Tang Shipwreck

The world economy in the ninth century had two powerful engines. One was Tang dynasty China, an empire stretching from the South China Sea to the borders of Persia, with ports open to foreign traders from far and wide. The Tang welcomed diverse people to its capital, Changan, the site of modern-day Xian, and multiethnic groups lived side by side in a city of a million—a population unmatched by a Western city until London in the early 19th century. Then, as today, China was an economic powerhouse—and much of that power was built on trade.

The other economic engine was Baghdad, capital of the Abbasid dynasty from 762 onward. That dynasty inherited the Muslim world in the Middle East; by 750 it had spread as far as the Indus River to the east and Spain to the west, bringing with it trade, commerce, and the religion of Islam (the Prophet Muhammad himself had been a merchant).


A 1,200-year-old shipwreck opens a window on ancient global trade.



Linking the two economic powerhouses were the Silk Road and its watery counterpart, the Maritime Silk Route. The overland road gets all the attention, but ships had likely been plying the seas between China and the Persian Gulf since the time of Christ. In tune with the cycle of the monsoon winds, this network of sea-lanes and harbors bound East and West in a continuous exchange of goods and ideas.

Tang China was hungry for fine textiles, pearls, coral, and aromatic woods from Persia, East Africa, and India. In return, China traded paper, ink, and above all, silk. Silk, light and easily rolled up, could travel overland. But by the ninth century, ceramics from China had grown popular as well, and camels were not well suited for transporting crockery (think of those humps). So increasing quantities of the dishes and plates that held the meals of wealthy Persian Gulf merchants arrived by sea in Arab, Persian, and Indian ships.

It was a long and perilous journey. And some­times a ship just vanished, like a plane off a radar screen.

Since time immemorial, ships have come to grief in the Gelasa Strait, a funnel-shaped passage between the small Indonesian islands of Bangka and Belitung, where turquoise waters conceal a maze of submerged rocks and reefs. Despite the dangers, sea cucumber divers were working the area a decade ago when, 51 feet down, they came across a coral block with ceramics embedded in it. They pulled several intact bowls from inside a large jar, took them ashore, and sold them.

The divers had stumbled upon the most impor­tant marine archaeological discovery ever made in Southeast Asia: a ninth-century Arab dhow filled with more than 60,000 handmade pieces of Tang dynasty gold, silver, and ceramics. The ship and its cargo, now referred to as the Belitung wreck, were like a time capsule of proof that Tang China, like China today, mass-produced trade goods and exported them by sea. Working in shifts until the monsoon stopped them, a team of divers retrieved the ancient artifacts.

The treasure—much of it, anyway—turned out to be the Tang equivalent of Fiestaware: so-called Changsha bowls, named after the Changsha kilns in Hunan where they were produced. Tall stoneware jars served as ninth-century shipping containers; each could hold more than a hundred nested bowls that might originally have been padded with rice straw, a sort of organic bubble wrap. Scholars already knew that such simple, functional tea bowls had been exported worldwide from the eighth to the tenth centuries: Shards of them had been found at sites as far afield as Indonesia and Persia. But few of the bowls had ever been found intact.


Now the Java Sea had yielded up a shipload, many perfectly preserved—protected in the stoneware jars from the scouring action of sand on the seafloor. Sponged clean, their glazes shone as brightly as the day they were fired.

The handmade bowls give evidence of "factory-like production," says John Miksic, an American professor at Singapore's National University who is an expert on Southeast Asian archaeology. They are the earliest known exported examples of their kind. "The cargo also implies an organizer with managerial skill," Miksic says, "and huge quantities of imported raw materials." Cobalt for blue-and-white ceramics, for example, came from Iran; it was not recovered from ore in China until much later.

Although Arab mariners clearly plied the Maritime Silk Route, trading on a large scale over great distances, "this is the first Arab dhow discovered in Southeast Asian waters," says John Guy, senior curator of South and Southeast Asian Art at the Metropolitan Museum in New York, "and the richest and largest consignment of early ninth-century southern Chinese gold and ceramics ever discovered in a single hoard."

A reconstruction suggests the craft was similar to a kind of sailing vessel still found in Oman and known as a baitl qarib. Almost 60 feet long, with a raked prow and stern, it was built of Afri­can and Indian wood and fitted with a square sail. Its most distinctive feature was that instead of being held together with dowels or nails, its planks and beams were literally sewn together, probably with coir, a coconut-husk fiber.

The dhow's port of departure and destination are still uncertain. No logbooks survived, no bills of lading, no maps. But most scholars believe that it was bound for the Middle East, possibly the Iraqi port city of Al Basrah (now Basra). It probably set sail from Guangzhou, the largest of the ports linked by the Maritime Silk Route. In the ninth century an estimated 10,000 foreign traders and merchants, many of them Arabs and Persians, lived in Guangzhou.

Among the tens of thousands of Changsha bowls found in the wreck, one was inscribed with this message: "the 16th day of the seventh month of the second year of the Baoli reign," or A.D. 826 on the Western calendar. This is almost certainly when the bowl was fired. Then, as now, goods did not sit around on the wharf for long, so the ship probably embarked not long afterward.

The serial nature of the cargo (along with the bowls, it included 763 identical inkpots, 915 spice jars of various sizes, 1,635 ewers) and the geographic diversity of its production (from at least five kilns widely dispersed over China) suggest that these were export items made to order. Decorations show the eclecticism of the global market. There is something for everyone: Buddhist lotus symbols and motifs from Central Asia and Persia. Objects bearing geometric decorations and Koranic inscriptions were clearly aimed at the Islamic market. White ceramicware as well as green-splashed bowls and ewers are known to have been popular in Iran. One bowl was inscribed with five loose vertical lines, inter­preted by some scholars as a symbol whose meaning resonates powerfully in today's world: Allah.

Like the shiploads of sneakers or electronics stamped "Made in China" today, most of the items recovered from the dhow were trade goods. But at the stern of the ship, divers found a trove of gold and silver and high-grade ceramics whose significance is more mysterious.

Peeling back a cloud of white, acid-free paper, Alvin Chia holds up a cup in gloved hands. "This is the largest Tang dynasty gold cup ever found," he says. Chia is an executive with Singapore's Sentosa Leisure Group, which joined with the Singapore government to beat out several museums and bought the entire cargo in 2005 for more than $30 million. It may one day be the core of a Maritime Silk Route museum.

Chia points out that two men depicted on the cup's thumb plate look Central Asian rather than Chinese, with long, curly hair and thick beards. On the cup's side panels are figures in motion: a Persian dancer clapping her hands above her head, musicians playing various instruments. In Tang China, Chia explains, music and dance from eastern Persia were all the rage.

A large, exquisitely decorated silver flask might offer a clue to the purpose of the hoard. "See the pair of mandarin ducks?" Chia asks. "They are a symbol of matrimonial harmony. On ornamental boxes everything is also in pairs: a pair of birds, a pair of deer, a pair of ibexes." Perhaps these were gifts for a royal wedding in the Persian Gulf—a bride's treasure of the sort rarely seen outside of China.



Since China first began trading with the world more than 2,000 years ago, it has opened and closed like a clamshell. During the Tang dynasty the clamshell was wide open and remained so for many centuries. A string of inventions—gun­powder, paper, printing, and cast iron—had set China on course to become the world's leading economic power. Trade with the West had steadily expanded, with Chinese seafarers taking an increasingly dominant role.

When the great admiral Zheng He set sail in 1405 with a fleet of 317 ships, China ruled the waves. "If you had been sitting in a spaceship looking down on Earth, and you had observed developments from the ninth to the 15th century," says John Miksic, "you would have thought that the Chinese would take the next step—explore the Atlantic and become the dominant world culture." But throughout Chinese history, there has been another, equally powerful force at work: a distrust of merchants and the foreign influences they import, dating back to Confucius, who believed trade and commerce should not dictate Chinese culture and values.

In A.D. 878, little more than half a century after the Belitung ship sank, a rebel leader named Huang Chao burned and pillaged Guangzhou, killing tens of thousands of Muslims, Jews, Christians, and Parsis. And not long after Zheng He's voyages, when Columbus reached the New World, the Confucian worldview won the day; China burned its fleet and turned inward. The Silk Road and the Maritime Silk Route, which had linked China to the world, lapsed into disuse. The Portuguese entered the Indian Ocean, and by the late 17th and early 18th centuries, Europe had begun to dominate world trade. "The whole of world history would have been different if the Chinese had not gone into their shell for 500 years," Miksic says.

Now China competes with India to be the world's workshop. China is open as never before and once again trading with its ancient partners in the Middle East. Iran, for instance, supplies 12 percent of China's oil. In return, Beijing provides machinery and locomotives, builds subways and railroads, and helps Tehran exploit its vast mineral resources, closing the loop from the ninth century, when cobalt was shipped from Persia to China for the blue-and-white ceramics found on the Belitung ship.

"The ancient networks are restored through industries and factories in a world that is now globalized," says Wang Gungwu, a historian at the National University of Singapore.

For how long this time is anybody's guess. 

Bagpipe Wood Goes Green; African Villagers to Profit

In a move that should be music to the ears of forest conservationists, the African blackwood tree, also known as mpingo, is getting increased protection in Tanzania.

Two remote villages in the East African country will harvest and sell eco-certified mpingo, a slow-growing tree that is highly prized for making clarinets, oboes, and bagpipes.

It is the first time that local communities in Africa have obtained certification from the Forest Stewardship Council (FSC), an international nonprofit organization that encourages responsible forest management.

Most FSC-certified forests around the world are commercially owned temperate or boreal forests found in cooler climes.

"This is the first time a rural community in Tanzania has had the chance to really benefit from their local forests," said Steve Ball, the international coordinator of the Mpingo Conservation Project in Tanzania.

Previously, "well-connected outside loggers … have taken all the loot for minimal payment," Ball said.

Traditional Uses

African blackwood has been overharvested across Africa by loggers who value it for its dark, lustrous heartwood.

It's been heavily logged out in Kenya, where it's now commercially extinct, and northern Tanzania.

But the thorny tree, which is smaller than most other timber species, is still common in southeastern Tanzania and northern Mozambique, where most harvesting now takes place.

Illegal logging, however, is rampant in Tanzania. One 2005 study by TRAFFIC, the wildlife-trade monitoring network, suggested that 96 percent of timber extracted from southeastern Tanzania was illegally logged.

Blackwood is the preferred source material for ethnic Makonde wood carvers in Tanzania.

The tree is also used in various forms of traditional medicine, especially in childbirth—a mulch of mpringo leaves is believed to make newborn babies strong.

But the wood is most highly prized for making musical instruments, due to its density and high oil content, which protects woodwind instruments from the degrading effects of spit and moisture carried in the breath of the player.

"There is also a strong element of acquired market preference," Ball said.

"Musicians expect a black instrument, so manufacturers make sure they deliver them one."

Somewhere between 65,000 and 100,000 wooden clarinets and oboes are produced worldwide each year, as well as under 10,000 bagpipes components, according to Ball.

"Ethically Sourced"

The two villages—Kikole and Kisangi—are located in the coastal Kilwa district in southeastern Tanzania. With between 1,000 and 1,500 inhabitants each, the villages are extremely poor, with average household incomes under a dollar (U.S.) a day.

Before the Mpingo Conservation Project began working in Kilwa in 2004, loggers had to pay the local village a hundred Tanzanian shillings (U.S. $0.08) per log taken out of the surrounding forests.

Loggers were also required to pay a government royalty fee of about 12,000 Tanzanian shillings (U.S. $9.60) per log of blackwood. But Ball said many loggers simply ignored the fee.

Under a new government-backed program, however, local communities can assume ownership of the forests and profit from timber sales, as long as they manage the forests sustainably.

With the timber labeled as "ethically sourced" by the FSC, the villages of Kikole and Kisangi will be able to charge up to 25,000 Tanzanian shillings (U.S. $20) per blackwood log, Ball said.

"As the market develops, we hope that communities should in fact be able to charge a significant premium on top of that, potentially doubling the price of certified blackwood timber or more," he said.

Mwinyimkuu Awadhi is the chairman of Kikole village.

The project has "given us a good education on how to manage our forests," he said.

"Fortunately, we have plentiful stocks of mpingo, so we can make the most of this opportunity."

The first timber was harvested this spring. Because the wood must then be properly dried—a process that takes at least one year—the first FSC-certified blackwood instruments are expected to be available sometime in 201

Brown Dwarf Weather Report: Cloudy

Astronomers have made an interplanetary weather report, spotting brightness alterations in a brown dwarf's atmosphere. The brown dwarf in question is SIMP 0136, the brightest "T dwarf" in the northern hemisphere.

Although SIMP 0136 is classed as a 'failed star', have astronomers uncovered a phenomenon more commonly found in planetary atmospheres?

Etienne Artigau and his team at the Gemini South Observatory carried out an observing campaign for five days and realized that not only was SIMP 0136 varying in brightness, its atmosphere was changing. On each day, dark and light patches moved across its surface, indicating the motion of dust clouds.

Brown dwarfs are often considered to be 'failed stars' as they are too lightweight to allow nuclear containment in the core, facilitating fusion. The fusing of nuclei in the cores of stars generate energy and outward pressure, balancing out the inward pull of gravity. Brown dwarfs never enjoyed fusion (or if they did, it didn't last very long), so the cores of these sub-stellar bodies become 'electron degenerate' before any fusion is possible. This electron degeneracy counters the inward gravitational pressure, thereby maintaining the brown dwarfs shape.

So, they're not stars, but they can't really be called planets either. They have convective interiors (like our sun's convection zone) and lack any chemical differentiation. You can see why they can't be classed as a "star" (even though they are still ranked by stellar classifications), but they can't be classed as planets; they are in a no-mans land, too big to be a planet, too small to be a star.

That said, they certainly have more star-like properties than planet-like properties, hence the almost derogatory term 'failed star', a term I took great displeasure with in a recent light-hearted Astroengine article:

Why is the term “failed star” synonymous with brown dwarfs? On the one hand, brown dwarfs lack the mass to sustain nuclear fusion in their cores. On the other hand, who said brown dwarfs were trying to be stars? Who ever said that becoming a star was the pinnacle of stellar living? Perhaps brown dwarfs are perfectly happy the way they are. In a world of equality and political correctness, brown dwarfs could be viewed as “over-achieving Jupiters”, or gas supergiants. --Astroengine.com

Going back to Artigau's study of SIMP 0136, is this brown dwarf exhibiting a planet-like characteristic? This object is cool enough for solid grains to form in its atmosphere, so these brightness changes could indicate changes in atmospheric conditions. Is this a brown dwarf weather system?

Calling it "weather" is probably a bit strong, but it's certainly something to consider before calling brown dwarfs a failure in the stellar department.

Launch Could Be Wednesday

NASA is repairing a leaky hydrogen gas line on Endeavour's fuel tank in hopes of launching the shuttle on its space station construction mission Wednesday, four days after the first try was called off.

But another NASA mission, involving a pair of science spacecraft bound for the moon, is scheduled to blast off Wednesday. Top space agency officials will decide Monday whether to bump the moon mission to make way for Endeavour.

Mission management team chairman LeRoy Cain said it's likely Endeavour will go first — if the repair effort goes well, no other shuttle problems crop up and the weather cooperates.

"A lot of things have to go our way," Cain said.

Hydrogen gas began leaking from a vent line hookup on Endeavour's external tank during fueling early Saturday, and the countdown was halted just hours before the scheduled morning liftoff.

The same kind of leak postponed a shuttle launch in March. Technicians replaced the vent line hookup and a pair of Teflon seals back then, and the leak did not recur. NASA is hoping for similar results this time. The hookup and seal replacements on Endeavour's tank were expected to be completed Monday morning.Engineers never determined why the vent line leaked in March. Finding the cause has taken on new urgency.

NASA finds itself in the difficult and unusual position of having to choose between two space missions that both have a relatively short time to launch.

Endeavour must fly by this weekend, otherwise the mission to deliver the final piece of the Japanese space station lab must wait until mid-July because of unfavorable sun angles that would heat up the shuttle. The moon mission -- NASA's first in a decade -- must be launched by Saturday as well, otherwise it will have to wait until the end of the month for another shot.

One of the lunar spacecraft, an orbiter, is designed to map the moon so NASA can determine where best to put an outpost for astronauts in years to come. The other craft will smash into a shadowed crater at one of the moon's poles to check for signs of frozen water.

Cain said NASA could maximize the number of launch attempts for both missions if it tries to launch Endeavour on Wednesday. The Air Force would need a day to reconfigure its systems for the unmanned Atlas V rocket, then NASA could try to launch its lunar spacecraft Friday, with Saturday as a backup.

Endeavour's seven astronauts were sticking around Kennedy Space Center, to be ready to go whenever they get the call.

If the shuttle launch ends up bumping into July, there would be a ripple effect for the following few shuttle launches, Cain said. But the space agency could still meet a 2010 deadline, he said, for finishing the International Space Station and retiring the three remaining shuttles. At that point, NASA would focus on new spacecraft intended for landing astronauts on the moon by 2020.

As for the launch weather, forecasters put the odds of favorable conditions at 70 percent for Endeavour early Wednesday morning. The Atlas rocket with the lunar spacecraft, on the other hand, would have a 60 percent chance of taking off in its Wednesday afternoon slot, because of the increased likelihood of storm clouds.NASA is pushing to launch Endeavour as soon as possible because of the demanding lineup of shuttle flights over the next 1 1/2 years. The space agency is under presidential direction to retire its three remaining shuttles and complete the station by the end of 2010 if possible.

"It has a lot of downstream effects if we punt to July," Moses said. "Every launch delay pushes the next one back. It's not the end of the world, but it's not the simplest thing to do."

Eight shuttle missions remain, including Endeavour's upcoming trip. Each one is dedicated to finishing the station, currently 81 percent complete, and hauling up supplies, spare parts and experiments.

The space station will be supplied over the long haul by unmanned Russian, European and Japanese craft, but none as big as the shuttle. That's why NASA needs to deliver large spare parts now, while the shuttles are still flying.

Until NASA's new spaceship is ready to carry passengers -- which isn't expected to happen before 2015 -- U.S. astronauts will hitch rides back and forth on the cramped Russian Soyuz spacecraft for up to $51 million a person.

Antivenoms Can't Stop Deadly Jellyfish Sting

Box jellyfish kill around one person in Australia every 2 to 3 years, mainly children. And a long-used box jellyfish antivenom is unlikely to actually save lives, suggests new Australian research.

A long-used box jellyfish antivenom is unlikely to actually save lives, suggests new Australian research. And one expert says findings like this mean we need to improve our testing of antivenom effectiveness.

A team publishing online in the journal Toxicology Letters say venom from the box jellyfish acts so rapidly that any antivenom is unlikely to be protective.

"The box jellyfish is by far the most lethal organism in the world," says clinical toxicologist Geoff Isbister of Menzies School of Health Research in Darwin.

He says a sting from a box jellyfish is like "millions of hyperdermic injections of venom" and can cause cardiac arrest and death.

Isbister says there has long been a question mark over the clinical effectiveness of CSL's antivenom for the Australian box jellyfish, Chironex fleckeri, which has been used since the 1970s.

"There's never been a case where someone could say that antivenom saved a life," said Isbister.He says people given the antivenom have still died, and others have survived with resuscitation, even without the antivenom.

Isbister and colleagues found that when CSL antivenom was mixed with venom and injected into the rat, all the toxins in the venom were bound, and the rat did not die.

But, says Isbister, in real life, people are exposed to the venom first, before the antivenom.

To mimic this situation, the researchers administered the venom first, and found the rat died within 30 seconds to 2 minutes.

"The rats died so quickly you couldn't even give them the antivenom fast enough," said Isbister.

They even found that when they gave the antivenom first, it did not protect against the venom.

Isbister says the findings suggest the antivenom was unlikely to be effective.

"Ultimately in the real setting, even giving antivenom after they've been stung is probably not going to work," said Isbister.

Isbister said other studies are finding similar limitations with other antivenoms.

He says his own research suggests antivenom is ineffective in relieving the pain of redback spider bite. As a result, he and colleagues have started an NHMRC-funded placebo-randomised controlled trial of redback antivenom.

Other research on snake antivenom shows it does not help stop bleeding, says Isbister.

He says one reason it is important to make sure antivenom is effective in patients is to ensure the benefits outweigh the risks. "Antivenom is not risk free. It can cause anaphylaxis and allergic reactions," said Isbister.

CSL says it needs more time to analyze the new research."We are always interested to see papers like this and we take account of their findings," a company spokesperson said. "However," they added, "we cannot make conclusions about what should happen in a clinical setting as a result."

"The clinical management of box jellyfish envenomation is highly dependent on the circumstances, for example remoteness of the incident, and is a matter for the treating doctor to decide."

The ultimate evidence that box jellyfish antivenom is ineffective in patients would come from a placebo-controlled randomized controlled trial, in which some patients are given antivenom, and some aren't.

But, given the deadly nature of box jellyfish venom, Isbister says this would be regarded as unethical.

Isbister says he has been criticized by some who believe his negative comments about antivenoms are threatening antivenom research and production. But he emphasizes that some antivenom is really important, such as that which protects against the neurotoxic effects of taipan bite.

He would like more realistic tests to be carried out in the research and development of antivenoms.

"You can't assume that's something is going to be effective even if it binds the toxins," said Isbister.

Box jellyfish kill around one person in Australia every 2 to 3 years, mainly children. For now, prevention is the best cure.

"Don't let children swim when there's jellyfish around," Isbister said.

Tech Could Hide Submarines

A new invisibility cloak for sound could help doctors find tiny tumors or hide submarines from enemy sonar.

"Our focus is not about dampening noise, but to guide sound waves around structures," said Nicholas Fang, a professor a the University of Illinois at Urbana Champaign and coauthor, along with Shu Zhang and Leilei Yin, on a paper that appears in the journal Physical Review Letters.

For example, "if we have a coating on a submarine that bends acoustics waves before they hit the surface, guiding them around the submarine smoothly, then you won't be able to detect a submarine using sonar."

The same technology that could render a military submarine invisible to sonar could also be used to create high-definition, in-utero baby pictures or detect previously undetectable, tiny tumors.

Invisibility cloaks, whether for sound or light, both manipulate waves. Harry Potter-style invisibility cloaks manipulate beams of light. Acoustic invisibility cloaks manipulate waves of pressure. Whatever the wave type, the principle is basically the same; bend a wave around an object without breaking it.The concept is the same, but the design is quite different. One of the many differences between the two types of waves is size.

Sound waves are larger than electromagnetic waves. To manipulate either wave requires structures many times smaller than the size of the wave. Because the properties of the material are determined by their physical structure and not their chemical make-up, as they traditionally are, they are called metamaterials.

"If you need to build an ultrasonic metamaterial, the dimension of the physical structure is tens or hundreds of microns," said Fang. "Compare that with optical metamaterials, and you are talking about hundreds of nanometers. That makes it a lot more amenable for research."

The sonic invisibility cloak works a lot like a musical instrument.



Musical instruments amplify sound waves using shaped cavities. The sonic metamaterial uses cubes and octagons to create holes that can then bend the wave around the structure. The most obvious application would be as a coating for submarines that want to avoid detection from enemy sonar.Besides bending waves around a structure, the CD-sized metamaterial can also focus sound waves into a sub-millimeter-sized area, an area smaller than traditional ultrasound machines can currently see. Known as a super lens, it could enable doctors to see babies in utero in much higher definition or detect tumors that are currently too small for ultrasonic detection.

"We have seen some very exciting demonstrations," said Fang. "But to make this as a practical structure we need another three to five years."

Other researchers are excited by the development.

"This is one of the very first metamaterials that has been designed to work and actually do something useful for sound waves instead of electromagnetic waves," said Steven Cummer, a professor at Duke University who helped develop the original invisibility cloak in 2005.

"I would say that the Illinois design for two-dimensional acoustic metamaterials is pretty straightforward to manufacture. I certainly hope that it can be transitioned to an actual application," said Cummer.

Socompa

Socompa is a stratovolcano at the border of Argentina and Chile. A large composite complex, Socompa is best known for its large debris avalanche deposit, widely accepted as the best preserved example of this type deposit in the world. The volcano is difficult to reach - either from the north along dirt tracks south of the Miscanti Pass, or from the west via the Escondida copper mine. Both routes require a full-day's driving and for any reasonable amount of time to be spent at Socompa would need significant planning.

The western rim of the volcano borders the Monturaqui Basin, which is draped with the large debris avalanche deposit. Escondida mining currently has a network of roads covering this area, from beneath which they pump ground water for use at the nearby copper mine. The southern margin of the deposit is bordered by the Antofagasta to Salta trans-Andean railway, although this is rarely used.

Socompa Debris Avalanche Deposit

The debris avalanche deposit is distinct in that its volume sets it apart from most other known terrestrial debris avalanches. Prior to the 1980 eruption of Mount St. Helens, many debris avalanches were miss-interpreted, and the Socompa deposit was initially linked to pyroclastic flow products of a cataclysmic eruption. It was first recognised as resulting from volcano collapse by Peter Francis and others in 1985, when they described the major features and reclassified it as a debris avalanche deposit. Subsequent works studied the deposit itself in more detail. It contains many features expected from a debris avalanche, including large-volume, rotated and slumped toreva blocks and hummocky topography. There is also evidence for a magmatic component (Bezymianny-type collapse) from the breadcrust texture of large dacitic blocks and a thin pyroclastic flow deposit. A large amphitheatre, open at 70° and with a width of 10 km at its mouth, marks the site of collapse on the remaining edifice. Since the failure, some 7000 years ago, this has been partially filled by subsequent lavas and pyroclastics.

The most striking aspects of the deposit are its volume, deposition and composition. The deposit has a volume of 25 km2 (10 sq mi) – around an order of magnitude greater than the Mount St. Helens collapse - in addition to 11 km2 (4 sq mi) of toreva blocks at the mouth of the amphitheatre. While a significant component clearly originated from the ancestral Socompa edifice, there are also large amounts of ignimbrite and gravels which have been shown to have come from the substrata immediately below Socompa. By volume, these make up the bulk (80%) of the deposit. Additionally, despite originating at the lowest part of the failure zone, these units travelled the furthest distance and are found at the base of the deposit. The avalanche travelled down the regional slope for part of its course before mounting at least 250 m (820 ft) of topography near to its distal end, suggesting a high speed of emplacement, low friction and great mobility. There was also considerable remobilisation of the deposits and secondary flowage after the initial deposition, creating the lobe which was channeled northwards under gravity towards the Monturaqui Basin.

The large volume and stratification of the deposit suggests that the failure was not merely the result, as at Mount St Helens, of slope failure of the volcanic cone. Structural evidence has recently been interpreted to suggest that prior to the failure the weak underlying substrata had been spreading under the load of the volcano. The remnants of thrust anticlines at La Flexura, west of the collapse amphitheatre, delineate the western edge of this spreading zone. The suggestion is that the deforming substrata suffered catastrophic failure as a result of gravitational spreading and was ejected to the northwest on the collapse of the basal anticlines. The substrata then formed the lower horizon of the debris avalanche, upon which the remainder of the edifice was carried and deposited. As a consequence, the large volume, high fluidity and stratification of the deposit can be explained.

Female Water Striders Expose Their Genitalia Only After Males 'Sing'

Chang Seok Han and Piotr Jablonski at Seoul National University, Korea have found that by evolving a morphological shield to protect their genitalia from males' forceful copulatory attempts, females of an Asian species of water strider seem to "win" the evolutionary arms race between the sexes. Instead, females only expose their genitalia for copulation after males produce a courtship "song" by tapping the water surface.

150 years after the publication of Charles Darwin's On the Origin of Species, Han and Jablonski used common insects, water striders, to study the intricacies of evolutionary conflict between males and females. The mechanisms for the way Darwinian natural selection, acting separately on males and females, result in different traits in males than in females (for example, different body sizes to guarantee the highest number of offspring during an individual's lifetime) are already quite well understood.

Sometimes, however, a behavioral trait, such as mating frequency, depends on both the male and the female characteristics. Natural selection favors higher mating frequency in males than in females in many animals, including humans. This leads to an evolutionary "arms race" where males evolve adaptations that force females to mate, while females evolve defenses against males' attempts.

As in the arms races between countries and political powers, it is rare for one sex to "win" in this evolutionary race.

However, in the study by Han and Jablonski, carried out at the Laboratory of Behavioral Ecology and Evolution at Seoul National University, females of an Asian species of water striders, Gerris gracilicornis, do seem to win this race as they have evolved a morphological shield behind which their genitalia are hidden from males, protecting them against the males' forceful attempts to mate.

In an apparent response to the female adaptation, after the violent mounting onto the female's back (typical in water striders), males of this species produce courtship signals by tapping the water surface with their middle legs. It is only after receiving the male's "song" that females expose their genitalia for copulation

Search For ET Just Got Easier: Effective Way To Search Atmospheres Of Planets For Signs Of Life

Astronomers using the Science and Technology Facilities Council's (STFC) William Herschel Telescope (WHT) on La Palma have confirmed an effective way to search the atmospheres of planets for signs of life, vastly improving our chances of finding alien life outside our solar system.

The team from the Instituto de Astrofisica de Canarias (IAC) used the WHT and the Nordic Optical Telescope (NOT) to gather information about the chemical composition of the Earth's atmosphere from sunlight that has passed through it. The research is published June11 in Nature.

When a planet passes in front of its parent star, part of the starlight passes through the planet's atmosphere and contains information about the constituents of the atmosphere, providing vital information about the planet itself. This is called a transmission spectrum and even though astronomers can't use exactly the same method to look at the Earth's atmosphere, they were able to gain a spectrum of our planet by observing light reflected from the Moon towards the Earth during a lunar eclipse. This is the first time the transmission spectrum of the Earth has been measured.

The spectrum not only contained signs of life but these signs were unmistakably strong. It also contained unexpected molecular bands and the signature of the earth ionosphere.

Enric Palle, lead author of the paper, from the Instituto de Astrofisica de Canarias, said, "Now we know what the transmission spectrum of a inhabited planet looks like, we have a much better idea of how to find and recognize Earth like planets outside our solar system where life may be thriving. The information in this spectrum shows us that this is a very effective way to gather information about the biological processes that may be taking place on a planet."

Pilar Montañes-Rodriguez, from the Instituto de Astrofisica de Canarias, added, "Many discoveries of Earth-size planets are expected in the next decades and some will orbit in the habitable zone of their parent stars. Obtaining their atmospheric properties will be highly challenging; the greatest reward will happen when one of those planets shows a spectrum like that of our Earth."

The past two decades have witnessed the discovery of hundreds of exoplanets (planets beyond our solar system). Ambitious missions, ground and space based, are already being planned for the next decades, and the discovery of Earth-like planets is only a matter of time. Once these planets are found, techniques like transmission spectra will be invaluable to their further exploration.

Professor Keith Mason, Chief Executive of the Science and Technology Facilities Council (STFC), said, "This new transmission spectrum is good news for future upcoming ground and space based missions dedicated to the search for life in the Universe. The UK is committed to cutting edge science and UK owned facilities like the WHT are helping to make many groundbreaking discoveries and expand our knowledge of the Universe. Not only do these results improve our knowledge of our own planet but we now have an effective way to search for life on the increasing number of exoplanets being found by astronomers."

The results on the WHT were achieved using LIRIS, a very efficient near-IR imager/spectrograph built and developed at IAC. LIRIS became a common-user instrument at the WHT as a result of the agreement signed by IAC to become a partner at ING in 2003.

Asteroid Probe Set to "Collide" With Earth

A 1,124-pound (510-kilogram) space probe will "collide" with our home planet in June 2010 to simulate an approaching asteroid, Japanese scientists have announced.

The Hayabusa spacecraft is currently on its way back to Earth after a successful mission that landed on and hopefully collected samples from the asteroid Itokawa.Potential samples will be aboard a heat-resistant capsule that will separate from Hayabusa shortly before re-entry into Earth's atmosphere so they can be recovered.

But experts say the main body of the craft will most likely disintegrate during the trip through Earth's atmosphere.

Although the plan was not part of Hayabusa's original mission, scientists at the Japan Aerospace Exploration Agency (JAXA) recently decided to make the most of the doomed probe's return.

"Even though Hayabusa is not actually an asteroid, it will be on a path that will cause it to collide with the Earth in the same way as an asteroid," said JAXA spokesperson Akinori Hashimoto.

"We will monitor its movements, and the data will enable us to accurately predict the future paths of asteroids that are on course to come close to the Earth."

A Better Lookout

While other space agencies have programs for tracking asteroids that might hit Earth, JAXA doesn't yet have the ability to monitor these so-called near-Earth asteroids.

So a team of researchers headed by Makoto Yoshikawa has developed a prototype system to calculate the trajectory, time, speed, and likelihood of an asteroid impact.

In October 2008, the team had a chance to test its system by tracking asteroid 2008 TC3, an incoming space rock about 13 feet (4 meters) wide that astronomers at the Catalina Sky Survey in Arizona had spotted a few hours before it became a fireball in the skies over Sudan.
The system predicted the time the asteroid entered the atmosphere to within 0.5 second and pinpointed the location of its entry to within 8 miles (13 kilometers).

Hayabusa's return to Earth will be even easier to track, the scientists said, because they will have months of advance warning and plenty of information on the craft's exact size and flight path.

The event therefore provides the team with a chance to fine-tune their asteroid-tracking calculations.

"It is very important that we develop accurate ways to predict where asteroids are going to strike, because even small ones can cause a great deal of damage," Hashimoto said.

For example, he noted, a comet or meteorite a mere 197 feet (60 meters) wide is thought to have caused the Tunguska event of 1908.

That blast, which flattened large swaths of Siberian forest, was a thousand times more powerful than the atomic bomb dropped on Hiroshima in 1945.

By contrast, Itokawa is about 984 feet (300 meters) wide. If that rock hit Earth, it would cause an explosion about 150,000 times as powerful as the Hiroshima bomb.

"Pristine" Recovery

The Japanese agency will get international help tracking Hayabusa's re-entry, noted Donald K. Yeomans, manager of NASA's Near-Earth Object Program based in Pasadena, California.

"The entrance of the Hayabusa spacecraft into the Earth's atmosphere will be tracked before entry by ground-based optical telescopes in an effort to verify the software that has recently been developed by JAXA," he said.

In addition, Yeomans said, ground-based telescopes around the world will watch for the sample-return capsule to help ensure its safe recovery.

Any samples from Itokawa would be a huge boon to science, JAXA's Hashimoto said, because they would be the first "pristine" pieces of asteroid ever recovered.

"We are not sure what we will learn until we have had a chance to analyze it," Hashimoto said, "but at the very least it will teach us many things about the makeup of Itokawa."

Searching for Afghanistan's Third Giant Buddha

In Bamiyan, Afghanistan, archaeologist Zemaryalai Tarzi is unearthing and restoring important reminders--like this fourth-century Buddha head--of a more peaceful past.

When the Taliban blew up two colossal Buddha statues in Bamiyan in 2001, nobody was more aggrieved than Tarzi, who had protected them with steel reinforcements in the 1970s as Afghanistan's Director of Archaeology.

Now he is determined to bring Bamiyan's other ancient riches to light. He returned to begin new excavations in 2002, after 23 years in exile. Tarzi is searching for a third giant Buddha--one that's reclining and is believed to stretch 1,000 feet (300 meters) long underground.



The Silk Road traversed central Afghanistan and brought cultural, artistic, and religious influences to the region from ancient Greece, China, Persia, and India. More recently constructed mud fortresses, like the one pictured here, also dot the Bamiyan landscape.

Nearby is Afghanistan's Band-i-Amir national park, the country's first. Could Afghan tourism flourish someday? "While the political climate is discouraging now, the results of my excavations are already promising for when tourism will restart," Tarzi said in spring 2009.


Archaeologist Zemaryalai Tarzi uses a brush to clean the face of a fourth-century Buddhist clay head.

Restoration is a vital aspect of his work, which is supported in part by the National Geographic Society's Expeditions Council. Tarzi and his team of students, archaeologists, and museum restorers have cleaned and restored numerous other Buddhist clay sculptures found in Bamiyan.

Tarzi hopes someday these will fill exhibit cases in Afghan museums, which have suffered from damage and looting.


Ancient Bamiyan was an influential hub of Buddhist learning and practice. Monks and pilgrims traveled there from as far away as China.

Tarzi and his team have unearthed this and various other Buddha heads dating back more than 1,500 years.

"These objects from the past, and the story of the sites they originate from, will become a source of inspiration and help the people of Afghanistan to reconnect with their roots," Tarzi said in spring 2009.



An ancient Buddhist monastic complex uncovered by archaeologist Zemaryalai Tarzi includes these stupas, or places of worship. This is one of several monasteries he's excavated in Bamiyan. Other finds include gold coins, clay statues, even an ancient glass-blowing studio.

"We unearth, protect, and restore," Tarzi said. "Afghanistan today is in a dire crisis. Without having recovered its national identity, it is essential it must seek teaching from its historical and cultural past."



An empty niche (left) remains where a 174-foot (53-meter) Buddha--carved 14 centuries ago into sandstone cliffs and pictured in inset--overlooked Afghanistan's Bamiyan Valley.

In 2001 the Taliban blew it up, along with its 125-foot (38-meter) companion statue, an act that outraged the world. Buddhist monks once lived in the caves that pock the cliff face.

Zemaryalai Tarzi is searching for a third giant Buddha, believed to be buried underground and to extend 1,000 feet (300 meters) reclining.
—Contemporary photograph courtesy Zemaryalai Tarzi; historical inset photograph by Zaheeruddin Abdullah, AP



The feet are all that's left of half a dozen standing Buddhist statues in Bamiyan's Eastern Monastery, excavated by archaeologist Zemaryalai Tarzi.

In 2008, Tarzi and his team uncovered a 62-foot (19-meter) reclining Buddha--much smaller than the 1,000-foot (300-meter) Sleeping Buddha he's determined to find, but still a tantalizing hint of what may await if his quest succeeds.

He's basing his search on a detailed account by a seventh-century Chinese pilgrim who visited the region.


Bamiyan was a hub along the ancient Silk Road, and its art synthesizes diverse roots. This bust unearthed at a Buddhist temple by archaeologist Zemaryalai Tarzi reflects ancient Greek influences, said National Geographic's Fredrik Hiebert, an expert on Afghan antiquities.

Tarzi said his excavations are helping to provide evidence for Bamiyan's key role "in the exchange process of artistic currents between India, China, and Central Asia."


Fortification towers crown a Bamiyan cliffside site surveyed by archaeologist Zemaryalai Tarzi. A 29-foot (9-meter) Buddha stood in the now empty niche (center, bottom) before being destroyed by Taliban.

Here in Bamiyan's Kakrak Valley, Tarzi is surveying a monastery and remnants of a pre-Islamic town (not shown). As the 2009 field season begins, he looks forward to uncovering more layers of Bamiyan's rich history.

Quetzal

The resplendent quetzal is an aptly named bird that many consider among the world's most beautiful. These vibrantly colored animals live in the mountainous, tropical forests of Central America where they eat fruit, insects, lizards, and other small creatures.

During mating season, male quetzals grow twin tail feathers that form an amazing train up to three feet (one meter) long. Females do not have long trains, but they do share the brilliant blue, green, and red coloring of their mates. Male colors tend to be more vibrant.

Resplendent quetzal pairs use their powerful beaks to hollow hole nests in rotted trees or stumps. Inside, they take turns incubating two or three eggs—though males have such long tails that they sometimes stick outside the nest.

Young quetzals can fly at about three weeks of age, but males do not begin to grow their long tail plumes for three years.

Resplendent quetzals are also known as Guatemalan quetzals, and the birds are the symbol of that nation. Guatemala also trades in currency known as the "quetzal".

Unfortunately, these striking birds are threatened in Guatemala and elsewhere throughout their range. They are sometimes trapped for captivity or killed, but their primary threat is the disappearance of their tropical forest homes. In some areas, most notably Costa Rica's cloud forests, protected lands preserve habitat for the birds and provide opportunities for ecotourists and eager bird watchers from around the globe.

Such admirers continue a long history of adoration for the quetzal. The bird was sacred to the ancient Maya and Aztec peoples, and royalty and priests wore its feathers during ceremonies.

Arizona UFO Caught on Film!

By Jenny Williams

I casually walked out to get the mail this evening, slowly walking up the hill, getting there, putting in my key, removing the few items, locking it again. I turn around to walk back down the hill, toward the west and saw the gorgeous dusk sky. “Look, there’s Venus!” I said to myself. “Wait. That is too big to be Venus (or a space station for that matter).” I was puzzled by what I saw, and kept thinking, “That can’t be Venus.”

I got back to the house as quickly as I could, plunked the mail down on the table and got out my telescope. I pointed it in the general direction of the bright light, lined it up properly, and then took a look in the eyepiece. I was completely blown away. I did not expect to see what I saw. It was a ghostly balloon. I wasn’t sure what it was doing there, but I later looked it up. It even made the front page of the online version of our local newspaper, though my photo is a lot better than theirs, believe it or not.

What I saw is the NASA weather balloon that’s made such a fuss in Arizona lately. It is measuring gamma ray emissions. Well, whatever it’s up to, it made my evening a thrilling one.

The New Mercedes

An experimental concept car from Mercedes-Benz turns turns the entire vehicle into an airbag using novel metal panels that inflate moments before impact.

The unimaginatively named ESF 2009 Experimental Safety Vehicle features gadgetry and safety features akin to a moon shot. Chassis components inflate to maximize impact resistance. An airbag under the car slows and supports the vehicle in a crash. Seats protect passengers like eggs in a carton. The list goes on.

“Safety is a central element of the Mercedes-Benz brand,” Dr. Dieter Zetsche, Daimler chairman and Mercedes CEO, said in a statement. “In this respect we have been setting the pace in the market for almost 70 years. The ESF 2009 shows that we still have plenty of ideas and the absolute will to lead the automobile industry in this field even in the future.”

The ESF is just a concept at this point, and it could be years before any of its features appear in showrooms. But the car highlights the efforts automakers are making to build cars that protect us from each other And ourselves.



Volvo, for example, is determined to offer an almost injury-proof car by 2020, an effort Sweden’s head of traffic safety has called the biggest revolution in automaking since the invention of the seat-belt. Automakers are pouring vast sums into research and development into the campaign to increase safety, something Mercedes says is imperative even as the industry takes a beating from the economy.

“Even in economically difficult times, we refuse to make any cuts where innovation is concerned,” said Dr. Thomas Weber, who serves on Daimler’s R&D board.

The ESF 2009, based on the company’s $90,000 S 400 Hybrid, is the first no-holds-barred safety concept car Mercedes has built since 1974, and it highlights some of the company’s best engineering. The two centerpieces of the car are “Pre-Safe” inflating chassis components and the “Braking Bag” under the car.

Pre-safe uses inflatable metal structures within the body to increase impact absorption. Mercedes says they inflate (see diagram below) to 145 to 290 PSI within fractions of a second when on-board sensors detect a crash is imminent.

The braking bag, installed between the front axle and the underbody, works just like the airbag in a steering wheel. When sensors detect an impending crash, the bag inflates, briefly increasing the rate of deceleration to 20 meters per second squared. The bag also raises the car as much as 8 centimeters to minimize brake dive, which occurs when you stomp on the brake. It sounds crazy, but Mercedes says it works.

“Initial trials of the principle have shown this idea to have considerable potential,” Dr. Ing. Rodolfo Schöneburg, the company’s head of safety development, said in a statement. “In the next few years we intend to research and develop this potential further.”

The car features an infrared camera to detect pedestrian, deer and other hazards. Mercedes also introduced something it calls “Interactive Vehicle Communication.” It uses a variety of sensors, cameras and wireless networks to provide real-time information about everything from the weather to local road conditions. Mercedes, which spent seven years working on the system, is by no means alone in developing this technology. Several automakers are working to bring wireless communication into cars, and researchers in Australia have developed cars that can convey such information and “talk” to other vehicles.

Mercedes rolled out a slew of passenger protection features in the ESP 2009, including “belt bags” that combine a seat belt with an airbag and “interseat protection.” That system is essentially a pair of airbags, one up front and one in the rear, between the seats. They inflate in a crash to protect passengers like eggs in a carton. Toyota is working on a similar system.

Other features include an improved version of the Pre-Safe passenger restraint system called Pre-Safe Pulse that moves passengers ever-so-slightly toward the center of the car in a side-impact crash. The “Child Protect” baby seat features padded bolsters that cradle the child’s head in a crash. There’s also a child-cam that let’s you keep an eye on Junior without taking your eyes off the road.

The list goes on and on - the press briefing of the car’s features runs 42 pages - but you get the idea. And Mercedes is nowhere near done.

“We have a wealth of ideas on how safety might be improved still further,” Schöneburg said. “Some of these can be realized within a relatively short time. Other concepts like the inflatable metal sections in PRE-Safe Structure lie well in the future.”

Photos: Mercedes Benz. The main photo shows the display of the Interavtive Vehicle Communications system.

Ocean Acidification: 100 Years in the Future

A study published in an upcoming issue of the journal Current Biology paints a grim picture of the future impact of ocean acidification on marine organisms, reports ENN's Angelique van Engelen. While the study doesn't contribute much that is new in terms of our current understanding of the process -- indeed, the scientists' estimation that seawater pH will drop to 7.7 from a normal 8.1 is well in line with most estimates -- it provides yet more evidence that acidification will devastate many forms of marine life in the near future.

http://www.nas.nasa.gov/About/Education/Ozone/ozonelayer.html

Tripling of seawater acidity expected by 2100

Jon Havenhand and Michael Thorndyke of the University of Gothenburg subjected sea urchins to an environment whose seawater pH had artificially been reduced from 8.1 to 7.7; in other words, its acidity was tripled. They found that the increased acidity significantly lowered the urchins' ability to reproduce -- up to 25% -- by inhibiting the movement of their sperm. For those cases in which fertilization was successful, only 75% of the resultant eggs developed into larvae.

A 25 percent drop in fertility is the equivalent of a 25 percent drop in the reproductive population. It remains to be seen whether other species exhibit the same effect, but, translated to commercially and ecologically important species such as lobsters, crabs, mussels and fish, acidification would have far reaching consequences, said Havenhand.

Assessing the impact of ocean acidification on marine life

Like other marine organisms whose shells or skeletons are made of calcium carbonate (i.e. limestone), sea urchins suffer when the pH drops. The lower pH inhibits these organisms' growth by dissolving their shells and, in more extreme cases, prevents it altogether (see: corals). I wrote about a similar study a few months ago (on World Ocean Day, appropriately enough) which examined the impact of low pH water -- down to 7.4, in some places -- on a variety of organisms, including corals, calcifying algae and sea snails. Not surprisingly, the results were equally discouraging:

"The results were stark: No corals were present, mollusks were seen with their shells dissolving (none were present in area with a pH of 7.4) and calcifying algae (those that form calcium carbonate skeletons) were often displaced by non-calcifying species like seagrasses, which benefited from the extra carbon dioxide. Overall, the number of species present near the vents was 30 percent lower when compared to neighboring areas."

While some may benefit over the short-term, including several species of phytoplankton, the long-term impacts of ocean acidification are unequivocally bad.

http://www.treehugger.com/files/2008/06/future-ocean-acidification.php
http://www.treehugger.com/files/2008/07/noaa-report-corals.php
http://www.treehugger.com/files/2007/11/shellfish_ocean_acidification.php