October 1, 2013
Last Tuesday, a 7.7-magnitude earthquake hit Pakistan, causing widespread destruction, the creation of a new island off the country’s coastline and at least 515 deaths.
Of course, there’s nothing we can do to prevent such disasters—earthquakes result from the shifting and collision of enormous, continent-scale tectonic plates over which we have no control. If we know a massive quake is about to strike, though, there may be measures we can take to better protect ourselves.
But how could we possibly know when a quake is about to hit? Seismologists are extremely good at characterizing the overall hazards that those living in fault zones face, but they’re far away from being able (and may never have the ability) to predict exactly when an earthquake will strike.
Undeterred, several different teams of scientists are hatching plans for a new kind of solution. And the key to their success may may be the smartphone in your pocket.
Their idea takes advantage of the fact that most new smartphones include a tiny chip called an accelerometer. These chips measure the movement of the phone in three directions (up-down, left-right, and backward-forward) to customize your experience as you use the phone—for example, rotating the display if you turn the device.
As it happens, seismometers (the large, expensive instruments used by geologists to detect and measure earthquakes) do essentially the same thing, albeit with much more accuracy. Still, the tiny accelerometers we already carry around with us all the time could allow scientists to gather much more real-time data than is currently available—there are countless times more smartphones than seismometers, they’re much cheaper and they’re already deployed in a wide range of locations—if they can actually measure earthquake movement with sufficient precision.
Recently, Antonino D’Alessandro and Giuseppe D’Anna, a pair of seismologists at Italy’s Istituto Nazionale di Geofisica e Vulcanologia, set out to resolve this question. To assess the accelerometers—specifically, the LIS331DLH MEMS accelerometer used in iPhones—the duo placed five iPhones on a vibrating table in a variety of positions (flat, angled on top of a wedge-shaped piece, and vertical) and compared the data they recorded with a professional-quality earthquake sensor for reference.
Their results, published Sunday in the Bulletin of the Seismological Society of America, showed that the iPhone accelerometers performed even better than they expected. “When we compared the signals, we pleasantly surprised by the result—the recordings were virtually identical,” D’Alessandro says. “An accelerometer that costs a few dollars was able to record acceleration with high fidelity, very similar to a professional accelerometer that costs a few thousand.”
There are some limitations: the iPhone accelerometers aren’t as sensitive to weak vibrations, so during the tests, they were only able to record movements that correspond to earthquakes that would register as magnitude 5 or higher. But ”these limits will be overcome in the near future,” says D’Alessandro. “Because these chips are widely used in laptops, games controllers and mobile phones, research into improving them is going on around the world.”
The next step would be developing software to allow normal users to harness these accelerometers’ capabilities, turning their smartphones into mobile earthquake sensing systems. Last December, Berkeley researchers announced plans to develop an app that would allow users to donate their accelerometer data to earthquake research. Stanford’s Quake-Catcher Network and Caltech’s Community Seismic Network—both of which use small purpose-built seismometers that are distributed to volunteers and plugged into their computers—could serve as a model for this sort of network.
Once in place, the network would be able to gather a huge amount of data from thousands of geographically-dispersed users, allowing researchers to see how quakes move with finer resolution. If enough phones are on this network, emergency workers may be able to quickly gauge where they could most efficiently devote their time after a quake hits.
But how do you go from documenting earthquakes to warning people about when dangerous shaking will occur? As The Atlantic points out, the key is that earthquakes are actually comprised of two types of waves that ripple through the earth: P-waves, which arrive first and are difficult for humans to sense, and S-waves, which typically come a few seconds later and cause the majority of the physical damage.
If we had software installed on our phones that automatically detected strong P-waves and sounded an alarm, we might have a few scant seconds to take cover before the S-waves hit (officials recommend dropping to the ground, huddling under a stable table or desk and getting away from windows and doors). It’s not much, but in some cases, a just a few crucial seconds of warning could make all the difference.
September 26, 2013
Some 46 Martian days after landing on Mars in August 2012, after traveling nearly 1,000 feet from its landing site, Curiosity came upon a pyramid-shaped rock, roughly 20 inches tall. Researchers had been looking for a rock to use for calibrating a number of the rover’s high-tech instruments, and as principal investigator Roger Wiens said at a press conference at the time, “It was the first good-size rock that we found along the way.”
For the first time, scientists used the rover’s Hand Lens Imager (which takes ultra-high resolution photos of a rock’s surface) and the Alpha Particle X-ray Spectrometer (which bombards a rock with alpha particles and X-rays, kicking off electrons in patterns that allow scientists to identify the elements locked within it). They also used the ChemCam, a device that fires a laser at a rock and measures the abundances of elements vaporized.
Curiosity, for its part, commemorated the event with a pithy tweet:
I did a science! 1st contact science on rock target Jake. Here’s an action shot pic.twitter.com/pzcgH6Bk
— Curiosity Rover (@MarsCuriosity) September 22, 2012
A year later, the Curiosity team’s analysis of the data collected by these instruments, published today in Science, shows that they made a pretty lucky choice in finding a rock to start with. The rock, dubbed “Jake_M” (after engineer Jake Matijevic, who died a few days after Curiosity touched down), is unlike any rock previously found on Mars—and its composition intriguingly suggests that it formed after molten rock cooled quickly in the presence of underground water.
The new discovery was published as part of a special series of papers in Science that describe the initial geologic data collected by Curiosity’s full suite of scientific instrumentation. One of the other significant findings is a chemical analysis of a scoop of Martian soil—heated to 835 degrees Celsius inside the Sample Analysis at Mars instrument mechanism—showing that it contains between 1.5 and 3 percent water by weight, a level higher than scientists expected.
But what’s most exciting about the series of findings is the surprising chemical analysis of Jake_M. The researchers determined that it is likely igneous (formed by the solidification of magma) and, unlike any other igneous rocks previously found on Mars, has a mineral composition most similar to a class of basaltic rocks on Earth called mugearites.
“On Earth, we have a pretty good idea how mugearites and rocks like them are formed,” Martin Fisk, an Oregon State University geologist and co-author of the paper, said in a press statement. “It starts with magma deep within the Earth that crystallizes in the presence of one to two percent water. The crystals settle out of the magma, and what doesn’t crystallize is the mugearite magma, which can eventually make its way to the surface as a volcanic eruption.” This happens most frequently in underground areas where molten rock comes into contact with water—places like mid-ocean rifts and volcanic islands.
The fact that Jake_M closely resembles mugearites indicates that it likely took the same path, forming after other minerals crystallized in the presence of underground water and the remaining minerals were sent to the surface. This would suggest that, at least at some time in the past, Mars contained reserves of underground water.
The analysis is part of a growing body of evidence that Mars was once home to liquid water. Last September, images taken by Curiosity showed geologic features that suggested the one-time presence of flowing water at the surface. Here on Earth, analyses of several meteorites that originated on Mars have also indicated that, at some point long ago, the planet held reserves of liquid water deep underground.
This has scientists and members of the public excited, of course, because (at least as far as we know) water is a necessity for the evolution of life. If Mars was once a water-rich planet, as Curiosity’s findings increasingly suggest, it’s possible that life may have once evolved there long ago—and there may even be organic compounds or other remnants of life waiting to be found by the rover in the future.
September 5, 2013
Last month, James Hammond, a volcanologist at Imperial College London, traveled with Clive Oppenheimer and Kayla Iacovino of the University of Cambridge to install six seismometers on Mount Paektu—an active volcano on the border of China and North Korea that is famous for, among other things, being the alleged birthplace of Kim Jong-Il. Hammond has previously placed seismometers in locales as far-flung as Eritrea, Ethiopia and the Seychelles, but installing them in North Korea was a new challenge.
“When I first told people about the project, there was a bit of disbelief. People thinking, ‘you must be mad,’” Hammond says. “At times, I even thought myself that it wouldn’t work out.”
His team isn’t the only group of Western scientists to work in North Korea in recent years, but they are one of just a handful, and the first to install scientific equipment in the country’s natural environment. Their project began, Hammond explains, as a result of interest from North Korean researchers.
“The volcano has a pretty dramatic history,” he says. “About 1000 years ago, there was a huge eruption—it was among the top ten eruptions in recorded history, and it dropped ash more than 1000 miles away—so it’s got the potential to be very explosive.” Between 2002 and 2006, researchers on the volcano’s Chinese side observed increased seismic activity, along with slight swelling—both factors that could be harbingers of an upcoming explosion.
This increased unrest in the volcano led researchers in the Korean Earthquake Bureau to seek outside expertise in studying Paektu (sometimes spelled Baekdu, and called Changbai in China). They approached the Beijing-based Environmental Education Media Project (EEMP), which contacted Richard Stone, who was then the Asia editor of Science and had previously traveled in North Korea to document the country’s fight against tuberculosis. He, in turn, recruited Hammond and Oppenheimer to install equipment to help characterize the volcano’s activity and perhaps enable scientists to someday predict when it’ll erupt next.
After a weeklong information-gathering trip in 2011, they set about planning a research project, which Stone documents in a news article published today in Science. “No one had done much research into what drives the volcano, from a scientific point of view,” Hammond says.
That’s not a huge surprise, given both the international sanctions that prevent most people from visiting North Korea—let alone bring in scientific equipment—and the country’s ultra-secretive regime. Over the next few years, the group worked to cut through the bureaucratic red tape that prohibits bringing and using virtually all outside technology (including flash memory drives) into the country in preparation for their trip.
Then, last month, the trio returned and spent 16 days in the country. One of their primary goals was installing six seismometers in specially-built concrete huts on the mountain. The instruments—which precisely measure seismic movement in the ground—will eventually help Hammond and other scientists better understand the internal dynamics of Paektu.
“Essentially, whenever earthquakes occur anywhere in the world, we’ll record them in North Korea, and use the way that energy interacts with the ground underneath to build an image of what the inside of the volcano looks like,” Hammond says. “If we can understand that, that can guide us in thinking about the potential for future eruptions.”
Additionally, Oppenheimer and Iacovino gathered geologic samples, mostly pumice, from a variety of sites around the mountain. “From collecting the rocks, you can get an idea of what state the volcano was in just before it erupted,” says Hammond.
They stored some of their equipment in the houses of local villagers, most of whom had never seen a Westerner before. “They were incredibly nice, really friendly,” Hammond says. “We even got to eat lunch with them on occasion. Everyone seemed happy to be involved, and recognized this was something important that needed to be done.”
Similar to how the few Westerners who visit North Korea as tourists are required to take part in a state-organized sightseeing tour, Hammond’s team was taken to see a series of officially-sanctioned sites. “We went to Kim Jong-Il’s birthplace, which is actually on the flanks of the volcano,” Hammond says. “And we saw Arirang, which is really special—it’s like 100,000 people doing gymnastics, and at the back they have 10,000 people holding cards that they flip around to make pictures.” Some of the cards, in fact, showed Paektu, which is traditionally considered an ancestral origin of Korean culture, in addition to Kim Jong-Il’s birthplace.
Hammond counts the trip as a big success. Logistical hurdles obviously remain—for the foreseeable future, for example, the seismometers’ data will be downloaded and sent out every few months by the Korean Earthquake Bureau, instead of transmitted in real time. Still, he found that working with North Korean researchers was not much different from working with scientists anywhere.
“Communication can be hard, but I found that once we got into the science, there was something of a common language for all of us,” he says. “They want to understand that volcano—that’s what drives them, and that’s what drives us as well.”
August 28, 2013
If the phenomena of Star Trek, Area 51, Ancient Aliens, or War of the Worlds can be taken as anthropological clues, humanity is consumed with curiosity about the possibility of life beyond Earth. Do any of the 4,437 newly discovered extrasolar planets contain traces of life? What would these life forms look like? How would they function? If they came to Earth, would we share ET-esque embraces or would the visit be more a Battle Los Angeles style throw down?
Life outside of Earth has spawned endless interest, but less public interest seems to be given to how life on Earth began 3 to 4 billion years ago. But the two topics, it turns out, might be more connected than one would believe–in fact, it’s possible that life on Earth really began outside of Earth, on Mars.
At this year’s Goldschmidt conference in Florence, Steve Benner, a molecular biophysicist and biochemist at the Foundation for Applied Molecular Evolution will present this idea to an audience of geologists. He’s well aware that half the room will be adamantly against his idea. “People will probably throw things,” he laughs, hinting at a consciousness of how out-of-this-world his ideas sound. But there’s scientific basis for his assertion (PDF), a logical reason for why life maybe truly did begin on Mars.
Science holds a number of paradoxes: If there are an infinite number of stars in the sky, why is the night sky dark? How can light act as both a particle and a wave? If the French eat so much cheese and butter, why is the incidence of coronary disease in their country so low? The origins of life are no different; they, too, are dictated by two paradoxes: the tar paradox, and the water paradox. Both, according to Benner, make it difficult to explain the creation of life on Earth. But both, he also notes, can be solved by placing the creation of life on Mars.
The first, the tar paradox, is simple enough to understand. “If you put energy into organic material it turns to asphalt, not to life,” Benner explains. Without access to Darwinian evolution–that is, without organic molecules having the opportunity to reproduce and create offspring who themselves, mutations and all, are reproducible–organic matter that is bathed in energy (from sunlight or from geothermal heat) will turn into tar. Early Earth was full of organic materials–chains of carbon, hydrogen and nitrogen that are believed to be the building blocks of life. Given the tar paradox, these organic materials should have devolved into asphalt. “The question is, how is it possible that the organic materials on early Earth managed to leap from their asphaltic fate to something that had access to Darwinian evolution? Because once that happens–presumably–you’re off to the races, and then you can manage whatever environment you want,” Benner explains.
The second paradox is the so-called water paradox. The water paradox states that even though life needs water, if organic material could escape its asphaltic fate and move toward Darwinian evolution, you can’t assemble the necessary building blocks in a flood of water. The building blocks of life start with genetic polymers–the well-known player DNA and its less-famous but still very smart friend RNA. Experts agree that RNA was likely the first genetic polymer, partly because in the modern world, RNA plays such an important role in the manufacturing other organic compounds. “RNA is the key to the ribosome, which is what makes proteins. There’s almost no question that RNA, which is a molecule involved in catalysis, arose before proteins arose,” Benner explains. The difficulty is that for RNA to assemble into long strands–which is needed for genetics–you can’t have the assembly taking place in water. “Most people think that water is essential for life. Very few people understand how corrosive water is,” Benner says. For RNA, water is extremely corrosive–bonds cannot be made within water, preventing long-strands from forming.
However, Benner says that these paradoxes can be resolved with the help of two very important groups of minerals
. The first are borate minerals. Borate minerals–which contain the element boron–prevent life’s building blocks from devolving into tar if incorporated into organic compounds. Boron, as an element, is seeking electrons to make itself stable. It finds these in oxygen, and together the oxygen and boron form the mineral borate. But if the oxygen boron finds is already bonded to carbohydrates, the carbohydrates linked with boron form a complex organic molecule dotted with borate that’s less resistant to decomposition.
The second group of minerals that come into play
involve those that contain molybdate, a compound that consists of molybdenum and oxygen. Molybdenum, more famous for its conspiratorial relation to the Douglas Adams classic A Hitchhiker’s Guide to the Galaxy than for its other properties, is crucial, because it takes the carbohydrates that borate stabilized, bonds to them and catalyzes a reaction which rearranges them into ribose: the R in RNA.
Which brings us–however circuitously–back to Mars. Both borate and molybdate are scarce and would have been especially scarce on early Earth. The molybdenum in molybdate is
highly oxidized, meaning that it needs electrons from oxygen or other readily available negatively charged ions to achieve stability. But early Earth was too oxygen-scarce to have readily created molybdate. Plus, returning to the water paradox, early Earth was quite literally a water world–with land making up only two to three percent of its surface. Borates are soluble in water–if early Earth was a flooded planet, as scientists believe, it would have been difficult for an already scarce element now diluted in a huge ocean to find ephemeral organic molecules to bond with. Moreover, Earth’s status as a water-logged planet makes it difficult for RNA to form, because that process can’t easily happen in water on its own.
These concepts become less of an issue on Mars, however. Though water was certainly present on Mars 3 to 4 billion years ago, it was never as abundant as it was on Earth, creating the possibility that Martian deserts–locations where borate and molybdate could concentrate–could have fostered the formation of long strands of RNA. Moreover, 4 billion years ago, Mars’ atmosphere contained much more oxygen than Earth’s. Further, recent analysis of a Martian meteorite confirms that boron was once present on Mars.
And, Benner believes, molybdate was there too. “It’s only when molybdenum becomes highly oxidized that it is able to influence how early life formed,”Benner explains. “Molybdate couldn’t have been available on Earth at the time life first began, because three billion years ago the surface of the Earth had very little oxygen, but Mars did.”
Benner believes that these factors imply that life originated on Mars, our closest neighbor in space equipped with all the right ingredients. But life wasn’t sustained there. “Of course Mars dried out. The process of drying was very important for life originating, but not sustaining,” Benner explains. Instead, a meteor would have to have hit Mars, projecting materials into space–and eventually those materials, including some building blocks of life, might have made it to Earth.
Would the sudden change in environment have been too harsh for the fledgling building blocks to survive
? Benner doesn’t think so. “Let’s say life starts on Mars, and becomes very happy in the Martian environment,” Benner explains. “A meteor comes to hit Mars, and the impact ejects rocks on which your predecessor is sitting. Then you land on Earth, and you discover that there is lots of water that you were treating as a scarce element. Will it find the environment adequate? It certainly appreciated the existence of enough water that it didn’t have to worry.”
So, sorry Lil Wayne, looks like it might be time to relinquish your claim to the fourth rock from the Sun. As Brenner notes, “The evidence seems to be building that we are actually all Martians.”
July 24, 2013
When plans were scrapped in 2009 for the Yucca Mountain nuclear waste repository, some worried that expansion of American nuclear power might dissolve along with it. Without a safe, permanent site to store the country’s 70,000 metric tons of nuclear waste–currently stored in temporary pools and dry casks at 75 sites around the country–it seemed that a robust expansion of nuclear power might have to be put on the back burner.
But a viable option might be on the horizon; in an article (pdf) published this week in Eos, the newspaper of the American Geophysical Union (AGU), U.S. Geological Survey hydrologist Christopher Neuzil suggests that shale–a
mineral rock found in abundance in the United States–could be the key to a future of safe disposal for nuclear waste.
Shale and other argillaceous formations (any clay-rich media such as mudrocks) possess certain unique qualities which would make them prime candidates for the disposal of nuclear waste, Neuzil argues. Argillaceous formations have extremely low permeability, meaning that risk for toxic runoff from waste storage would be greatly reduced. Nuclear runoff is one of the greatest concerns for waste storage, which comes from waste dissolving in groundwater flowing through the storage area. Because water flows through shale at an extremely slow rate, Neuzil says that the material would act as a distinct barrier between nuclear waste and potential runoff. In fact, shale can act like a sponge, absorbing water without releasing any; this would allow nuclear waste to be stored safely,
keeping the waste materials inside the formations.
Moreover, Neuzil cites the natural abundance of shale in the United States as a clear advantage. “The United States is in an enviable position with respect to the scale and sheer diversity in age, history, composition, and thickness of argillaceous formations within its borders,” Neuzil writes. “Geologically and geographically, potential choices for a repository are many.” Moreover, the locations of these formations constitute another benefit to waste storage; because the formations are often found in relatively old and geological stable areas, the risk for tectonic disturbance would be greatly reduced.
The low permeability of shale is something that Americans are starting to be familiar with–its what allows shale gas and oil, which forms when organic components within the rocks break down, to collect without escaping. In fact, fracking to extract shale gas is conducted to overcome shale’s impermeable nature. But rather than seeking to extract what may be inside the shale to produce energy, scientists like Neuzil see shale as a medium to house the byproducts of energy that has already been produced. And with nuclear energy responsible for nearly 20 percent of the nation’s energy production, our need to permanently dispose spent nuclear fuel grows every year.
The United States has only recently begun researching the potential for shale disposal, but Neuzil cites multiple studies which have been conducted–or are underway–in Europe and beyond, from the United Kingdom to Japan. France, Belgium and Switzerland have moved beyond the research process, and are currently devising plans to implement shale-storage of their nuclear waste (pdf). Though there is concern that emplacement would potentially disrupt the integrity of shale as a barrier to waste,
studies in Europe suggest that the formations, even with cavities made for waste storage, maintain their ability to keep groundwater from carrying contaminates any measurable distance.
Shale is not without its caveats, however. Neuzil notes that the research surrounding shale’s potential for nuclear storage must be mostly extrapolated from other minerals, as shale’s low-rate of water flow also makes studying the phenomenon difficult. Instead of studying shale’s permeability in the long term, scientists use rocks with faster flow-rates, which are quicker and easier to study in the short term, and apply the properties to shale. This could pose threats to the long-term success of shale storage, as no data exists on its true ability to weather long-term storage situations.
So how do you actually get spent nuclear fuel into these clayey rocks? Neuzil suggests that the waste would be placed mostly in solid form. “Some waste may be vitrified, or mixed with molten glass that then solidifies. This may make it more difficult for the waste to contaminate any groundwater that contacts it,” he explained in an interview, adding that any waste would also be placed in canisters (stainless steel or copper) to further impede contamination of the ambient environment.
In April of this year, the Department of Energy announced plans to launch a new research and development project led by the Electric Power Research Institute (EPRI), a 15.8 million dollar investment that will center around design and implementation of dry cask storage for nuclear waste. The initative mentions nothing about expanding research to other options–geological or otherwise–though a spokesperson for the Department of Energy notes that they are currently “analyzing the capabilities of various geologic media, including clay, salt, crystalline rock and shale, for repository disposal in the United States,” as well as taking advantage of existing research conducted by other countries.