For advocates of space travel, the news is grim, and we’re not talking about the crash of a six-ton satellite last week, either. In July, the last U.S. space shuttle was parked, as planned. Over 30 years, the shuttles helped build the International Space, but two explosions killed 14 astronauts, and each flight cost nearly half a billion dollars.

On August 24, a clogged pipe caused the crash of a Russian Soyuz rocket. Soyuz is a reliable space-truck whose ancestor launched Sputnik, the first artificial satellite, in 1957.

With the shuttles in the old-age home, any delay of a Soyuz launch to resupply the space station, planned for Nov. 14, could force the station’s evacuation.

Abandoning the space station after a decade of continuous occupation might have limited scientific impact, as the station is not proving to be a scientific bonanza as promised. (However, on Sept. 21, NASA reported that a Japanese astronaut did perform “bubbling experiments” on green tea before staging a “traditional Japanese tea ceremony.”)

The growing problem of getting into space got more attention on Aug. 24, when a sub-orbital space taxi built by Blue Origin, a company funded by Amazon founder Jeff Bezos, crashed in West Texas, setting back the nascent space-tourism industry.

People have been going into space for 40 years, but the process is neither cheap nor routine. For comparison, 40 years after the first automobiles, millions of cars were changing the U.S. economy and landscape. And 40 years after Kitty Hawk (1903), airplanes had circled the globe and become a dominant force in World War II.

So, 40 years after Yuri Gargarin became the first space-farer, why is it so hard to get people into space?

It’s the gravity, stupid!

The first clue to the difficulty of reaching orbit is evident in the controlled explosion needed to launch anything: reaching orbit requires a speed of almost 18,000 miles per hour and overcoming gravity.

And gravity is a stern customer.

Although gravity is fixed, a changing political backdrop has deprived the space program of its historic justification, says Howard McCurdy, a professor of public administration and policy at American University, and student of the space program. “The key problem, as a political scientist, was the end of the Cold War. Now the rationale for a lot of human space program is jobs, but in the absence of Cold War competition, we get these anomalies,” like thumbing a ride to space from your former enemy.

Faced with the prospect of being stuck on Earth, on Sept. 14, NASA administrator Charles Bolden announced the Space Launch System (SLS), a heavy-lift rocket and space capsule designed to reach earth orbit and beyond. “American leadership in space will continue for at least next half century,” Bolden said. “We have laid the foundation for success.”

Better than nothing?

The reaction to SLS was a bit ho-hum. The proposal “has been controversial because some say it’s just the same old technology, a combination of Apollo, Saturn V, and the shuttle, and we really should be advancing the technology, doing something new that will get us to deep space more quickly,” says astrophysicist Jack Burns, who has served on the NASA Advisory Council science committee, and is vice-president emeritus for academic affairs and research at the University of Colorado System.

But what else is there? Burns asks. “I look at SLS as a practical vehicle that will get a lot of mass into orbit, and then to the moon, the asteroids. Having a heavy lift vehicle, for the first time since the mid ’70s, when we did away with Saturn V, should be an important part of U.S. space architecture.”

The shuttle, whose demise has forced the current concern over space launching, was hatched in 1972, by Pres. Richard Nixon, who proposed a reusable, flying bus to reach low orbit and “take the astronomical costs out of astronautics.”

Getting to orbit didn’t turn out to be cheap: NASA chalks up the average price tag on 135 shuttle launches at $450 million.

Consternation over Constellation

In 2005, faced with mission failures and an aging shuttle fleet, Pres. George W Bush called for the shuttle program to end after the space station was constructed. As a replacement, Bush proposed Constellation, a new rocket, and Ares, a new spaceship, which would visit the moon and then Mars.

However much the Mars mission was beloved by space-travel enthusiasts, it carries certain health hazards…

Cost estimates for Constellation and Ares rose faster than a rocket and by 2010, the projects had black-holed $9 billion, and the guesstimated price of launching a single Ares-1 had reached $1 billion. So Pres. Obama trash-binned the twin projects and directed NASA to come up with something cheaper and faster – which turned out to be the poetically-branded “Space Launch System.”

The proposal has, as we’ve said, met grudging acceptance at best. “This is a turning point for all kinds of reasons,” says Michael G. Smith, a space historian at Purdue University. “The shuttle program is finished after 30 years — it was too expensive, too old — and the Bush program to take us to the moon is finished.”

Although NASA has another job — the SLS — the manned space program needs goals with more focus, Smith says. Because Obama has failed to set a clear challenge before NASA, “they have nothing to prove, no short-term mission.”

In a sense, Smith adds, the Obama plan conforms to American desires. “There’s a paradox. A Gallup poll says the American public wants a space program, and is proud of it, but does not want to pay for it, and that’s the Obama Administration approach: ‘We want something, we have announced something, without a clear-cut commitment to what it is.’”

Take the money and … design?

In an era that is short of cash and jobs, however, NASA has an immense constituency in its legion of employees, contractors and their employees, Smith says. “Lawmakers with NASA investment in their districts are challenging the administration’s lack of clarity.”

But viewing a space program as a jobs program is unlikely to maximize either cost savings or scientific breakthroughs. “NASA has half-lost the ability to innovate,” says McCurdy. “People are hunkering down like turtles, protecting what they have, playing defense to hang onto the field stations [such as Marshall Space Flight Center in Alabama], and Congress is pushing them in ways that are inefficient for cost reduction. Most members want to know if contracts are still going to their districts.”

Space is inherently expensive, and McCurdy questions whether the current NASA budget will accomplish much space travel, or mainly rocket design and construction. “A big issue for NASA is whether the budget for exploration is going to be sufficient to actually develop, build and test the rocketry,” he says. “It looks like it will be sufficient to provide aerospace jobs, but they need a little bit more money to bend metal.”

Confronting costs

It’s odd, McCurdy says, that developing a new rocket and space vehicle are expected to cost $100 billion, considering that Saturn V, which launched Skylab and the moon shots, cost about $10 billion in 1960 dollars. “Multiply that by five to get today’s price — $50 billion — and that included the production line, a test vehicle and the actual rocket.”

Much engineering has been done for Constellation and previous rockets, and McCurdy, who acknowledges that the engineering and manufacturing expertise and the Saturn assembly line have long disappeared, wonders why NASA cannot produce a heavy-lift rocket for $50-billion.

Cutting the budget to the bone can be penny wise and pound foolish, McCurdy adds. “Once they got the assembly line going for Saturn V, it was very efficient, but if they build only one rocket every two years, it becomes more of a craft rocket.”

What are the other options for launching people into space?

Government rocket, private rocket

International rockets such as Ariane have gotten into the satellite-launch business, but most of them are not powerful enough to take people into orbit, or to leave earth orbit and reach the moon.

China, with one satellite orbiting the moon, and an imminent launch of an 8.5 ton component for its first space station, definitely has the lift capacity, but we’ve not heard about any discussions about launching U.S. space equipment.

Government is not the only game in town, however, and many hope that the genius of private enterprise will fill the gap, even if some of the efforts are watered with buckets of federal funds. If you place a challenge before rocket manufacturers, “both the startups and old horses, somebody may come up with a breakthrough,” says McCurdy. Even so, he adds, NASA must still “pick a winner before knowing whether it is a working design, and they are no better at that than I am at picking stocks.”

So how is the private sector faring in the human space travel biz?

the private role

Corporations are contending for two roles in space. Many are interested in space tourism, a business that began in 2001 with a seven-day visit to the International Space Station but today is focused on sub-orbital flights – spending a few minutes in micro-gravity beyond the edge of the atmosphere:

Photo: Jim Campbell/Aero-News Network

SpaceShipOne, built by Scaled Composites, slung beneath White Knight, the mother ship that lifts it toward the edge of space.

Blue Origin, a secretive operation funded by Jeff Bezos, the Amazon.com billionaire, is working on “New Shepard,” a sub-orbital vehicle. According to the website, “We’re working, patiently and step-by-step, to lower the cost of spaceflight so that many people can afford to go and so that we humans can better continue exploring the solar system. Accomplishing this mission will take a long time, and … we do not kid ourselves into thinking this will get easier as we go along.” Blue Origin has a NASA contract to develop a taxi for hauling astronauts to orbit, but recently lost a spaceship at 45,000 feet.

Scaled Composites, an advanced aircraft maker, won the $10-million X-prize in 2004 for attaining 328,000 feet twice within 10 days. The firm is working with Virgin Galactic to enhance its a sub-orbital spaceship-mother-ship combination. Virgin says 430 private-nauts are already put down a deposit for flights that will cost $200,000.

Xcor Aerospace is also selling seats on an unfinished spaceship, for a suborbital flight priced at $95,000, starting with a spare-change deposit of $20,000. Buy now, and your seat-mate could be a Victoria’s Secret model… Honest!

Let’s really go to space!

Above the sub-orbital realm, however, comes the real high-technology interest: resupplying the space station, or reaching the moon or an asteroid. In this realm, one company has grabbed most of the headlines: SpaceX, founded by PayPal founder Elon Musk.

SpaceX is developing two types of “Falcon” rockets, and has a $1.6 billion NASA contract to launch 12 loads of cargo to the space station (the first flight is scheduled for Nov. 30), in NASA’s Commercial Orbital Transportation Services program. (Orbital Science Corp. is the other contractor in the program.)

In December, 2010, SpaceX became the first private company to launch and recover a spaceship. “The technology has advanced,” says Burns, “but so far SpaceX only has a couple of launches of the Falcon 9. It’s a long way from that all the way to orbit, with real live astronauts. It’s a risky venture.”

SpaceX says it emphasizes reliability, and the business end of Falcon 9 houses nine individual rocket engines. The rocket is supposed to reach space even if one engine goes kaplooey.

A human role remains

When President Ronald Reagan proposed and promoted what is now called the International Space Station, a howl went up among scientists who called it a diversion of resources from the more productive unmanned spacecraft. Carting people around raises the price and the stakes at every stage of design, production and operation, and these scientists accurately forecast a fruitful program of robotic exploration — everything from the Hubble Space Telescope, to the Opportunity and Sojourner rovers on Mars to the Galileo spaceship that explored Jupiter.

Those robots were awesome and inspiring, says Burns. “Opportunity is U.S. technology, it’s something we all should be proud of it, it has well exceeded its lifetime, the engineers were very clever in the design and operation. That good old-fashioned American ingenuity ought to get kids excited about going into science, engineering, math, whether that gets directed to space or something else.”

The manned vs. robot argument had merit in its time, given that the space station alone has cost NASA north of $50 billion (with other countries contributing about the same amount), and NASA never has enough money for all the scientists who write grants, which leads some critics to question whether the money is well spent, or would have been more productive if spent on funding conventional science.

But the manned vs. robot dichotomy may be fading, says Steven Collicott, a professor of aeronautics and astronautics at Purdue University, who placed an experiment about the fluid flow in micro-gravity on the space station. “There is a great benefit to doing both. The astronauts who have operated space station experiments I have been involved in have been incredibly creative thinkers, problem solvers.”

The flow experiment cannot be performed on Earth, Collicott says. “We do everything we can to test on earth, or on short-duration, low-gravity [aircraft] flights, but there are times when … the camera position needs to be changed, or a liquid gets trapped. An astronaut can unbolt and shake the experiment … or act on their observations to explore a new phenomenon immediately, without reprogramming, relaunching or rebuilding, which involves years and millions of dollars.”

Human hands, eyes and brains are irreplaceable, Collicott says. “If people were not needed for research of this type, why would we be spending money to send people to Antarctica each year?”

human vs. robot — the dichotomy wanes

“I never felt comfortable with the manned versus unmanned argument,” says Purdue’s Smith. “We have always pursued both [approaches]. Satellite, probes and telescopes… There is no ICBM [inter-continental ballistic missile] system without satellites, there is no exploration of the moon or Mars without the [robotic] probes we have sent there.”

More on the manned vs. robot issue…

Yet despite the phenomenal allure of space-telescope photos, manned exploration plays a critical motivational role, Smith adds. “Without an orbital station, and the public interest and international cooperation that revolve around it, NASA can’t do anything. Satellites and probes just don’t drive that public interest.”

What Smith calls “fierce debates” between astronomers, who favor robotic exploration, and engineers who favor manned exploration are “not about policy or philosophy, they center on funding; those seem to me very parochial questions.”

Burns offers one suggestion for merging people and robots: sending astronauts to a low-gravity point above the far side of the moon (which never faces Earth), where they could control a moon rover. “Astronauts who are familiar with geological exploration could operate the rover in real time, there’s much less delay [in the radio signals]. They could visit the oldest [known] impact basin in the solar system, and it would not require a human lander, would be cheap, and would give you the kind of experience that is going to be needed” for further exploration of the solar system.

The quest to populate the solar system would entail a search for signs of life – and for water and useful minerals, Burns says. “This is going to require knowledge of geology, chemistry, astronomy and mechanical engineering; it will be very different than the first few flights to the moon that were just trying to get there. I argue that the difference between manned and unmanned travel is going to start to fade.”

Historic moment

Tele-operation, as remote-control is currently called, is being used every day by earthbound “pilots” in Nevada to fly drones in the Middle East, highlighting the firm link between space engineering and the military.

Rockets and satellites have military roots, and the space race was an early and intense focus of Cold-War competition, as the United States and Soviet Union both relied on German rocketeers who had helped the Third Reich try to conquer Europe. Now the United States and Russia, World-War II allies, then Cold-War enemies, have become allies once again, at least in terms of space cooperation.

Dating back to the late 1950s, Smith says, “Space policy has always been as much about perception as reality. It goes all the way back to the first ballistic missiles, the space race, the missile gap.”

John F. Kennedy warned about a “missile gap” while running for president, and even though it proved illusory, the fear of Soviet supremacy — Sputnik was in orbit while American rockets were exploding in front of TV cameras — supported the development of missiles that could be used for global nuclear war or putting men on the moon.

The result was lavish budgets for rockets and space.

But the easy goals have been reached, and visiting the moon is so last-century. Visiting an asteroid will answer important scientific questions, but will never have the sex appeal of visiting the man on the moon. As Smith says, today, “We are in another gap; an ambition gap.”

David J. Tenenbaum

Wondrous weevils sport super screw!

In animal appendages, some joints resemble hinges. Others, like your hip, are unmistakably akin to the ball-and-socket joint, another mechanical mainstay.

Now, scientists have found a biological screw in a type of beetle called a weevil. Obliquely described as having “rotational movement combined with a single-axis translation,” the new screw-and-nut assembly was first seen in a weevil from New Guinea, says entomologist Alexander Riedel.

The discovery of the first biological screw-and-nut assembly emerged from an exploration of the weevil’s characteristic defense mechanism, says Riedel, an entomologist and curator who specializes in weevil classification at the State Museum of Natural History in Karlsruhe, Germany.

Two things weevils have in common are small size – the Trigonopterus oblongus under study was about 4 millimeters long – and legs that fold under the body. “We wanted to look at their particular defense mechanism,” says Riedel, “to know how it works.”

Using a microscopic counterpart to CT scanning, German researchers snapped electron micrographs of the weevil’s trochanter (“screw”) and (ROLLOVER) coxa (“nut”).”

Image © Science/AAAS

It’s all in the scan, man!

Given the small size, the scientists relied on a kind of micro CT scan driven by X-rays from a synchrotron, “We realized there is a very nice screw joint,” Riedel says, “We’ve had this information for some time, but while talking with a herpetologist colleague, we realized there is no other case in the whole animal kingdom, in all of biology, with a similar screw joint.”

The nut-and-screw are located at one of three major joints in the beetle’s leg; when the leg is retracted, the screw tightens in the nut, which remains stationary, Riedel says. Overall, the screw and nut would be able to turn 345 ° although the leg itself does not move that much.

A (good) turn of the screw!

“The weevils, or snout beetles, have been known from ancient times,” says Riedel. “There are grain weevils and lots of other species, including the boll weevil [a cotton pest]. Many other species are not pests … and so are of no particular interest to humans, which is why nobody knows much about them.”

Why does every weevil species that that Riedel examined have such a mechanism? Weevils, which spend a lot of time climbing on vegetation, apparently evolved from beetles that usually walk on a flat surface or underneath bark, Riedel says. “If a weevil is sitting on the edge of a leaf and wants to walk on a small twig, it’s essential that it can grip under its body, and this motion goes very nicely with this screw joint. A ground [walking] beetle would have great difficulty walking in similar conditions.”

The screw joint now joins the hinge, ball-and-socket and saddle joint as fundamental technologies invented by evolution, Riedel says. Historians of technology have long wondered about the origin of the incredibly useful screw, and it turns out that screws and nuts were in their flour bins all along – but only visible to those who happened to have a handy synchrotron!

– David J. Tenenbaum

Hunger season approaching?

In some places, the harvest is preceded by “hunger season,” when stored crops are exhausted but the new crop is not ready. For many reasons, we’re wondering if the Earth is entering a long hunger season:

Food prices reached records in February, which may even have helped spark the political unrest that swept the Middle East. As Lester Brown of the Earth Policy Institute notes, a 10 percent rise in the price of wheat barely budges the price of bread in developed countries, but directly boosts the price of chapattis in India.

The population is expected to reach about 9 billion by 2050, and 3 billion people with rising incomes have a growing appetite for grain-intensive animal protein.

The World Food Program estimates that one person in seven goes to bed hungry. One reason is poverty: In this world, only the poor are hungry. But other reasons are related to supply and demand:

The end of civilization?

Depleted soil is a legacy of many failed civilizations, wrote soil scientist David Montgomery1 of the University of Washington. “In recent decades, archaeological studies confirmed pronounced episodes of soil erosion associated with the rise and subsequent decline of civilizations in the Middle East, Greece, Rome, and Mesoamerica, as well as other regions around the globe.”

Indeed, Montgomery writes, “a limiting lifespan of an agricultural civilization can be estimated by the time needed for conventional agriculture to erode through the native stock of topsoil,” which “predicts reasonably well the historical pattern of a 500- to several-thousand-year lifespan for major civilizations around the world.” These calculations, he says, support the argument “that it was not the axe that cleared forests but the plow that followed that undermined many ancient societies.”

Soil health is often gauged by the percentage of organic matter — the decomposing plant material that feeds microbes and soil animals, and enables soil to hold water and nutrients, says Jane Johnson, a soil scientist with the U.S. Department of Agriculture in Minnesota. “Most of the characteristics that we associate with high quality soil are directly or indirectly linked to soil organic matter.”

Therefore, the emphasis on protecting and improving soil so it can feed an ever-growing population often comes down to the level of organic matter. In the United States, much of the cropland has already lost 30 to 50 percent of its organic matter since Europeans started farming a couple of centuries ago, says Rattan Lal, a professor of environment and natural resources at Ohio State University.

Most productive soil in Africa and Asia has lost 70 percent to 80 percent of its organic matter, says Lal, an outspoken defender of the soil, and long ago crossed the line toward ruination. “There is a threshold — about 1.2 percent to 2 percent of carbon [the usual measure of organic matter] — to maintain soil health, water retention and other soil services.”

Many soils in Africa, India and China have only one-tenth that much carbon, Lal says, and that leads to a truckload of trouble. “When you add fertilizer, it washes into the groundwater because the organic matter is not there, and the same goes for pesticides and herbicides. These chemicals wash into rivers or the groundwater, or enter the atmosphere, where they cause human health and environmental problems,” without conferring much benefit to the crop.

Lal says a train in his native Punjab, India is dubbed the “Cancer Express” because it travels through a region where “many people are prone to cancer because of pollution of the drinking water. The soil does not have the capacity to hold water and pollutants. That is what the biological health of soil does; you get microbial decomposition, absorption of organic matter and retention of water. If crop residues are taken away, if dung is taken away for cooking, the soil has nothing left to provide the services. It essentially becomes a sand culture.”

Good soil, great benefits…

About the only bright spot in the grim picture of soil destruction is this: many solutions offer synergistic benefits. Leaving a crop residue on the surface cuts wind and water erosion, and raises the level of organic matter. Conservation tillage cuts erosion, reduces the need for irrigation, and stores carbon in the soil. Smart irrigation reduces water use, and the need to plant on steep, erodible slopes.

Soil – some still call it dirt – is not as popular as Facebook or Dancing with the Stars. But it’s a whole lot more important. “Our ability to feed humankind in the future depends on a stable, improved soil resource,” says Jerry Hatfield, director of the Agricultural Research Service lab in Ames, Iowa.

Or, as University of Minnesota soil scientist William Larson once said, “Soil is that thin layer on the planet that stands between us and starvation.”

Enough with the problems. Let’s look at some serious soil solutions.

Washing away

Because water erosion can rapidly flush nutrients, mineral soil and organic matter from hilly land, the battle against water erosion has been a focus of American farmland conservation since the 1930s. One common prescription is contour planting; rows planted across the slope are more resistant to erosion than those running up the slope.

A standard way to protect soil is to leave crop residues in place after harvest, but bioenergy proposals often suggest that these wastes be fermented into cellulosic ethanol. The best solution depends on the situation, Johnson says. “If the land is highly erodible, we should not take residue. But if the landscape has a low erosion risk, then if we can manage it to protect organic matter by leaving enough residue in place, chances are we will have more than enough cover for erosion control. I believe it is possible to take some residue off, but not everywhere.”

The focus in protecting soil has shifted from the mineral component of soil to its organic matter, which is more sensitive, says Johnson. “In most cases, protecting the organic matter will protect against erosion, but if you only manage for erosion control, that may be not enough to retain the organic matter.”

Gone with the wind

The “Black Blizzards” of the 1930s Dust Bowl proved beyond question that wind can transport large amounts of soil to the wrong place. Could we see a rerun of the Dust Bowl? “People say we will never have a Dust Bowl again, because of the conservation practices that we put in,” says Hatfield, but the Dust Bowl also followed years of severe drought, which further stripped farm fields of cover.

Furthermore, says Hatfield, co-editor of a new book on soil management,2 many of the windbreaks planted to slow wind erosion have been removed to allow the use of large farm machinery. “What would happen if, across the Great Plains, we had three or four years with hardly any rainfall? I dare say we would not see the extent of the Dust Bowl, but would our current conservation practices be sufficient? … How much can you expect when the land is naked?”

Confronting drought

The Dust Bowl shocked Americans, but drought is a common problem that has differing consequences. Recent reports show that California’s farm industry did well during the 2007-2009 drought, mainly because large farmers had access to irrigation water. But wheat production in Southwest Kansas is now expected to fall at least 25 percent due to drought. According to Bloomberg News, the state’s wheat crop “has suffered irreversible damage from the country’s driest spring in half a century…”

In places where irrigation is impossible or inadequate, standard soil-conservation techniques, including retaining organic matter in and on the soil, can improve water retention.

ENLARGE

Cities devour farmland

The 80 million people joining the population every year require 3200 square kilometers land for shopping malls, roads, airports and housing. Cruelly, much of that growth occurs in places with productive soil, says Charles Rice, a professor of agronomy at Kansas State University, because big cities typically start out in a region with productive farms. “Chicago is a prime example; the soils in northern Illinois are some of the best in the world, but unfortunately Chicago is growing. I hate to see that valuable productive land paved, built upon. In Asia and Europe, around the world, megacities are consuming land. We need to figure this out, but nobody has.”

Salty soil is worthless soil

A bright idea: reduce tillage, save topsoil

Perhaps the largest success story in protecting soil is the no-till revolution in agriculture. Rather than turning over soil to bury weeds and crop residues, a no-till machine plants directly in the stubble, then controls weeds with herbicide. The process saves diesel fuel and also retains organic matter, says Hatfield, who observes that carbon compounds oxidize rapidly when the soil is disturbed. “We need to protect the soil from within, with more organic matter, and from the external forces, like wind and water.” Sustaining the soil, he says, “Is really about building that organic matter reservoir.”

In 2010, no- or low-till farming occupied at least 20 million hectares each in the United States, Brazil and Argentina, with significant areas in Canada and Australia.

“If you go to South America and talk to producers,” says Hatfield, “they look at conservation practices as the normal accepted practice — if you used a moldboard plow [which turns over the soil and exposes it to erosion] they would probably shoot you! In the last 20 years, they have realized what a precious resources soil is, and to maintain its viability, they have preserved the organic matter.”

But worldwide, no-till occupies only 6 or 7 percent of the 1,500 million hectares under cultivation. “You could call that a success,” says Lal. “But in the places where it is needed most desperately, Africa, Asia, those desperate farmers cannot implement no-till.”

Summing up

Optimism is not a common response to discussions of the world’s degrading soils. Lal says two to three billion hectares already are degraded, but contends that problems related to energy use, global warming and clean water also have strong ties to land degradation.

To take two examples, surface water is easily polluted when it washes off eroded land, and healthy soil stores vast amounts of carbon, slowing global warming. “All these issues are linked with one another, and soil is the common link,” says Lal. “We have the IPCC [Intergovernmental Panel on Climate Change] to address climate change … but soil is addressed by nobody, even though … we cannot address water security, energy, biofuels, global warming, without soil.”

Not to mention the daily problem of putting bread on the table…

But here’s a reason for optimism: The measures that can solve individual problems often can solve multiple problems. Conservation tillage saves water, organic matter, topsoil, even energy. Drip irrigation reduces salinity and saves water and energy. Cover crops raise fertility and reduce erosion.

And, no coincidence, all of these soil-friendly practices also increase yields.

So if you like to eat, the time to think about soil is … now.

On March 11, a catastrophic earthquake — one of the four largest in the past century — struck in the ocean east of Japan, sending a colossal tsunami against the shore. By March 21, the toll of dead and missing, mainly from the tsunami, was estimated at 22,000.

As Japan confronted what Emperor Akihito called the worst crisis since World War II, we began to hear that the six-reactor complex at the Fukushima Daiichi plant, located directly in the tsunami’s path, had lost electrical power. The emergency generators also failed, apparently due to water damage to them or their fuel supply.

As we focus on the nuclear disaster at Fukushima, we emphasize that as of now, the tsunami itself is the far larger human tragedy. But like the tsunami itself, the nuclear disaster may portend further problems in other places, and is likely to affect a trend toward greater use of nuclear power around the world.

Not cool

Immediately, the arrow of trouble aimed at the most ominous type of nuclear accident: loss of cooling. Fission — splitting of radioactive elements that powers nuclear reactors — can stop when reactor operators flip a switch to insert control rods to absorb neutrons. This stops the chain reaction — the divison of uranium atoms that releases neutrons that split other atoms and generate heat — which is the whole point of building nuclear reactors to boil water and drive turbines.

But once the fission reactions cease, decay heat continues to be released from the unstable atoms that remain after fission, and it is this heat that must be removed by a cooling system after shutdown.

Past accidents have shown that decay heat can build up in seconds; and significant damage to the fuel and potentially reactor equipment can occur within minutes. The danger of such a “meltdown” is a major reason why nuclear designers and engineers focus so much effort on cooling the reactor core.

In the beginning, there was Three Mile Island

Japan, target of the only two atomic bombs used in war, is hardly the first nation to confront a “loss of coolant” emergency at a reactor. That happened on March 28, 1979, in the United States, where Pennsylvania’s Three Mile Island (TMI) reactor #2 began a partial melt-down.

Much later, the Nuclear Regulatory Commission concluded that the accident “was caused by a combination of personnel error, design deficiencies, and component failures.” As hundreds of alarms buzzed in the control room, operators, lacking a direct measurement of the water level inside the reactor, made a bad situation worse, the reactor went at least partly dry, and a large percentage of the fuel melted.

It’s safe to say the public reaction verged on panic as a bubble of explosive hydrogen built up inside the plant and evacuations were ordered.

The slow, dangerous removal of fuel revealed massive heating and damage inside the reactor. According to the book, “TMI 25 Years Later”¹: “A large portion of the core melted and flowed into the lower vessel. Most of the core experienced temperatures of at least 1727° C, with certain parts reaching 2527°C.”

At these temperatures, the essential containment vessel can weaken and fail.

TMI, the above book concluded, neared a complete a meltdown. “No one can say for sure, but some experts say that had the accident continued for another 20 to 45 minutes, the [reactor] vessel would have heated up and the metal would have lost its strength, leading to a rupture,” preventing further cooling and allowing superheated fuel to melt through the reactor vessel and enter – and likely exit — the reactor building.

From there, it’s impossible to speculate how widely the radiation would have spread, the authors wrote, but this is what is called the China Syndrome — a runaway load of reactor fuel melting its way down into the earth. Oddly, “China Syndrome” – the movie — was released 12 days before the TMI meltdown.

TMI #2 has since undergone a major cleanup. Intact and damaged fuel has been moved to storage at Idaho National Engineering Laboratory. Reactor #1 is operating normally, and final removal of the destroyed #2 awaits the decommissioning of its companion.

According to the Nuclear Regulatory Commission: “Estimates are that the average dose to about 2 million people in the area was only about 1 millirem. To put this into context, exposure from a chest X-ray is about 6 millirem.”

Nevertheless, the alarm over TMI sent the U.S. nuclear industry into a tailspin.

 

The meltdown of TMI was the death knell for growth in American nuclear industry — the spate of plants licensed during the 1980s had all been planned or under construction by 1979. Rollover to see a comparison of present dependence on nuclear energy.

Graph 1: U.S. Nuclear Regulatory Commission. Graph 2: International Atomic Energy Association

Chernobyl – the unmitigated disaster

The Lord Voldemort of nuclear accidents started on April 26, 1986, when Chernobyl reactor #4 exploded, burned and melted down in a spectacular fire that spewed an estimated 50 tons of radioactive fuel over a swath of Eastern Europe. Unlike TMI (and the imperiled Japanese reactors) Chernobyl had no vessel to contain its fuel, and a giant fire – consuming the estimated 800 tons of graphite used to slow neutrons in the reactor — burned for more than a week as brave crews tried to damp it with sand, boron and lead.

Chernobyl was located in a part of the Soviet Union that is now in Ukraine.

The meltdown produced some of the worst radiation injuries in history, and hundreds of thousands were force-evacuated from an “exclusion zone” — roughly 30 kilometers in radius — around the smoking, radioactive hulk of #4.

Within months, the cooling reactor was hastily wrapped in a giant concrete “sarcophagus” (stone coffin) to contain further radiation. But the sarcophagus is leaking, says Leon West, a professor of mechanical engineering at the University of Arkansas, who has 40 years of experience in nuclear physics, radiation protection and nuclear engineering. “Chernobyl is still open and is still a threat to the local environment.”
“Construction has already begun on the New Safe Confinement,” says photographer Michael Foster Rothbart, who lived 12 miles from the exclusion zone between 2007 and 2009, “and although it keeps falling behind schedule, target finish date is 2013.”

Japan: Facing Three Mile Island or Chernobyl?

By March 21, 10 days after the tsunami, the owners of the Fukushima power plant reported that it had reconnected electric power to all six reactors. The disaster seems headed toward resolution, says Jeff Geuther, who manages a research reactor at Kansas State University. “My understanding is that the fuel [in the three recently operating reactors and the three spent-fuel pools at other reactors] is all under water. The radiation dose has been falling at the plant, an indication that water level has increased in the spent fuel pools.”

Although it’s not clear how much fuel has melted, Geuther says, “It’s fairly clear that the cladding [a thin sheathing on the fuel rods], at a minimum, had some damage. Iodine and cesium have been detected offsite; these are fission products that would be typically be trapped inside the cladding.”

By March 23, the utility reported that the lights were on in the control room of reactor #3, but work had not yet begun on monitoring equipment and reactor cooling pumps in the three reactors that were operating before the quake. By March 24, smoke was rising from several reactors, three plant employees were being treated for radiation exposure, and the zone of concern about radiation in drinking water had been expanded. The local populace remains under evacuation.

Near-term progress in stabilizing the Fukushima plant will be measured by

A near miss?

Two positive factors helped what looks like a near-miss at Fukushima. First, those reactors (unlike Chernobyl) had thick steel containment vessels, which, despite some reports of damage, seemed to hold up reasonably well.

Second, also unlike Chernobyl, Fukushima used water, not combustible graphite, to slow neutrons.

On the other hand, Fukushima faced systemic difficulties due to the precipitating natural disasters: After the epochal earthquake-towering tsunami sequence shut the reactors down, the electric grid died, killing the emergency cooling pumps.

Then the emergency diesel generators failed, and without cooling, the reactors quickly overheated. But with roads out and the nation tending to survivors and victims of the tsunami, the nuclear emergency festered for days, through a series of explosions, fires, bursts of radiation, and evacuations of plant workers.

At one point, just 50 workers were on hand to deal with multiple emergencies at several reactors and pools of spent fuel. The desperation was on display when helicopters tried to dump buckets of water into the fuel pools and fire trucks sprayed cooling water through explosion-blasted walls.

How many broken reactors?

Despite early fears that Fukushima was mimicking Chernobyl, it seems rather to be headed toward the less malignant TMI precedent, says West. “A big leak [like Fukushima] is not like the open-air nuclear bonfire of Chernobyl that spewed radioactive materials into the upper atmosphere. The extent of the release of radiation and the continuing difficulties with cooling of reactors and spent fuel has clearly put the Daiichi site at the TMI stage.”

As radioactive particles cross the Pacific on the jet streams, “California, Oregon, and Washington should start reporting measurable traces of radioactive materials in air samples,” says West, “but for the United States, this should be more like a Chinese test of a nuclear weapon and of no health consequence.”

Radiation has already been detected on milk and green vegetables near the reactor, and now in drinking water in Tokyo. “The Japanese will need to monitor and control agriculture products to minimize the risk to public health,” says West. “This will be similar to efforts in the United States during the 1950′s, when the U.S. was detonating nuclear weapons in Nevada,” and farmers were prohibited from selling milk for four days afterwards.

Japanese meltdowns, American reverbs

As Japan evacuated neighbors from the Fukushima plant, the U.S. Nuclear Regulatory Commission (NRC) advised American citizens in Japan to move at least 50 miles away. That’s much further than specified American evacuation plans, notes Vicki Bier, a professor of industrial engineering at the University of Wisconsin-Madison. “If the NRC is concerned up to 50 miles in Japan, that certainly calls into question emergency planning here, which is limited to 10 miles.”

On March 16, California Senators Barbara Boxer and Dianne Feinstein asked the NRC to review safety at two California plants located near earthquake faults. “Roughly 424,000 live within 50 miles of the Diablo Canyon and 7.4 million live within 50 miles of San Onofre Nuclear Generating Station,” the senators wrote.

And on Mar. 22, the Nuclear Regulatory Commission agreed to accelerate a safety review at Indian Point, a pair of reactors 30 miles from Manhattan.

Japan: How prepared, in reality?

How did such severe nuclear troubles arise in Japan, where “tsunami” was coined, and which is the world’s leader in earthquake engineering and disaster preparedness?

For starters, the tsunami was much bigger than expected. But we’ve also learned from the Associated Press (on March 24) that Japanese preparations focused on natural disasters.

Was the nuclear emergency made worse because six reactors were at one location? As we saw, radiation vented from one reactor caused the flight of workers trying to tame other reactors. But multiple siting had “always been considered to be a really good idea,” says West. “You have a collection of focused professionals with lots of resources [for example, to fight fires], so if one reactor has difficulties, you could take those excess resources and focus on that situation. … This is the first situation, where [multiple sitings] appears to need to be reexamined.”

Early reports point to a critical design failure at Fukushima, says Bier, an expert on risk assessment at nuclear plants. “They were designing for earthquake and tsunami, but not for this level of damage; you’ve got to give engineers some criteria; they can’t design for anything. They could have designed for what did happen, but they apparently decided it was too unlikely.”

Design: Where are the goalposts?

A specific weakness concerned the emergency diesel generators needed to run the pumps, which apparently were swamped by the tsunami, says Bier. “There is a lot we won’t know for months, but there is reasonable speculation about things that could be done differently at modest cost. You can’t prepare for every eventuality, but probably it would have been possible to get better protection for the diesels in a bunker or on higher ground.”

The systematic disruption and near chaos interfered with tasks like avoiding melt-downs in the pools holding spent fuel, which lack the containment usually found on reactors. As Fukushima proved, accidents can be made worse as effects are compounded: the real-life scenario included a combination of a Japan-record earthquake, massive tsunami damage, regional blackouts and radiation releases.

“The surrounding area was so damaged by earthquake and tsunami that it impeded the emergency response,” says Bier. “We have seen stories about people within the evacuation zone who could not evacuate because the roads are impassable or buildings have collapsed, and they were not sending in rescue teams because the radiation was too high. Certainly it was not anticipated that the damage would be this severe, or the radiation would be too severe to evacuate.”

 

Photo: Japan Red Cross Society

Thousands of Japanese have been evacuated from around the Fukushima Daiichi reactors; masks retard the spread of disease in close quarters. Few experts expect the need for a permanent exclusion zone, like the one in Chernobyl, around Fukushima.

Fukushima: End game

Will the six reactors at Fukushima Daiichi be dismantled, like TMI #2, or wind up inside a Chernobyl-style concrete coffin?

The three reactors that got emergency cooling with sea water are likely finished due to corrosion, not to mention possible explosion damage. “Salt water is a killer,” says Robert Rosner, professor of astronomy, astrophysics and physics at the University of Chicago. Rosner expects these reactors to be taken apart and trucked to long-term storage.

Although the age of the reactors – about 40 years – militates against spending large sums on refurbishment and updating, Japan now faces an electricity shortage, so Rosner expects one or two of the plants to return to service, at least for a while.

West, however, suggests that at least one reactor may wind up encased in concrete. “If I were an engineering manager, I would be looking at the possibility of stabilizing it to deal with all the issues” and then build an outer containment to isolate the reactor but allow service visits.

Credibility at stake

Assessing the long-term impact of Fukushima requires us to look at the technology’s unique place in the popular eye. Whether the nuclear industry likes it or not, nuclear carries plenty of emotional baggage. Nuclear physics produced the mushroom clouds over Hiroshima and Nagasaki long before it was used to make electricity. And because ionizing radiation is invisible, it’s a case where what you don’t know can hurt you.

Nuclear energy also arouses fear because power-plant neighbors cannot control it, says Nathan Hultman, an assistant professor of public policy at the University of Maryland. “A lot of research has looked at why people view risks differently, and both dread and the degree of control in nuclear are nerves that are touched very strongly. We feel safer driving cars than in an airplane, even though statistically, airplanes are much safer, because we feel in control in a car.”

 

Photos: TMI, Cherobyl:Wanrouter.

While TMI today shows the scars of its accident (reactor #2 on left melted down in 1979), Chernobyl’s gravesite (rollover) evokes a much bleaker history and deeper wounds. The thrown-together concrete enclosure may need to be replaced – a hazardous, expensive task.

The Japanese nuclear industry also faces credibility problems, Hultman notes.

“Small nuclear accidents were covered up,” says Hultman. “Often the initial reaction was ‘Everything is just fine, the situation is normal,’ then it came out there was a deeper problem. Now we are in a situation where very bad things are happening, and people are not sure what to believe.”

Hultman adds that these issues are a likely fixture in the coming debate over nuclear power. “Nuclear is not the only way to boil water to generate electricity,” he says, and the discussion of energy sources must be broader than that. “Rather than say, ‘We must have nuclear,’ we need to talk about alternatives as well.”

The Fukushima debacle could further polarize a nuclear debate that was altered by both TMI and Chernobyl, says Hultman. “There is almost a religious division. People who believe it’s good think it will be the answer to all our problems, and people who don’t like it, really really don’t like it.”

An omen for the future?

The Fukushima disaster carries striking ironies. Japan was the only country at the receiving end of atomic bombs, and studies of survivors at Hiroshima and Nagasaki have been the basis for understanding the health effects of low-level radiation.

Historically, the Fukushima disaster occurred as nuclear was gaining so much traction as a low-carbon solution to global warming that some prominent environmentalists had begun to talk nuclear. “This is going to have a big effect on the rebound toward nuclear,” says West, who adds, “We just can’t burn our forests — and coal is an old forest — forever,” due to global warming.

Even technological disasters that loom large in the short run may eventually be seen as lessons, West says. “The crash of a major aircraft … does not mean that air travel should end, it means we need to tighten up our design.”

Rosner, however, suggests that nuclear, with its potential for widespread, long-term contamination, needs to live by different rules. “When you are engineering something where the consequences, if something goes wrong, are devastating, even though the probability is very small, you need to engineer to avoid the devastation. We’ve known how to do that for 50 years, but it was always just a bit too expensive on the front end, so the decision was made: The probability is so low, we are not going to worry about it.”

As deadly American drones work the skies over Afghanistan and Pakistan, we got to wondering how similar remote-control approaches are contributing to science. In science, as in war, leaving the staff behind can slash costs and allow sustained exploration of no-go zones.

Part of the story is propulsion: New science vehicles can travel long distances through the ocean and atmosphere with minimum energy. Brains-on-board also matter: Computers enable these super-sensors to make decisions and work long stretches with little or no back-seat driving.

The result is a lot of science per gallon.

Although the vehicles we’ll look at have scientific purposes, they get major financial and technical support from the Department of Defense, proving that military and peaceful pursuits are inextricably linked in extreme environments.

If you dig the deep ocean, WHOI — the Woods Hole Oceanographic Institution on Cape Cod — is a good place to be. The renowned saltwater scientific outfit has a new, deep-water explorer that works without a lifeline.

Meet Sentry, which can take photos and make chemical and geophysical measurements down to 4,500 meters depth, and has worked two high-profile environmental issues: global warming through methane release, and BP’s Deepwater disaster.

Sentry has been used to look for “cold seeps,” regions of the seafloor that release large amounts of methane, says Chris German, WHOI’s chief scientist for deep submergence. “Cold seeps are like the overlooked younger sisters of hydrothermal vents,” the “black smokers” that release superheated fluids and anchor unique ecosystems at the sea floor, usually in mid-ocean.

Cold seeps are located closer to the continents, and “are not as spectacular thermally or geologically, but they do have some of the same chemistry,” says German, “and a lot of the same kinds of animals, even the exact same species.” Cold seeps may explain the distribution of deep-sea organisms around the ocean, he adds. “We want to understand … whether animals are using these locations as stepping stones.”

Most cold seeps were found by accident, but German thought Sentry could detect subtle chemical clues, and last October, he got to test that idea at an underwater landslide off the coast of Norway. The landslide had released pressure on a material called methane hydrate, and a large amount of methane was bubbling from the seafloor mud, creating a “mud volcano.”

Methane is a much more powerful greenhouse gas than carbon dioxide, and given the staggering amount of methane held in methane hydrates, such releases could create a nightmare feedback: warming releases methane, which traps more heat, causing more warming that releases more methane.

Getting engulfed

By prowling around the known cold seep near Norway, German confirmed the detection hypothesis.

Then, the day after Sentry returned to Woods Hole, a real-world opportunity appeared for the new technique.

Biologist Charles Fisher at Penn State was about to embark on a mission into the aftermath of BP’s blowout in the Gulf of Mexico, and he wanted help locating a coral patch to compare to another he’d already located 1,200 meters deep, 11 kilometers southwest of the blowout.

That coral was coated with a brown goop that looked suspiciously like crude oil. Could Sentry locate, for long-term comparison purposes, a similar coral outside the oil plume?

Fisher was part of a National Science Foundation-sponsored “rapid response” cruise to the Gulf, but German was still unpacking. “We’d have two weeks to turn around and get going, and I went to our guys Monday morning and asked, ‘Can you do this?’”

The maintenance crew figured out who would miss what weekend, and they agreed to do it, German says.

Cold seeps and deepwater coral in the Gulf of Mexico are linked, German explains, because the coral live on bare rock, which is often carbonate, and carbonate rock forms at cold seeps when methane is oxidized into carbon dioxide. “So beneath every healthy deep coral, is an active or historic cold seep.”

Suddenly, a theoretically interesting search technique became relevant to the biggest American oil spill in a century.

“Flying” with a map

Based on oil-industry data about the sea bottom, Sentry visited one location southeast of the Macondo well and found no coral. But at the second location, German says, “We hit pay dirt. We flew backward and forward, and found an active cold seep and evidence for tube worms, mussels and coral.”

Ocean-floor research seldom moves so fast, German says, and within hours, he was one of three people to visit the spot in Alvin. “In 36 hours, we went from nothing other than a hunch, to having a topographic map and photos,” German says. “We dove to the sea floor, and there was no mysterious driving around in the dark. Within 15 minutes, we drove to the site because we had a perfect map of where to go.”

In fact, German was holding a fresh, glossy photo of the target, taken less than two days previously.

Sub-terra cognita? Not!

And so is the ocean bottom, as people often say, still less familiar than the far side of the moon? German insists that it still is, despite years of research and an increasingly capable flotilla of deep-sea ships. “In December, in the Gulf, I could see at least 10 to 20 oil rigs… but I’m pretty sure, driving across that seafloor a couple of hours offshore from the United States, that nobody ever laid eyes on it before.”

A recent survey of marine biodiversity shows a chain of ignorance stretching across the Pacific, located near regions of extremely high biodiversity near the Philippines and Australia, German says. “In many of those locations, they’re 300 miles square, there have been fewer than 50 biological measurements in the history of the ocean. This is a chain across the South Pacific ocean, the single biggest contiguous ecosystem on the planet, and it has not been studied.”

And that’s the rule, not the exception, German says. “Close to one-half of the planet is at least 3,000 meters deep, and it’s much further away [and deeper] than the Gulf. From satellite altimetry we have an idea where the bumps are on the seabed, but we don’t know what’s going on; we have a vanishingly small idea.”

Deep water may be the sexiest place in oceanography, but long-term studies are also difficult and expensive in shallow waters, especially if they are remote, icy, stormy, or all three. Propellers, the standard way of moving through water, require a lot of energy and quickly drain batteries on artificial fish.

Gliding — think of soaring like a hawk as opposed to flapping like a sparrow — is a much more conservative approach.

And gliding is the MO of Seaglider, a project built by the University of Washington with money from the Office of Naval Research and the National Science Foundation. Using battery power, the glider alters its buoyancy, causing it to rise or fall through the water. By altering its center of gravity and adjusting its fins, the metal fish moves horizontally with minimal amounts of electric current.

How minimal? In 2009, a Seaglider traveled a record 3,050 miles through the North Pacific during a 9-month journey, without the caress of a human hand or an electric transfusion.

Costing “only” about $100,000 apiece, about 60 gliders are working around the globe, says Craig Lee, a principal oceanographer at UW’s Applied Physics Laboratory, recording basics like temperature, salinity, dissolved oxygen and optical characteristics of its surroundings.

In 2008, south of Iceland, gliders and floats studied carbon uptake by phytoplankton — floating plants that bloom in spring and play a major role in the global carbon cycle. The goal was to follow “parcels” of water during the entire bloom — which ends after some weeks when plankton are eaten or sink in the water. Both processes can remove carbon dioxide from the atmosphere for long-term storage, and therefore have implications for global warming.

“We were trying to learn what drives the carbon flow,” says Lee. “Nobody had done this before: the Seagliders and the buoys had the persistence, the ability to be there for the entire duration of the bloom. You would have to schedule a ship one year ahead, and … if you got there on time, it would be too expensive to keep the ship out there for the whole bloom.”

If ice is nice, under ice is nicer!

In 2009, a Seaglider spent 51 days in Davis Strait, the frigid water separating Greenland and Baffin Island, traveling more than 450 miles under the ice. The Strait is a chief source of melt-water from the frozen Arctic Ocean.

Climatologists worry that a rush of cold, fresh water through the Strait could alter the warm Gulf Stream and freeze Northern Europe.

Getting measurements from Davis Strait is expensive and dangerous, especially considering how much of it is under ice. But the Seaglider did just fine, says Lee. “This was very exciting, that ability to stay out there for a long time, and the ability to get to places that otherwise would be difficult. In winter in the North Atlantic, nobody wants to be there…”

The fish navigated under the ice using five anchored sonar beacons that created an undersea version of GPS, Lee says. Ten times, using its software, the glider found holes in the ice, poked its nose through them, and phoned home via satellite telephone. “It tries to sense ice by looking at the temperature of the water,” says Lee. “It emits a ping and tries determine whether ice is overhead, and it has a climate map that tells it, for a given position at a given time, is ice likely to be overhead? Using all that information, it decides whether to surface.”

During those famous North Atlantic storms, “It just keeps working, it does just fine, continues to navigate, continues to report. We’ve been in 40-foot seas, with 60- to 80-knot winds, and everybody’s happy, although it takes a little longer to get a phone call through.”

The glider carries a quarter for the phone call, but no Dramamine…

A fruit of the military’s desire to see everything from a safe vantage, Global Hawk is a secretive, high-flying, pilot-free jet that can fly at 60,000 feet for 30 hours, non-stop.

For its occasional forays into peaceful work, Global Hawk carries a large cargo of scientific instruments that can monitor light, pollution, ozone, water vapor, weather, clouds, incoming and outgoing radiation, even particles smaller than 1 millionth of a meter across.

The Hawk, which flew scientific missions from NASA’s Dryden Flight Research Center in California in April, 2010, can also be used for earth observation, such as tracking algal blooms in the ocean, vegetation on land, and various resource issues.

Hawk has tracked pollution from Asia above the North Pacific as it moves toward North America and looked at large-scale atmospheric circulation, which influences weather and the distribution of radiation-blocking high-altitude ozone.

We could not get through to a source at the National Oceanic and Atmospheric Administration, which plays a role in Hawk’s science, but we grabbed a press release issued after Hawk’s first environmental flight.

According to Paul Newman, an atmospheric scientist from NASA, “The Global Hawk is a revolutionary aircraft for science because of its enormous range and endurance. No other science platform provides this much range and time to sample rapidly evolving atmospheric phenomena. This mission is our first opportunity to demonstrate the unique capabilities of this plane, while gathering atmospheric data in a region that is poorly sampled.”

In their quest for data on the deep, scientists have gotten a trickle of info from sensors attached to deep-diving marine mammals. In November, 2009, the Scripps Institution of Oceanography launched SOLO TREC (Sounding Oceanographic Lagrangrian Observer Thermal RECharging vehicles; glad you asked?), a bobber that can sink 500 meters into the ocean, then return to the surface to report via satellite to scientists who may prefer sipping lattes at a Java Joint to crowding the rail on a topsy-turvy research ship.

Let’s call this Solo, and let’s agree that it’s a strange vessel. Solo can adjust its buoyancy, but lacks propellers and cannot drive laterally, so its location is at the mercy of the currents.

Solo records basic ocean conditions, but the real accomplishment is proving that its power system needs no recharging and could, theoretically, operate more or less forever – or at least until it breaks or barnacles or plants foul the fish up and slow it down.

Solo had already completed 300 dives by March, 2010, and although it sounds like a perpetual motion machine, it actually sucks its energy from the ocean as it rises toward the surface:

According to Yi Chao of the Jet Propulsion Lab, a Solo principal investigator, “This technology to harvest energy from the ocean will have huge implications for how we can measure and monitor the ocean and its influence on climate.”

Funded by NASA and the U.S. Navy, Solo’s technology is also obviously useful for monitoring animals and the movement of ships and submarines.

Historians tell us the Spanish introduced pressurized water systems to the New World. But a new study indicates that the Maya were building pressurized pipes between about 450 and 750 AD, in Palenque, a major Mayan city in modern-day Mexico.

The Maya built a large number of cities in the Yucatan, Guatemala and Belize, before their cities were suddenly and mysteriously abandoned around 800. The Maya, whose descendants still live in the region, wrote with hieroglyphs, had extensive knowledge of astronomy, and their economy was strong enough to support cities such as Palenque, Chichen Itza and Cobal.

Until now, nobody had found evidence for pre-Spanish pressurized water in the New World, say the two authors of the new study.

The evidence takes the form of a narrow constriction in the underground Piedras Bolas aqueduct that routed water from a spring into Palenque. Unlike many Mayan cities, Palenque was built in low mountains, with only about 2,200 hectares of reasonably flat land. Untamed streams would gobble valuable real estate, so the Maya built limestone conduits to rout water through the city.

In some cases, the Maya plastered the inside of conduits with stucco to prevent leaks. And like modern builders, they Maya covered the conduits with stones that paved city streets and plazas.

Streaming, but not video

The suggestive constriction was six meters below the spring that supplied the stone pipe, and that height differential put the water under pressure, says co-author Christopher Duffy, a professor of civil and environmental engineering at Penn State University. The system is “analogous to a modern water distribution system. The water tower produces a ‘hydraulic head,’ or water pressure. The pipes go underground, and back up into the home, where water flows under pressure.”

The small opening at the bottom allowed the Maya to close off the conduit, so it would stay full of water. Air in the system will neutralize the hydraulic head, Duffy says.

Unfortunately, the Palenque site has been disturbed, and tantalizing questions remain, Duffy says. “We don’t know how they distributed the water from this point, but we can’t see any other purpose, other than as a control point in the buried conduit.”

Paving paradise to put up a … fountain — or a toilet?

Archaeologists already know that the Maya had an extensive irrigation system, fed by nine streams that ran through Palenque to the fields below.

The constricted conduit, one of nine, had a capacity of about 68,000 liters, and it alone could have stored enough water to supply scanty rations for several thousand people for a week during the dry season.

The pressurized pipe could have supplied a fountain where people could dip jars to collect drinking water. But the putative fountain was “probably beautiful,” says co-author Kirk French, a lecturer in anthropology at Penn State. “Everything the Maya did at Palenque was over the top, grandiose, in art and architecture.”

Fountains also serve a social purpose, says French. “They are in a central part of the city, where people can fill jugs and socialize. It’s funny, we refer to ‘water-cooler conversations,’ but it seems this has been going on for a very long time.”

Did the Maya’s pressurized plumbing have a more, er, “sanitary” function? “We don’t know the exact application,” admits Duffy, who specializes in hydrology, “although we were recently told, after the paper came out, that there are sweat baths, and perhaps toilets, in the palace at Palenque.”

In fact, the palace has “four toilet-like features,” French says, “They are in a line, at the right height, and share the same drain, but it’s hard to prove that they are toilets.”

The sanity of sanitation

Toilets or not, the newly discovered plumbing shows that the Maya “are better engineers than they ever got credit for,” Duffy says. Although the Maya may have never seen pressurized water flow in nature, people are inventive, especially when it comes to something as important as water.

“We think this is the first example in the New World, but a lot more will probably be discovered,” says Duffy. “The Maya built like the Romans. They were practical. They would build, if it failed, they would build again. It’s a standard engineering strategy. Do something, fail, learn, and do it again.”

– David J. Tenenbaum