifestyle-related variables like what the workers ate.

“In the meantime,” Bhatti told Mental Floss, “shift workers should remain vigilant about following current health guidelines, such as not smoking, eating a balanced diet and getting plenty of sleep and exercise.”