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Sean Seidell, graphic designer and flavor-visualizer, has made an infographic about just about all of the world's most wonderful things -- cheese, whiskey, coffee, beer. The next logical step, obviously, was chocolate.

Seidell spent three weeks delving into the complicated world of single-origin cacao, using information culled from Chocolate Science and Technology by Emmanuel Afoakwa, a professor of food science at the University of Ghana.

The resulting infographic is a broad overview of the four varieties of cacao -- Criollo, Forastero, their hybrid Trinitario, and Nacional -- and the countries that produce them. A Peruvian Criollo, for instance, has a fruity, winey, somewhat bitter flavor profile, whereas a Criollo from Venezuela adds a cocoa, nutty flavor into the mix of fruity and bitter. For a bright, fruity, floral flavor, you should go with a Sri Lankan Trinitario, whereas a Forastero from São Tomé and Príncipe will overwhelm you with a whirlwind of fruity, bitter, spicy, cocoa and grassy flavors.

Yes, grassy. It's apparently a much more common chocolate flavor than you'd expect, showing up in the Dominican Republic's Criollo Forastero and Ecuador's Arriba Nacional as well. If you're not quite that adventurous, stick with Forastero beans from Ghana. Cocoa and nutty flavors, no funny business.

And now that you've brushed up on your cacao flavor profiles, put down the Snickers and go get yourself some real chocolate.

This much is certain: The fabricate-at-home future has arrived, and it's here to stay. But just how far affordable 3-D printers and other personal manufacturing devices will take us, and what other devices we should expect to soon change our lives, remain unclear. If anyone has a better sense than most, however, it's Carl Bass, the CEO of Autodesk.

The $9 billion company made its mark by creating industry-standard design software called AutoCAD. And this month they partnered with MakerBot--creators of the high-res 3-D printer Replicator 2--to capture swelling numbers of potential customers equipped with 3-D printers. We chatted with Bass at the 2013 Kairos Global Summit, held at the New York Stock Exchange, to peer into his crystal ball of home fabrication.

Out of this World! Jewelry in the Space Age, an exhibition opening this weekend at the Forbes Galleries, is showing off jewelry, precious and otherwise, that's inspired by space, crafted from meteorites, and more.

Here's the idea, from guest curator Elyse Zorn Karlin:

This solid-gold replica was made by Parisian jeweler Cartier, and three editions will be shown off at the exhibition--one for each of the spacecraft's astronauts (Neil Armstrong, Buzz Aldrin, and Michael Collins). Sounds like an Oscar for space explorers.

[Daily Icon]

We've already covered two plans for a 3-D printed house, and they couldn't be more different. The first is a Mobius-strip-style building without a beginning or an ending. The second design would be made of plastic, and it looks kinda like a spider's nest. This design, the latest contender, was created by Dutch firm DUS Public Architecture, and actually looks like a relatively normal building--a cathedral, even.

Using the massive, custom-built KamerMaker printer, DUS wants to start printing the first room on-site (yes, the printer can make entire rooms) in the next six months, then print the rest of the building in pieces over the next three years. After the house is done, the firm wants to split up the interior room-by-room to create different areas for various research projects.

Any 3-D printed house is a super ambitious project, but this one might succeed before the others because it looks the least ambitious but the most thought-out. The renderings make the proposed house look how you'd expect a house to look, 3-D printed or not, and the firm's got an itemized breakdown by date of their plans for the building. And, of course, with the KamerMaker, they've got the hardware to make it happen.

[The Architect's Newspaper]

Modern-day hopheads--the beer drinkers who gleefully, obsessively seek out hoppier and hoppier brews--don't usually start out that way. Most people have a natural aversion to bitter compounds--useful for avoiding eating lethal doses of poisons in the wild. No, one must work one's way up to hops: Start off drinking beers with lower IBUs (International Bitterness Units, one measure of how bitter a beer is), be them ambers, lagers, brown ales, or stouts. Next, try a pale ale. Then try many pale ales. Then discover the IPA -- and with it, become obsessed with hop varietals such as Simcoe (piney aroma) and Amarillo (fruity aroma). Be happy with that for a while. Maybe try a double IPA (twice the malt, twice the hops as a regular IPA), which may or may not be successful, depending on whose you drink. Begin to love being punched in the face with a fist of hops. Become obsessed with IBU ratings. Buy the hoppiest beers one can find, even if they don't actually taste all that good. Despair.

Back in 2005, a pair of California-based brewers (Vinnie Cilurzo of Russian River and Matt Brynildson of Firestone Walker) came up with a tongue-in-cheek definition for this hop passion. They called it the lupulin threshold shift, describing it as "when a double IPA just isn't enough." (Lupulin glands on the hop cones hold the main hop compounds that eventually contribute flavor and bitterness to beers.) I've seen many a beer drinker ask why they feel compelled to seek out ever-hoppier beers. Could it be that their brains and tastebuds are addicted to the hop?

While pushing the hop envelope -- and one's tastebuds -- is an escalating practice, are hops actually addictive? The answer is no. You can cut hops out of your diet with no adverse physical reactions just like you can do the same for curry or bacon cheeseburgers or any number of other food items for which one occasionally develops cravings. Gustatory cravings are not the same as caffeine jags, nic fits or heroin jones. Although recent research seems to suggest that certain "psychological" addictions might be more similar to physical addictions than previously thought, the mechanism of opiate or nicotine addiction is generally quite different on a molecular level. Let's look, for example, at nicotine. The nicotine molecule binds to receptors in the brain called nicotinic acetylcholine receptors. When those receptors activate, dopamine accumulates in certain parts of the brain, which either directly or indirectly signals reward or reward expectation. Frustrated reward kicks off another biochemical pathway leading to the physical effects of withdrawal. Re-addition of the chemical quells the withdrawal, reinforcing the physical addiction. With something like a food addiction (aka compulsive overeating), the initial chemical event -- e.g. the binding of nicotine to a nicotinic receptor -- is absent. That said, a dopamine reward mechanism is still triggered, which reinforces the behavior. Further, recent research shows that compulsion -- frequently thought to be only a hallmark of the so-called psychological addictions -- actually plays a role in physical addictions as well. So, while you might be getting addicted to the alcohol in beer (another physical addiction), you're not ever going to become physically dependent on humulones.

So, what's going on with the whole hop-escalation thing, then? I've seen some scientists suggest that the culprit is sensory adaptation and habituation. Adaptation occurs when your perception of taste or smell dissipates over the course of exposure to the sensation. Adaptation happens quickly, usually over a few minutes, and reverts to the normal sensitivity within an hour or so. Habituation, on the other hand, means that for a long time after the initial exposure, sensitivity to the sensation remains diminished. Research indicates, for example, that capsaicin exposure has both an adaptation element (the heat in that salsa will only be bad for about 15 minutes), and a habituation element (for about a week afterward, that salsa will remain less "hot" to the test subject, which scientists suspect is why some people can tolerate much hotter foods than others).

I've found a fair bit of research out there on both bitter taste habituation and olfactory habituation; both kinds are important when dealing with hops, since "hoppiness" is really a mixture of an aroma experience and a bitter taste experience. In the case of olfactory adaptation and habituation, the mechanisms of change appear to be quite different. In a paper published in 2010, for example, the quick adaptation occurred mostly due to synaptic adaptation in the brain's cortex. With the long-term habituation, on the other hand, related changes occurred in the olfactory bulb rather than the brain. Anyway, so while I haven't seen much literature on hop bitterness and aroma adaptation and/or habituation, I wouldn't be surprised if there was an element to both driving the desire to drink 1,000-IBU** beers.

**It is not technically possible to brew a 1,000-IBU beer, but that doesn't stop brewers from engaging in a bit of exaggerated labeling.

In the rainforests of South America, squirrel monkeys and capybaras would never meet. While squirrel monkeys live in trees up to 60 feet high, capybaras-the world's largest rodents-dwell along river banks. But at the Beekse Bergen Safari Park in the Netherlands, the two species have shared an enclosure for eight years now, and they seem to be friends. The monkeys ride and groom the capybaras. They even eat and play together. Interspecies relationships are more frequent between captive animals, says behavioral ecologist Marc Bekoff. Because keepers feed them, they can spend time getting to know their enclosure mates instead of foraging for food. In 2005, a similar arrangement at a zoo in Japan went sour when a capybara mauled a monkey to death. But Bekoff says that, for the most part, zoos are safe environments for odd relationships.

Dear Google,

Hi.

We've noticed a lot of people are upset that you've decided to retire Google Reader and, truth be told, so are we. But, on the other hand, we do understand you are a business and have to sacrifice one product to the Fire God of Silicon Valley every second quarter or whatever.

We only ask that, before it becomes final on July 1, you at least consider shuttering one of these pretty-much-fine-but-not-as-good-as-Reader services.

All the best,

PopSci

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In 1983, the world lost one of its weirdest frogs. The gastric-brooding frog, native to tiny portions of Queensland, Australia, gave birth through its mouth, the only frog to do so (in fact, very few other animals in the entire animal kingdom do this--it's mostly this frog and a few fish). It succumbed to extinction due to mostly non-human-related causes--parasites, loss of habitat, invasive weeds, a particular kind of fungus. There were two subspecies, the northern and souther gastric-brooding frog, and they both became extinct in the mid-80s sometime.

Except--what if they didn't?

Taking place at the University of Newcastle, the quest to revive the gastric-brooding frog became known as the Lazarus Project. Using somatic-cell nuclear transfer (SCNT), a method for cloning, the project has achieved the major step forward of creating an early embryo of the extinct frog. Essentially, they found a related frog--the great barred frog, which also lives in Queensland and has cool eye markings, like it's wearing sunglasses--deactivated its eggs, and replaced them with eggs taken from the extinct frog.

Even though the gastric-brooding frog has been extinct for decades, it's possible to do this because individual specimens were kept preserved in, believe it or not, everyday deep freezers. When going through somatic-cell nuclear transfer, the eggs began to divide and form into the early embryo stage.

The embryos didn't survive much longer than that, but it was confirmed that these embryos contain genetic information from the gastric-brooding frog--that yes, in fact, they have brought it back to life. The researchers are confident that this is a "technical, not biological" problem at this stage to breed gastric-brooding frogs to adulthood. This is a big step forward for the worldwide attempts to revive extinct animals--the Lazarus Project researchers will soon meet with those working to revive the woolly mammoth, dodo, and other extinct beasties to share what they've learned.

Oh, and in case you were wondering: the gastric-brooding frog lays eggs, which are coated in a substance called prostaglandin. This substance causes the frog to stop producing gastric acid in its stomach, thus making the frog's stomach a very nice place for eggs to be. So the frog swallows the eggs, incubates them in her gut, and when they hatch, the baby frogs crawl out her mouth. How delightfully weird!

With the exception of Russian novelists, not many people can say their big break was inspired by the despair of a frost-ridden, snot-icicle-inducing winter. Yet for Kranthi Kiran Vistakula, a graduate student from Hyderabad, India, the inconvenience of the Boston cold wasn't something to shrug at -- it was a problem to fix.

While working toward a master's degree in biomedical engineering at the Massachusetts Institute of Technology, he grew increasingly annoyed by the cyclical struggle of piling on layers of clothing to combat the frigid cold on his walk to class, only to break into a sweat and peel them off the minute he stepped inside an overheated building.

To make himself more comfortable, he invented what would become ClimaCon technology, a lightweight, wearable system that can heat and cool on demand. Seven years later, his idea has gone through around 250 iterations and expanded from winter outerwear with possible military applications to coasters to keep your coffee warm, wraps that can be used in medical therapy, and maybe even a new air conditioning system for your car. Along the way, he's received an unusually large boost in funding and support from the Indian government. With technology his professors told him was thermodynamically impossible, he's now poised to capture a chunk of the U.S. market after debuting at this year's Consumer Electronics Show.

While still at MIT, Vistakula, now 33, was set on developing a jacket that could keep the wearer's body temperature at a comfortable level even when the outside temperature varied. His professors were skeptical when he told them he wanted to design a climate-controlling jacket that weighed only a little more than a pound. When he wore an early version to class, a 10-pound model equipped with heavy fans and wires, people looked at him like he was crazy. The jacket used a thermoelectric principle called the Peltier effect: when an electric current flows through two different metals connected to each other, one will become hot and the other cold.

To bring down the weight, he ditched the fans in favor of nanotechnology. He began designing ClimaCon, a patented nanotech-based cooling system based on the Peltier effect that dissipates heat without a fan, either toward your body (to keep you warm) or away from your body (to cool you off). He made a jacket with 16 small thermoelectric plates that could be arranged near large muscle groups, where blood flow and heat concentration are high. With an article of clothing no heavier than a pair of jeans, he could keep his body comfortable in outside temperatures that ranged from -50 to 50 degrees Celsius.

Even in its early stages, the product held enough promise that Vistakula put his studies on hold to pursue a startup full-time, leaving MIT only a year and a half into his degree. He had always wanted to be an entrepreneur, and he had already successfully won $3,000 in startup money from MIT business plan competitions with ClimaCon. Because he couldn't found a U.S. company on his student visa he left Cambridge in 2008 to return to India and found Dhama Innovations, where he would begin refining the technology necessary to make ClimaCon commercially viable.

"I always knew heating and cooling would have a lot of applications," he says of his initial product. "The jacket was one immediate application a lot of people liked." One initial expansion of the idea involved designing a cooling system for Russian-made missiles that don't function properly in India's intense heat, but the prototype didn't progress far.

At a time when entrepreneurship was still "very new to India," Vistakula applied for seed funding from the Department of Scientific and Industrial Research through their Technopreneur Promotion Programme, where jury member Mahesh Krovvidi took notice of his idea.

Krovvidi, the CEO of the National Design Business Incubator at the National Institute of Design in Ahmedabad, saw potential for his newly founded mentorship program to improve Vistakula's product. In addition to $110,000 in seed money from the Indian government, Vistakula received an invitation to join the incubator.

"I realized this technology would require a lot of design support," Krovvidi explains. "Our incubator was in a position to partner with the designers to make his product complete and ready for market."

In its early development at MIT, ClimaCon was a crude concept both from a technological and a design standpoint. To become market ready, Vistakula had to increase its efficiency, decrease the device's weight and design it to better conform to the human body.

Though Vistakula had initially thought the technology would be useful to the Indian army, both in terms of all-weather clothing and to cool missiles, Krovvidi urged him to look at broader applications -- for sports, outdoor adventure gear and health.

The technology has the potential to be used in a wide range of consumer products, in everything from snow boots to hot plates to cars. To narrow its focus, the company decided to focus on medical heating and cooling therapy, which uses the contrast of hot and cold to increase circulation, soothe pain and promote the healing process.

ClimaCon has four cold settings and four hot settings between 38 and 140 degrees Fahrenheit, controlled by a small remote. It's powered by cell phone batteries, and depending on the device, can run for up to four hours per charge. It can cool from room temperature to its lowest point in three seconds, and heat back up to 140 degrees Fahrenheit in 13 seconds. That makes it ideal for contrast therapy, alternating extreme temperatures to treat pain from muscle soreness and injuries. A band that can get hot and cold on-demand is far more convenient than squirming under a dripping ice pack.

According to Vistakula, the medical market in the U.S. has the advantage of high consumer awareness and already-existing distributer networks. Now roughly 80 percent of the company is devoted to the medical market.

Since his days at MIT, Vistakula and ClimaCon have continued to draw attention and gather prizes from events like the Lockheed Martin Innovator's Award, the Intel India Innovation Pioneers Challenge and the Under Armor Innovation Challenge. In 2010, Vistakula was named MIT Technology Review's "Innovator of the Year." Between government funding and prize money from business competitions (the Intel win came with $20,000), Dhama Innovations has been able to use angel investment and venture capital funding as a networking opportunity rather than a financial necessity.

After three years at the National Design Business Incubator, the five-person company had outgrown their small office space, and Vistakula relocated his headquarters to his hometown, Hyderabad, and set up an office in Boston. In January, Dhama Innovations debuted its ClimaWare Contrast Relief System -- medical heating and cooling wraps to manage back, elbow, knee and head pain -- at this year's Consumer Electronics Show. The event gave Vistakula and his team -- now a total of 18 people -- a chance to meet distributors and make sales. VentureBeat even called them one of the event's best startups.

The company has been selling some of its lower-end products, wraps that just provide heating, through doctors in India since April 2012. For his higher-end products, which are capable of both heating and cooling, Vistakula wants to expand to the U.S., where the medical device market is more advanced and stable. For now, Dhama Innovations has two U.S. distributors, and Vistakula hopes that the the medical contrast wraps will be freely available within a year, through healthcare channels like doctors and chiropractors as well as direct sales.

For now, ClimaWare products can also be bought individually online. Since the beginning of the year, Dhama Innovations has already sold $50,000 worth of climate-controlled products including jackets, dress shirts, warming coasters and body wraps, providing an extra source of revenue for the growing company.

Despite the years he's spent tweaking his technology, Vistakula says for entrepreneurs, great technology isn't really the key to a successful company. "Product positioning and product interaction -- those are the key things, not the products," he explains. Finding out what your customers really want is the challenge. "Technology is an in-house matter. It's always under your control, whereas the customers are external factors you cannot control." His approach to product testing seems to be working: He's having trouble just keeping up with demand now.

Though the Indian entrepreneurship scene is growing, Vistakula is now planning on moving to California to ease Dhama Innovations' transition into the American medical market. He may have other future applications up his sleeve as well. "I cannot do one thing and just focus on it at one time," he explains. "I need some side projects." One of these side projects is working with General Motors to possibly develop ClimaCon for use in car seats to cool your back and thighs. The other project he's working on he won't hint at, other than that it's going to be "new and cool." With ClimaCon, it'll probably have the potential to be hot, too.

Sam Bompas and Harry Parr are a breed unto themselves; young British purveyors of culinary spectacle whose most recent book, Feasting, includes recipes for simple dishes like ham covered in glitter, as well as elaborations entailing octopus tentacles, diethyl ether, and explosives.

In the past, they've constructed events like a lake of alcoholic punch you can row across (indoors) and a room full of vaporized gin and tonic. Now, in a new installation at King's College London, they've built a tornado out of whirling whisky mist.

The tornado represents

It may not be as dramatic as Theo Gray's fire tornado, featured in our current issue, but it's more intoxicating.

[Via Designweek]

Want to win this artistic Baarbarian illustration on a T-shirt? It's easy! The rules: Follow us on Twitter (we're @PopSci) and retweet our This Week in the Future tweet. One of those lucky retweeters will be chosen to receive a custom T-shirt with this week's Baarbarian illustration on it, thus making the winner the envy of friends, coworkers and everyone else with eyes. (Those who would rather not leave things to chance and just pony up some cash for the T-shirt can do that here.) The stories pictured herein:

• 9 Reasons To Avoid Sugar As If Your Life Depended On It
• The Science Of Soda Sizes
• Trained Soviet Attack Dolphins With Head-Mounted Guns Are On The Loose
• Dad Of The Year Hacks 'Donkey Kong' So His Daughter Can Play The Princess And Save Mario
• The Sistine Chapel Is Getting A High-Tech Bug-Proofing
• 5 Weird Things Associated With Getting Fat

And don't forget to check out our other favorite stories of the week:

• How To Build A 2,073-Foot Skyscraper
• The Maddening Science Of Finding A Job
• 7 Signs SimCity's Creators Are Environmental Activists
• War In Infrared And Other Amazing Images From This Week
• Samsung Announces Galaxy S 4; It Has All Of The Features
• Cyber Attacks Are America's Top Security Threat. That's Better News Than It Sounds
• The Best RSS Readers To Use Now That Google Reader Is Dead
• Should Kickstarter Be Collecting Your Money For Hollywood Movie Studios?
• 15 Incredible Images Of Futuristic Skyscrapers
• ALMA, Earth's Largest Telescope, Is Officially Open For Business
• The U.S. Army's Ambitious Fight Against PTSD
• Photos From 11 Of The World's Coolest Nuclear-Monitoring Stations
• Wearable Computers Could Help Build A Better You
• BeerSci: Are Hops Addictive?

People can reliably read a dog's facial expressions, suggesting humans are finely tuned to detect emotions even in other creatures. Behavioral scientists have long known that people can accurately read other humans' emotions, but this study suggests our empathy extends to other members of the animal kingdom.

While a Ph.D student at Walden University in Florida, Tina Bloom worked with Harris Friedman and a dog named Mal at the Pennsylvania Department of Corrections. Mal, a 5-year-old Belgian shepherd and trained police dog, was subjected to a variety of stimuli, and the researchers took pictures of his reactions.

For instance, in one experiment the researchers praised him, trying to elicit a happy reaction; Mal looked at the camera with his ears erect and tongue lolling. Then they reprimanded him, and Mal's ears flattened, he looked down and his eyes became mournful. They used a jack-in-the-box to surprise him; foul-tasting medicine to disgust him; nail trimmers to strike fear into his heart; and so on. One of the researchers even pretended to be a criminal, and Mal got angry. Then the team showed 50 volunteers photographs of these reactions, and asked them to categorize his emotions.

It was easy to spot happiness, with 88 percent of volunteers correctly pegging Mal's doggy smile. Fright and sadness were a bit harder to register, at 45 percent and 37 percent, respectively. Disgust was the hardest to figure out, with just 13 percent of people able to determine what Mal's sour face meant.

In an interesting twist, people who don't own dogs were sometimes a better judge of a dog's emotions. This might indicate that dog owners convince themselves their pets are not angry or disgusted--they're just playing. It could also mean that understanding a dog's emotions is a natural ability, not a learned one. I think I can read many of my dog's emotions, which is easy because they follow a spectrum of general nervousness at all times. Below, my border collie Sadie registers what I view as anticipation, frustration and "squirrel."

Bloom told the Telegraph she wanted to continue the research to determine whether this emotional connection extends to all mammals, or just dogs, which have evolved alongside humans for 100,000 years. Her dissertation is published in Behavioral Processes.

New software under development could let more smartphones, tablets and security cameras take people's pulses by recording their faces for 5 seconds.

Japanese technology company Fujitsu announced today it's working on the pulse-recording technology, which could help people track their own health, or spot suspicious reactions at concerts or at the airport, the company said in a statement. Fujitsu wants to have the tech ready for practical use within a year.

The new software uses cameras in devices to watch for the subtle color changes in people's faces when blood rushes in with every pump of the heart. A recent iPhone app from MIT works similarly. MIT has also developed software that exaggerates that color change so it's visible to the naked eye.

It's hard to tell exactly where people would use this. An easy pulse-checker for workouts would be cool, but MIT's Cardiio app already works for that. The Fujitsu statement suggests 9-to-5ers track their pulse throughout the day, but I've never been curious about my pulse during meetings or email-composing.

Tracking people at security checkpoints sounds interesting, but the technology would probably have to clear stringent tests showing its effectiveness before any country or agency would want to install something new and train all its employees for pulse-monitoring. At first glance, the technology sounds like it could mark too many people as suspicious for airport security. What if people have elevated heart rates just because they're nervous about traveling, for example? We'll see how much Fujitsu can do in a year.

[Fujitsu]

On Saturday, 3-D printed gunsmith Defense Distributed published on Facebook a photograph of its newly acquired Title 7 Federal Firearms License. The Title 7 license allows Defense Distributed to manufacture and sell ammunition and firearms.

We've covered Defense Distributed here before, most recently last month when founder Cody Wilson fired 600 rounds with a 3-D printed receiver. The licensing brings Defense Distributed clearly in line with the law--a curious move for an organization that delights in questioning legal boundaries. From its mission statement:

Public statements such as these call into question the logic of much gun regulation. The 600-round lower receiver test, after all, was in direct response to congressional talk about ammunition magazine-size restrictions. Questioning the law doesn't require directly challenging it, and Defense Distributed's new license acknowledges that reality for now.

Wilson says he will not start making and selling guns until he receives additional licensing.

Stay tuned on Popular Science for more from Wilson himself.

Lots of astronauts living on the International Space Station are prolific tweeters and photographers. But every few missions or so, someone comes along who really gets it, and shares the experience of life in space better than most. Like the station's newly minted commander, Chris Hadfield. Go here to follow him on Twitter.

He has been on the station since December, but took the helm late last week. Hadfield held his first press conference as commander on Monday morning. Half of his interview was in French--oh, Canada--but the parts in English were a reminder of why he's been so much fun to follow on Twitter and SoundCloud. He played a stirring rendition of "Danny Boy" on St. Patrick's Day, for instance.

If he were to take someone on a tour, he would bring them first to the ISS cupola, the big window on the world, "so they could truly see our Earth," he said, "the power of it ... the size of it, the beauty of it, and the inherent fragility of it. When you see the blackness and emptiness of space... and the one layer of onion skin atmosphere that surrounds our planet, it becomes so vivid in your mind. It permanently changes your thinking."

Hadfield is the first Canadian commander of the ISS, a source of enormous pride for our neighbor to the north. His leadership marks only the second time ever that the 12-year-old station has not been helmed by someone either American or Russian.

"It's a huge honor and a privilege for me, but also for all the people at the Canadian Space Agency and for my entire country," he said.

Hadfield took over before past commander Kevin Ford and cosmonauts Oleg Novitskiy and Evgeny Tarelkin departed for Earth last Friday. He'll lead a three-man crew until NASA's Chris Cassidy and cosmonauts Pavel Vinogradov and Alexander Misurkin arrive later in March. Hadfield, astronaut Thomas Marshburn and cosmonaut Roman Romanenko have been on station since Dec. 21 and will come home in May.

Monday mornings pretty much always make me feel like blowing things up. So watching videos about things blowing up -- or people blowing things up -- seems to be a perfect way to ease into the work week.

Happily for my now-improving mood, demolition experts demolished a 1930s-era steel bridge along US 281 in Marble Falls, Texas over the weekend, and someone was there to film it. I love how the first two passes of the video -- real-time and semi-slo-mo -- it's difficult to see exactly how the demo goes. But the third time, look closely under the bridge. You can totally see the detonator cords burning up ahead of the ignition of the shaped charges that brought the trusses down. The video also clearly demonstrates the difference between the speed of light in air and the speed of sound in air -- the flashes from the charges are long gone by the time the sound waves make it to the filming location. According to a fact sheet from the Texas Department of Transportation, steel from the bridge will be recycled into "beautification projects." I read elsewhere that it'll be turned into sculptures or other pieces of public artwork.

Here's another angle, with even better slo-mo.

This isn't the first time we've written about bridge demos. A couple of years ago, we ran a Megapixels about a bridge demolition in Ohio and West Virginia (the bridge spanned the Ohio River). During reporting, we learned that it required some 153 pounds of explosive to bring down that suspension bridge. The demolition occurred in multiple phases: cut the suspension cables, destroy the roadway and then topple the towers. To my glee, that demolition has a slow-motion video as well.

I totally want to bring a Phantom HD camera to one of these demolitions. I bet the resultant footage would be totally killer.

The Mars rover Curiosity's home in Gale Crater may be dry now, but it was definitely wet long, long ago, scientists said Monday. Curiosity has seen evidence of wet conditions all around the area where it drilled last month and has been parked in safe mode for a while.

The watery conditions extend beyond the site of Curiosity's drilling, according to NASA.

Scientists working with Curiosity keep noticing some interesting coloration in the rocks in Yellowknife Bay, where the rover has been exploring. Some of the rocks contain fissures, and bright veins crisscross their surfaces. Using a sensitive neutron instrument and the rover's infrared cameras, scientists were able to study these veins in great detail, and determine they contain signs of water.

"With Mastcam, we see elevated hydration signals in the narrow veins that cut many of the rocks in this area," said Melissa Rice of Caltech. "These bright veins contain hydrated minerals that are different from the clay minerals in the surrounding rock matrix."

That's interesting because it lends further credence to the idea that Gale Crater could have been hospitable for life. Curiosity's science team announced last week that past environmental conditions there were favorable for microbes. Now it looks like this is true across a broad swath of the area. It's also worth noting that this water apparently didn't change the rocks' chemical composition very much.

The rover's Dynamic Albedo of Neutrons instrument, or DAN, detected hydrogen in water molecules that are bound up inside minerals in the rock. There's a lot of variation in its location, but there is more in Yellowknife Bay than earlier on Curiosity's traverse, according to Maxim Litvak, deputy principal investigator for the DAN instrument at the Science Research Institute in Moscow.

Once Curiosity gets rolling again, it will cross another potentially interesting geologic boundary where scientists could find even more water evidence, Litvak said.

"We are looking forward for the next drive," he said in a news conference.