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M. Weiss/CfA

New "Super-Earth" Exoplanet May Have Water—and Life

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M. Weiss/CfA

A possible new Earth-like world has been found, and it’s giant, according to a study [PDF] published today in Nature. LHS 1140b, an exoplanet a mere 40 light-years away, is 40 percent larger than Earth while orbiting a tiny red dwarf star one-fifth the size of our own. That might not seem like the recipe for “Earth” or “life,” but the planet resides in its star's habitable zone, the slim "Goldilocks" orbit at which water can exist as a stable liquid. It also exhibits characteristics of a rocky world, which is significant: where there’s water and rock, there’s a possibility for life.

The world was discovered using the transit photometry method of exoplanet detection. As a planet crosses in front of a star, the star dims slightly. Think of an annular solar eclipse: When the Moon crosses in front of the Sun but is too far from the Earth to blot out the Sun entirely, the day is dimmed but isn’t plunged into darkness. The same principle applies here, though on a much finer scale. The amount the star dims also reveals its size.

So what makes this exoplanet so special? What about the TRAPPIST-1 worlds we were celebrating last month? That party might have been a bit premature. Scientists have only measured the density of one of those worlds, and turns out: It isn’t rocky. So … maybe none of the others are, either. While they’re certainly Earth-sized and in their star's habitable zone, imagining Earth without rocks is something of a challenge. LHS1140b, though, is rocks for days, and now that scientists know it's there, the plan is to study the hell out of it.

Jason Dittmann of the Harvard-Smithsonian Center for Astrophysics and lead author of the study tells mental_floss that the team studying LHS 1140b has been allocated Hubble Space Telescope time to do another transit observation. They’ve also applied for further Hubble time and x-ray telescope time in order to assess the high-energy environment the planet may be experiencing. Here on Earth, they hope also to use both Magellan telescopes at Las Campanas Observatory in Chile, and their Chilean collaborators have applied to use three of that country’s Very Large Telescopes. "So, basically, we're hoping to throw everything we have at this planet!" he says.

The James Webb Space Telescope, set to launch next year, will really unlock the mysteries of LHS 1140b. "We hope to be able to detect not just that this planet has an atmosphere but also what it's made of. In particular, [James Webb Space Telescope] may be sensitive to carbon dioxide, water, methane, and ozone," he says. The Giant Magellan Telescope and European Extremely Large Telescope, both under construction, might be able to detect molecular oxygen as well, as the strongest features of that molecule exist at more optical wavelengths. "If we can do all of these things, we might have a pretty clear picture about the atmosphere, and what's in it, and hopefully we can even say that's very similar to the Earth's."

Dittmann's Harvard colleague David Charbonneau, a co-author of the study, tells mental_floss that until James Webb launches, there’s much work to do. "First, we need to figure out the ultraviolet emission from the star," he says. "Some red dwarfs have huge amounts of UV light, which can be devastating to the atmosphere, and life! So, we are planning to use the Hubble Space Telescope to learn that. Also, there is one (and only one) good ground-based opportunity to study the planet from Chile this fall, so we are trying to have every large telescope in Chile point at the system on that night. We are calling it Transit Night." That will take place on October 26, 2017.

While ground-based observations won't be as penetrating as what the James Webb Space Telescope will be able to do, they will tell scientists if the atmosphere has, for example, lots of hydrogen and helium ("which would make the atmosphere fluffy and easy to detect," he says) and thus not Earth-like. Once the telescopes in development go online, however, there is even a chance that they can find signs of life. "[The Giant Magellan Telescope] can detect oxygen, which is an atmospheric biosignature gas," he says, though oxygen alone isn't enough. "Maybe, unlike Earth, the oxygen is made by a different process, such as UV light breaking apart water in the atmosphere. The [James Webb Space Telescope] observations will be sensitive to the other molecules—methane, water, carbon dioxide—that would allow us to know whether the oxygen really is produced by life."

LHS 1140b was first detected by Harvard’s MEarth (pronounced "mirth") project, and confirmed by the European Southern Observatory’s High Accuracy Radial velocity Planet Searcher. The planet is thought to be at least five billion years old, and its size and density suggest a dense iron core beneath its rocky surface.

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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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One Bite From This Tick Can Make You Allergic to Meat
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We like to believe that there’s no such thing as a bad organism, that every creature must have its place in the world. But ticks are really making that difficult. As if Lyme disease wasn't bad enough, scientists say some ticks carry a pathogen that causes a sudden and dangerous allergy to meat. Yes, meat.

The Lone Star tick (Amblyomma americanum) mostly looks like your average tick, with a tiny head and a big fat behind, except the adult female has a Texas-shaped spot on its back—thus the name.

Unlike other American ticks, the Lone Star feeds on humans at every stage of its life cycle. Even the larvae want our blood. You can’t get Lyme disease from the Lone Star tick, but you can get something even more mysterious: the inability to safely consume a bacon cheeseburger.

"The weird thing about [this reaction] is it can occur within three to 10 or 12 hours, so patients have no idea what prompted their allergic reactions," allergist Ronald Saff, of the Florida State University College of Medicine, told Business Insider.

What prompted them was STARI, or southern tick-associated rash illness. People with STARI may develop a circular rash like the one commonly seen in Lyme disease. They may feel achy, fatigued, and fevered. And their next meal could make them very, very sick.

Saff now sees at least one patient per week with STARI and a sensitivity to galactose-alpha-1, 3-galactose—more commonly known as alpha-gal—a sugar molecule found in mammal tissue like pork, beef, and lamb. Several hours after eating, patients’ immune systems overreact to alpha-gal, with symptoms ranging from an itchy rash to throat swelling.

Even worse, the more times a person is bitten, the more likely it becomes that they will develop this dangerous allergy.

The tick’s range currently covers the southern, eastern, and south-central U.S., but even that is changing. "We expect with warming temperatures, the tick is going to slowly make its way northward and westward and cause more problems than they're already causing," Saff said. We've already seen that occur with the deer ticks that cause Lyme disease, and 2017 is projected to be an especially bad year.

There’s so much we don’t understand about alpha-gal sensitivity. Scientists don’t know why it happens, how to treat it, or if it's permanent. All they can do is advise us to be vigilant and follow basic tick-avoidance practices.

[h/t Business Insider]