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    Designing Underwater Robots for Deeper Dives

    In May, the remotely operated underwater vehicle Nereus descended 10,000m to the bottom of the Kermadec Trench, one of the ocean’s deepest, and never came back. It’s believed that Nereus—a hybrid remotely operated vehicle, or ROV, that could also operate autonomously—likely imploded. The pressure at such depths can be as great as 16,000 pounds per square inch.

    What’s weird is that Nereus was *designed* to withstand such pressure. That’s what made it unique. Unlike most other ROVs, which get their buoyancy from a material called syntactic foam, the Woods Hole Oceanographic Institute (WHOI), which designed and built Nereus, opted for a radical new design involving hundreds of ceramic spheres instead.

    Photo credit: WHOI

    While we still don’t really know how or why Nereus failed–it completed numerous previous dives, some to deeper depths, without issue–there’s no denying that its novel design allowed Nereus to dive deeper, be built lighter, and stay underwater longer than probably any other ROV in existence. So, implosion aside, why aren’t we yet building more ROVs like Nereus—even the ones that aren’t destined for places as deep or pressures as intense as those of the Kermadec Trench?

    Putting anything underwater requires a delicate balance between buoyancy and weight, explains Andy Bowen, director of the WHOI’s National Deep Submergence Facility, and maintaining that balance becomes more difficult the deeper you go down.

    “You want the vehicle to be slightly positively buoyant, or at least neutrally buoyant. So all the stuff that weighs something has to be offset by something that doesn’t weigh as much–or, in fact provides, a buoyancy offset,” Bowen says. “You can broadly divide these things into parts that float or parts that don’t.”

    Syntactic foam block machined for ROV use.

    Obviously, batteries, cameras, lights and motors are the things that don’t, and it’s the job of people like Bowen to make them float. Traditionally, manufacturers have used a material known as syntactic foam, which is composite material filled hollow microscopic glass bubbles. These bubbles lower the material’s density, making it buoyant. It’s flexible, well-understood, and has been in use for decades. When you look at a photo of a typical ROV, it's the brightly colored material mounted to the top of the robot's frame. "You can make syntactic foam to go just about anywhere you want it to go,” says Bowen, “but with a price.”

    A Glimpse Inside the World's Deepest Caves

    I absolutely loved this New Yorker piece by Burkhard Bilger about Bill Stone's expedition to the Chevé cave system near Oaxaca Mexico. Chevé is one of the deepest cave systems in the world, and explorers are constantly pushing the boundaries to find the ends of the system. At this level, spelunking requires high proficiency in dozens of skills, including climbing and scuba diving. It's long, but definitely worth a Saturday morning read.

    The Teddy Bear and Our Shifting Relationship with the Natural World

    "In 1902, President Theodore Roosevelt legendarily spared the life of a black bear - and prompted a plush toy craze for so-called "teddy bears." Writer Jon Mooallem digs into this story and asks us to consider how the tales we tell about wild animals have real consequences for a species' chance of survival - and the natural world at large." Mooallem is the author of Wild Ones, a great book about the eccentric cultural history of Americans and our relationship with wild animals and the natural world. Mooallem also performed this lovely reading from his book in an episode of 99 Percent Invisible.

    The Pontiac Silverdome, Vacant Since 2012

    "The Pontiac Silverdome is a vacant sports stadium, formerly the home of the Detroit Lions football team, and the Detroit Pistons basketball team. Other major events included Wrestlemania III, which set a world record for attendance at an indoor event. The Lions left the stadium in 2002, after which some concerts and sports events were held. The Silverdome has been vacant since 2012, and the contents are being auctioned off." (h/t Laughingsquid)

    The Moons of Mars Explained

    Kurzgesagt is a wonderful YouTube channel that explains basic and controversial scientific concepts in concise animated videos. It was created by a team of designers from Munich, and the show's narration gives it a more than just a little bit of a Hitchhiker's Guide to the Galaxy vibe. Their videos this month explain facts about the moons in the solar system, and this video explaining the Stock Exchange is one of my favorites.

    Tested Explains: Earth's Magnetic Field Wonkyness

    The Earth’s magnetic field is acting pretty wonky right now. That may be an indicator of big changes to come. Or it could just be business as usual. The truth is that the most consistent thing about our magnetic field is that it’s inconsistent over short periods of time (like the human lifespan). But when scientists look at it across millennia, they recognize that its behavior is actually fairly easy to predict if they can just get an accurate measurement. So what, exactly, is going on with the modern magnetic field? I asked Scott Bogue, a geologist at Occidental College in Los Angeles, and one of the leading experts on Earth’s geomagnetism. Turns out, was a bit of a controversial question.

    First, some background. If you know about the science, it makes sense that our field isn’t the most stable force on the planet. After all, it’s created by conditions in the most volatile place on Earth. The planet’s core is a spinning, stirring, moving glob of really excellent electricity-conducting liquid metal (iron-nickel alloy, to be exact). All the extreme heat energy down there, and the energy created by gravity, gets converted into the movement of the fluid. And energy from that fluid momentum gets converted into electromagnetic energy, which emanates from the core as our magnetic field.

    The field surrounds the Earth and extends out into space (far enough that it encompasses all our orbiting satellites, but not so far that it reaches the moon). Its most important role is that it blocks particles that shoot down to earth from the sun (solar wind) and faraway stars (cosmic rays) by pushing them away from the Earth’s center and directing them towards the poles. That’s why the Northern and Southern Lights, created when incoming particles from the sun interact with Earth’s atmosphere, aren’t visible to most of the planet’s population. If we didn’t have the magnetic field, we’d see lights all over the Earth.

    We won’t have Earth's magnetic field forever.

    We won’t have the field forever. As the core cools and eventually stops spinning, the field will go away. Mars, for example, has a solid, cold core and no field (all of our outer planets -- Jupiter, Saturn, Uranus, and Neptune -- still have fields). Scientists aren’t sure what, exactly, will happen to Earth when our field finally goes away. They think all that solar wind and cosmic rays bombarding us might create a bunch of small holes in our ozone layer at low latitudes. At the very least, we’d probably get a lot more skin cancer.

    So here’s where the controversy comes in.

    Awesome Jobs: Meet Linda Gormezano, Polar Bear Poop Tracker

    Understanding the changing dietary habits of polar bears is the key to seeing how climate change and shrinking polar ice is affecting their lifestyles. And the best way to know what’s happening with their diet? Look at their poop, of course! Linda Gormezano, an ecologist at the American Museum of Natural History in New York City, has trained her dog Quinoa to help her find the best samples left by bears as they cross the frozen Canadian tundra. Gormezano chatted with us about why poop is such a useful scientific specimen and what it’s like to spend months living in a camp in the heart of polar bear country.

    A grouping of adult male polar bears along the coast of western Hudson Bay in summer (photo credit: Robert F. Rockwell)

    What’s ecology and how does it apply to polar bear research?

    Ecology is the interaction between animals and the environment. What we’re studying is how polar bears behave on land with respect to available food -- what they eat and where they eat it. What I’m particularly interested in is how they hunt other animals and how the calories they gain from consuming them are going to affect their annual energy budget as their access to ice becomes more limited.

    We collect scat and hair samples non-invasively. After consuming food on the ice or on land some bears leave scat. Also some bears rest right along the coast, bedding down in sand and grass where they leave hairs behind, while others head further inland and leave hair in dens.

    Linda Gormezano and her dog, Quinoa. (photo credit: AMNH)

    What, exactly, is an energy budget?

    Nobody really knows how often polar bears in western Hudson Bay capture seals, but they get a certain amount of energy from consuming seals they hunt out on the ice and that energy allows them to survive on land for 4-5 months each year. If the ice melting earlier each year causes polar bears to have less time to hunt seal pups in spring, they may be taking in fewer calories over the course of the year.

    What we want to know is, now that they’re eating more of certain types of foods on land, what kind of energetic benefits might polar bears be experiencing? Up until now many have thought what they were eating on land wasn’t really helping them at all. To evaluate this, we are examining the energetic costs and benefits of capturing and consuming those foods as well as how often the behavior occurs. Only then can we determine whether these foods could help alleviate nutritional deficits that polar bears may come ashore with.

    In Brief: ISS to Test NASA's Hydroponics Pod

    SpaceX's third contracted cargo run was supposed to launch on Monday--a Dragon capsule ferrying 2.5 tons of supplies to the International Space Station. But a helium leak in the first stage of SpaceX's Falcon 9 rocket has delayed that launch until the end of this week. Among the tools, equipment, and food supplies being sent to the ISS are a new batch of experiments to join the over 100 already being conducted at any time on board the station. One notable new experiment is Veggie, NASA's prototype of an expandable plant chamber to grow lettuce seedlings in space. These plants will be grown on "pillows" in the device, which expands to 12x15-inches, the largest plant growth chamber yet sent to space. Astronauts will test the culinary and health potential of the space lettuce, and NASA also expects the experiment to have psychological benefits. Space gardening could be a legitimate pastime for astronauts.

    Norman
    Awesome Jobs: Meet Ruddy Mell, Fire Starter (for Science)

    If you want to understand how fire works, then you have to burn stuff. That’s where Ruddy Mell comes in. He’s a research combustion engineer and physicist at the U.S. Forest Service’s Pacific Wildland Fire Sciences Lab. Mell’s job is to work with teams of fire experts to create controlled burns, collect all the data they can, and then build physics-based models that can predict what could happen when seriously dangerous fires burn out of control. Mell talked with us about why our current wildfire models are so insufficient and how they go about trying to control the world’s most unpredictable element out in the field.

    Why do we need to study wildfires?

    At least three reasons. Two of them are kind of combined. They have to do with fires in the wildland and urban interface, where wildland vegetation is adjacent to where people live and fire causes damage to homes and roads and power lines and cell towers -- anything that people have built that causes enough damage that the consequences need to be addressed.

    The other problem is smoke. That’s a significant problem. Even if it doesn’t burn buildings the smoke is a problem if people are downwind. The health effect has been shown to cause increased hospital visits for respiratory problems. In some parts of the country, the southeast in particular where there are a lot of old people that are retired, it can be a big problem.

    Also in the southeast US the vegetation tends to grow back very quickly, so they have to deal with this smoke issue because the vegetation is there to burn. One of the ways they deal with fires there is to do fuel treatments, where fuel is vegetation. They’ll burn it periodically just to keep it down so it will be easier to contain if there’s a wildfire. They’re limited in doing prescribed fires because of all the people around. They want to do this to keep it safe, but it’s hard to do.

    So the wildland fire problem is a fire problem, a vegetation problem, and smoke problem. To address the problem you have to think about all that. When modelling comes in, you need models for fire and better models for smoke.

    The purpose of these research burns is to provide data sets for model testing and validation and development. The best example of a model that’s used by people everyday are weather models. Imagine the world if we couldn’t look up the forecast. You can’t use experiments alone to help with weather predictions. Suppose you go out and measure temperature and wind at some site, there’s no guarantee it will be like that a year from now. You need models to help predict out into the future.

    Photographing All of the World's Coral Reefs

    How do you understand global change of a system that’s underwater and impossible to photograph from above? Build a giant submersible camera system controlled by expert dive photographers, of course.

    The world’s reef systems are deteriorating. Corals are going away at a rate of about 1 - 2 percent every year. Some areas are harder hit than others. In the last 27 years, the Great Barrier Reef has lost 53 percent of its corals and the Caribbean has lost 80 percent. That’s a big deal because reef systems are basically cities for fish. One quarter of all the ocean’s life makes their home there. If the ocean’s corals disappear then much of the life in the ocean disappears too. For humans, that means we can no longer depend on reef systems for food, protection from weather, tourism, and medicine.

    So, we know reefs are important. And we know they’re deteriorating. What we don’t have is a visual understanding of how these reef systems are changing and any capability to compare changes to themselves or each other over time. To change that, professional underwater photographers have gotten together with ocean scientists to create the Global Reef Record -- a world-wide Google Maps-like photographic index of all of the coral systems in the entire world.

    “We’re creating a global baseline,” says Richard Vevers, executive director of the survey. “We’ve been travelling around the world using a standard protocol for collection imagery, which allows us to do a global comparison.”

    In order to accurately capture every reef on earth with consistency and 360-degree panoramic views, Vevers, who has a background in professional underwater photography, had to engineer and build a special camera. “Initially it came from an understanding of underwater photography, which is very different. We looked at taking the Google Streetview camera underwater, but we needed much wider angle lenses and we needed to be able to take shots in low visibility and low light. We also needed change exposure as we were moving without having to access the camera.”

    The solution was to build the camera completely from scratch and then mount it on an underwater scooter. The entire $50,000 system is manipulated by a waterproofed tablet, with specially designed apps, that can be controlled by divers who move a magnetic mouse that operates a button inside the tablet’s glass box.

    The Magnified World, Up Close

    The human eye is an incredible biological machine, but it has its limits. One of them is scale. There’s a whole world of beauty and surprises lurking underneath our eyes, and all we have to do is blow it up a little. In this feature, we’ll share amazing looks at ten common and not so common substances magnified hundreds of times.

    Awesome Jobs: Meet Kayla Iacovino, Trekker Volcanologist

    North Korea has a volcano. About a millennium ago it had one of the largest eruptions in Earth’s history. You probably didn’t know. And that’s OK. Because North Korea is so closed off to outsiders, most people (even some scientists) had no idea. But science is really good at overcoming political roadblocks and recently a team of researchers made their way into the country to get a closer look at their active volcanic peak. Kayla Iacovino, a volcanologist and experimental petrologist on the team, chatted with us about how North Korean scientists differ from their Western counterparts and it was like to be the only American--and the only woman--trekking through the Democratic People’s Republic of Korea.

    First of all, what the heck is an experimental petrologist?

    A petrologist is a type of geologist that looks at the origins of rocks. Petra means rock. I specifically study the origins of volcanic rocks. I take rocks that I find in the field and I recreate the conditions in which they were formed. So essentially I make mini-magma chambers in the lab.

    How do you do that?

    I take rocks that I find in the field and I recreate the conditions in which they were formed. So essentially I make mini-magma chambers in the lab.

    So, we have these big machines that essentially take a rock and put it under very high pressure and high temperature, which simulates the conditions in a magma chamber. Bubbles form and crystals grow. By looking at the chemistry we can understand the processes that happen in magma chambers to cause eruptions. It’s a field of research most people don’t know exist.

    In order to say something about the real volcanic system, a specific one, we have to be able to have some kind of basic understanding of the volcano before starting the experiments. We have to go to the field and look at the rocks. The techniques are similar to structural geology. We look at the geometry of the rocks and how they’re related spatially and we can make hypotheses about the chemistry and then we can test them in the lab.

    What exactly do you learn from reverse engineering the lava?

    That part comes when we’re analyzing the rocks. We see what crystals are there and its chemical composition. We can make a hypothesis about the conditions under which it formed. And then we test the hypothesis by putting it under those conditions to see if what comes out looks like the rock we started with.

    We can say: These are the conditions that it must have been under when it was in the volcano.

    How Plate Tectonics Affects Google Maps

    We all know that the Earth is moving around the Sun within our solar system. We all know that the Earth is rotating as it completes its orbit. And we even know that the Earth's surface isn't completely stationary. Plates gradually shift and drift apart and together. Earthquakes can move tectonic plates by several feet. But we rarely ever think of how these types of motion actually affect us. And they definitely do, as Scientific American discovered when asking this question: "What happens to Google Maps when tectonic plates move?"

    Turns out Google Maps, Google Earth, and other GPS and mapping systems are in a constant state of inaccuracy. They can only be so accurate, anyway--GPS systems can often only pinpoint your location down to a few yards, and Google Maps uses cell tower triangulation to hone in on that initial range radius represented by a blue circle. So they're not perfectly accurate to begin with, and on top of that, the map data they're based on is imperfect, too.

    Image credit: George Musser/Scientific American

    "For the most part, misalignments don’t represent real geologic changes, but occur because it’s tricky to plop an aerial or orbital image onto the latitude and longitude grid," Scientific American explains. "The image has to be aligned with reference points established on the ground." But those reference points aren't always perfect, either. NGS, the National Geodetic Survey, has left markers scattered around the country as GPS reference points, but they weren't always placed accurately, and they don't have to budget to check all of them.

    And then things get really complicated, because there's not just one end-all, be-all latitude and longitude grid to go off of.

    Awesome Jobs: Meet Doug Daly, Tree-Climbing Botanist

    If you want to find new species of plant life in the world, you have to get out and look for it. That means trekking slowly through jungles and forests--and spending a lot of time staring through binoculars at leaves, fruits, and flowers. New York Botanical Garden curator of Amazonian botany, Doug Daly, specializes in plants of the Amazon region. Specifically he spends a lot of time in Brazil and, most recently, Colombia. He chatted with us about what it’s like to identify new plant species in regions of the world that aren’t always so friendly to humans.

    Photo courtesy Doug Daly.

    Why do you study forests?

    Most people wouldn’t understand the thrill you get from being a taxonomist. I can’t separate it from the motive for becoming one. There’s a mindset for people who do systematics. As one of my old professors once said: “There are two kinds of people. Those who ask: ‘How does it work?’ And those who ask: ‘What is it?’”

    "Figuring out what things are is a complicated process. We don’t separate that from how things are related to each other."

    Figuring out what things are is a complicated process. We don’t separate that from how things are related to each other. The reason I go to places I go, to the tropics, is that’s where the species are. You’re looking for quantity and amazing mega-diversity, so traveling to those areas is kind of decided for you.

    What I’m doing right now is working on two big projects in the Brazilian Amazon that involve forest management. There’s been progress made in sustainable logging and there’s also a national forest inventory going on in Brazil. Although loggers might follow the correct procedures in practice, between 50 and 70 percent of the species are misidentified. So people have no clue about what we’re actually cutting down.

    There are practices where you can minimize the impacts on the forest, but if you don’t know what the trees are you’re kind of hamstrung.

    Celebrating Unusual Maps: The Winning Dymaxion Redux and Cahill's Butterfly

    Earlier this year we wrote about the revival of Buckminster Fuller's Dymaxion map, which has long been a favorite of triangle-loving cartographers. The Buckminster Fuller Institute held a contest for map lovers to submit a Dymax Redux design, reinterpreting the classic shape of the Dymaxion with a new visual appearance. The Dymaxion unfolds the globe into a series of triangles, designed to preserve the size and shape of the Earth's landmasses. The winner of the contest was the Dymaxion Woodocean World, a gorgeous woodcut Fuller map.

    The Dymaxion competition has also revived a bit of a cartographer competition, as Wired describes in Projection Smackdown: Cahill's Butterfly vs. the Dymaxion Map. The Dymaxion map is presented as a more accurate competitor to the popular Mercator projection, which distorts the sizes of continents. But the lesser-known Cahill Butterfly may be more accurate still.

    Cahill "proposed skinning the globe into eight triangular lobes, a method invented by Leonardo Da Vinci," Wired writes. "Rather than arrange them into a clover, as Da Vinci did, Cahill made a butterfly shape. He was interested in balance, and obsessed with his projection’s aesthetic. And his math was not too shabby either. The lobes – also called gores – are each exactly 90 degrees wide and run 10,000 km along the edge. There is practically no distortion along the edges of each lobe. The lines of latitude and longitude shrink towards the middle of each lobe. The overall effect is a map that can be scaled to any size, and errors that are easy to calculate and correct."

    Image via geographer-at-large.blogspot.com.

    Fuller's Dymaxion map presents the world from an uncommon vantage point. There's no "right" way to look at the map, nothing that suggests North America should be "above" South America, and so on. Wired points out one problem that the Dymaxion map has that Cahill's butterfly avoids, however.

    "Take a look at the United States on the Fuller map," Wired writes. "See the diagonal line that bisects the country? Notice the graticules? They run away from the seam at different angles, a pattern that repeats itself across the entire map. Every facet of the Dymaxion map has a different pattern of longitude and latitude. There isn’t a single large landmass on the planet that’s free from bent meridians and broken parallels."

    Neither map is exactly great for navigation, but the butterfly map at least preserves longitude and latitude. The Dymaxion Redux competition helped a new audience appreciate Fuller's map; maybe someday, someone will do the same for Cahill's butterfly.

    Scientific Mysteries We’re No Closer To Solving

    It seems like just about every day we read about a new breakthrough that shakes the world of science to the core. But, that said, there are some things that we’re still totally stumped on. Today, we’ll spotlight ten scientific mysteries that people have been working on for generations and we’re no closer to answering. It's stuff like this that keeps us curious about the world.

    Flowing Lava is Mesmerizing and Terrifying

    Volcano enthusiast Bryan Lowry made a series of hikes up Hawaii's Kilauea Volcano in the first half of this year to document the flow of lava over the Pu’u O’o vent that has been continuously erupting for 30 years. He shot dozens of short videos with his Nikon D800 and a GoPro camera, showing the lava cover the trails and trees that he would never be able to visit again in future hikes. The footage is mesmerizing, and more startling is the audio of the lava up close. (It reminds me of this Perry Bible Fellowship comic.) He's disabled embedding of most of his videos (except this one shot with a GoPro), but you can watch all of Lowry's videos on his Vimeo page, including this recent one of flowing lava engulfing a can of Chef Boyardee ravioli.

    New Theory Suggests Life on Earth Began with Meteors

    I like to imagine life on Earth began as it's depicted in Star Trek: The Next Generation--compounds in a puddle of goo colliding to form the first proteins, as Patrick Stewart stands around looking vaguely confused. A new theory about the beginnings of life on Earth, as reported by Phys.org, is actually pretty similar--minus Patrick Stewart.

    ""When the Earth formed some 4.5 billion years ago, it was a sterile planet inhospitable to living organisms," says paleontologist Sankar Chatterjee. "It was a seething cauldron of erupting volcanoes, raining meteors and hot, noxious gasses. One billion years later, it was a placid, watery planet teeming with microbial life – the ancestors to all living things."

    Chatterjee thinks he's figured out the sequence of events that took Earth from sterile dead zone to oceanic paradise. Meteorites were the key. Chatterjee divides the history of life's beginnings into four stages: cosmic, geological, chemical and biological. In the cosmic stage, 3.8 - 4.1 billion years ago, meteorites pounded the Earth--we can still see the damage they inflicted in craters on the moon and other planets. When giant meteorites cracked through the planet's crust, they loosed geothermal vents. They also left behind the building blocks of life, and in Greenland, Australia, and South Africa, environmental conditions were perfect for life to form.

    Image credit: CBS Home Video

    "Because of Earth's perfect proximity to the sun, the comets that crashed here melted into water and filled these basins with water and more ingredients," writes Phys.org. "This gave rise to the geological stage. As these basins filled, geothermal venting heated the water and created convection, causing the water to move constantly and create a thick primordial soup."

    At this point, the scene was very much like it was depicted in The Next Generation's finale. Convective currents from geothermal vents incubated organic molecules. The first RNA and proteins formed in the craters left behind by meteor strikes. This was the chemical stage. Chatterjee also believes that an older hypothesis about the primordial soup, from professor David Deamer, was correct--fatty lipid materials brought with the meteor strike at some point encapsulated the RNA and proteins, binding them together.

    After that, it still took millions of years for cells to begin to form and replicate. And that, says Chatterjee, is life. Pretty simple stuff, huh?