Chinese Spacecraft Dock in Orbit
|11:14:55 PM, Wednesday, November 02, 2011|
"China has joined two space vehicles together in orbit for the first time.
The unmanned Shenzhou 8 craft, launched earlier this week, made contact with the Tiangong-1 space lab at 1729 GMT. The union occurred over China itself.
Being able to dock two space vehicles together is a necessary capability for China if it wants to start building a space station towards the decade's end.
Although no astronauts were in the Shenzhou craft this time, future missions will carry people.
Tuesday's procedure (Beijing time 0029, Thursday) took place at an altitude of about 340km. It was automated but overseen on the ground at the Beijing Aerospace Flight Control Centre.
The vehicles used radar and optical sensors to compute their proximity to each other and guide their final approach and contact. A video feed from orbit showed the final moments of the vehicles coming together.
Shenzhou 8 was the active craft in the docking. It fired its thrusters to push its front end towards the docking port of Tiangong-1. Once the vehicles' docking rings had made a good capture, 12 hooks were deployed to fix the craft in place. Protruding pins made electrical connections.
From first contact to confirmation of a seal took about 10 minutes.
Shenzhou 8 and Tiangong-1 will spend two weeks circling the globe together before Shenzhou 8 heads back to Earth.
"After a joint flight of about 12 days, they will separate," explained Prof Yang Yuguang from the China Aerospace, Science and Industry Corporation.
"Then the Shenzhou 8 will draw back to about 140m. After that they will perform a second docking. Then they will have a flight of two days. Then they will be separated to about 5km; this will be a safe distance for both vehicles. Then the re-entry procedure will be performed by the Shenzhou 8 spaceship," he told state broadcaster China Central Television (CCTV).
The return capsule will land by parachute to allow experiments carried into orbit to be recovered for analysis. The German space agency (DLR) has supplied an experimental box containing fish, plants, worms, bacteria and even human cancer cells for a series of biological studies.
"This is a great moment for Chinese space activities," observed DLR chairman Prof Jan Woerner.
"This co-operation between China and Germany is called the Simbox; and it's a box in which we have small apparatus to investigate the cells of plants and animals, to see their behaviour under zero gravity conditions.
"It's a really sophisticated experiment and I hope that the results will help also on Earth to learn more about the behaviour of cells in cancer and the immune system...""
New Material for Air Cleaner Filters that Captures Flu Viruses
|11:04:06 PM, Wednesday, November 02, 2011|
"With flu season just around the corner, scientists are reporting development of a new material for the fiber in face masks, air conditioning filters and air cleaning filters that captures influenza viruses before they can get into people's eyes, noses and mouths and cause infection. The report on the fiber appears in ACS' journal Biomacromolecules.
Xuebing Li, Peixing Wu and colleagues explain that in an average year, influenza kills almost 300,000 people and sickens millions more worldwide. The constant emergence of new strains of virus that shrug off vaccines and anti-influenza medications has led to an urgent need for new ways of battling this modern-day scourge. So Li, Wu and colleagues sought a new approach, using a substance termed chitosan made from ground shrimp shells.
The scientists combined chitosan with substances that the flu virus attaches to in order to infect cells. They found that this new version of chitosan ideal for attaching to fibers of face masks and air filters was highly effective in capturing flu virus. The material could become an important addition to vaccinations, anti-influenza medications, and other measures in battling flu, they suggest.
The high transmissibility and genetic variability of the influenza virus have made the design of effective approaches to control the infection particularly challenging. The virus surface hemagglutinin (HA) protein is responsible for the viral attachment to the host cell surface via the binding with its glycoligands, such as sialyllactose (SL), and thereby is an attractive target for antiviral designs. Herein we present the facile construction and development of two SL-incorporated chitosan-based materials, either as a water-soluble polymer or as a functional fiber, to demonstrate their abilities for viral adhesion inhibition and decontamination. The syntheses were accomplished by grafting a lactoside bearing an aldehyde-functionalized aglycone to the amino groups of chitosan or chitosan fiber followed by the enzymatic sialylation with sialyltransferase. The obtained water-soluble SL–chitosan conjugate bound HA with high affinity and inhibited effectively the viral attachment to host erythrocytes. Moreover, the SL-functionalized chitosan fiber efficiently removed the virus from an aqueous medium. The results collectively demonstrate that these potential new materials may function as the virus adsorbents for prevention and control of influenza. Importantly, these materials represent an appealing approach for presenting a protein ligand on a chitosan backbone, which is a versatile molecular platform for biofunctionalization and, thereby, can be used for not only antiviral designs, but also extensive medical development such as diagnosis and drug delivery."
Tiny 'Saber-Toothed Squirrel' Found
|10:50:42 PM, Wednesday, November 02, 2011|
"As suggested in the "Ice Age" movies, some crazy-looking creatures roamed the planet millions of years ago. But there is a large gap in the fossil record from about 60 million to 120 million years ago when it comes to mammals in South America. Where were they, and what did they look like?
Scientists have now discovered a quirky little creature from this time period, as reported in the journal Nature. It's called Cronopio dentiacutus, and it resembles a mouse-sized squirrel with proportionally long teeth, although technically speaking it is neither a squirrel nor saber-toothed.
"The reality of exploration and research can sometimes be as strange as fiction that we see in the movies," said Guillermo Rougier, lead author of the study and professor at the University of Louisville.
The extinct mammal, which lived 94 million years ago, belongs to the lineage that has given rise to the marsupials and placental mammals that we know today. It's related to all living mammals, including humans in a remote way. It has been extinct for about 60 million years. Rougier and colleagues examined its unique skull.
"It was a lot more primitive than we are with regard to the way in which the skull was put together; the teeth were very primitive," Rougier said. "The skull is about an inch long."
Scientists believe was Cronopio dentiacutus was an insectivore, which is common for small animals today. Their teeth seem to be specialized for cutting and crushing; the large canines of Cronopio dentiacutus could puncture through small insects. To give you some perspective on the size of these canines, imagine if one of your front teeth came down below your chin, Rougier said.
Coronpio dentiacutus lived at the same time as small carnivorous dinosaurs, terrestrial crocodiles and snakes with legs. It inhabited the flood plains of Argentina that is now a desert area in Patagonia, where people live on subsistence farming.
Most mammals were very small, like Coronpio dentiacutus, at that time, said Rougier. It wasn't until big dinosaurs went extinct that mammals grew to be as large as cats and small dogs.
"These were the tiny little guys that would squirrel in between the toes of the dinosaurs trying not to get stepped on.""
Fruit Fly Intestine May Hold Secret to the Fountain of Youth
|10:43:08 PM, Wednesday, November 02, 2011|
"One of the few reliable ways to extend an organism's lifespan, be it a fruit fly or a mouse, is to restrict calorie intake. Now, a new study in fruit flies is helping to explain why such minimal diets are linked to longevity and offering clues to the effects of aging on stem cell behavior.
Scientists at the Salk Institute for Biological Studies and their collaborators found that tweaking a gene known as PGC-1, which is also found in human DNA, in the intestinal stem cells of fruit flies delayed the aging of their intestine and extended their lifespan by as much as 50 percent.
"Fruit flies and humans have a lot more in common than most people think," says Leanne Jones, an associate professor in Salk's Laboratory of Genetics and a lead scientist on the project. "There is a tremendous amount of similarity between a human small intestine and the fruit fly intestine."
The findings of the study, which was a collaboration between researchers at the Salk Institute for Biological Studies and the University of California, Los Angeles, were published online in Cell Metabolism.
Scientists have long known that calorie restriction, the practice of limiting daily food intake, can extend the healthy lifespan of a range of animals. In some studies, animals on restricted diets lived more than twice as long on average as those on non-restricted diets.
While little is known about the biological mechanisms underlying this phenomenon, studies have shown that the cells of calorie-restricted animals have greater numbers of energy-generating structures known as mitochondria. In mammals and flies, the PCG-1 gene regulates the number of these cellular power plants, which convert sugars and fats from food into the energy for cellular functions.
This chain of connections between the mitochondria and longevity inspired Jones and her colleague to investigate what happens when the PCG-1 gene is forced into overdrive. To do this, they used genetic engineering techniques to boost the activity of the fruit fly equivalent of the PCG-1 gene. The flies (known as Drosophila melanogaster) have a short lifespan, allowing the scientists to study aging and longevity in ways that aren't as feasible in longer-lived organisms such as mice or human.
The researchers found that boosting the activity of dPGC-1, the fruit fly version of the gene, resulted in greater numbers of mitochondria and more energy-production in flies - the same phenomenon seen in organisms on calorie restricted diets. When the activity of the gene was accelerated in stem and progenitor cells of the intestine, which serve to replenish intestinal tissues, these cellular changes correspond with better health and longer lifespan. The flies lived between 20 and 50 percent longer, depending on the method and extent to which the activity of the gene was altered.
"Their intestines were beautiful," says Christopher L. Koehler, a doctoral-student at University of California San Diego who conducts research in Jones' laboratory. "The flies with the modified gene activity were much more active and robust than the other flies."
Part of the reason for this might be that boosting the fruit fly version of PCG-1 stimulates the stem cells that replenish the intestinal tissues, keeping the flies' intestines healthier. The findings suggest that the fruit fly version of PCG-1 can act as a biological dial for slowing the aging process and might serve as a target for drugs or other therapies to put the breaks on aging and age-related diseases.
"Slowing the aging of a single, important organ - in this case the intestine - could have a dramatic effect on overall health and longevity," Jones says. "In a disease that affects multiple tissues, for instance, you might focus on keeping one organ healthy, and to do that you might be able to utilize PGC-1.""
Video of NYC Fire Brigade in 1893
|2:48:13 AM, Wednesday, November 02, 2011|
"First Ever Video Footage (1893) of New York Fire Brigade. Filmed nearly 120 years ago, this is quite possibly the first ever footage of the New York Fire Brigade. The film is very grainy but it clearly shows firemen rushing through New York on horse drawn engines. Behind them, you can see some sort of electric powered streetcar or trolley system with 'Clinton Avenue' on the back."
‘A Toad-Eat-Toad World,’ and Other Tales of Animal Cannibals
|10:53:35 PM, Tuesday, November 01, 2011|
"When Richard Shine, a biologist at the University of Sydney in Australia, first heard the mystery of the missing eggs, he feared it was another case of what might be called invasive toadkill. He and his colleagues were studying the cane toad, Rhinella marina, a big, warty, sludge-colored Latin American amphibian that was brought to the continent years ago in an ill-fated effort at beetle control.
The researchers already knew that many large Australian carnivores like freshwater crocodiles and marsupial quolls had died after naïvely feasting on the highly toxic adult toads. Now it seemed that smaller predators were going after the toad’s equally poisonous eggs, and Dr. Shine worried that they too would be doomed.
Follow-up field studies soon revealed the identity of the caviar thieves. To the researchers’ astonishment, Dr. Shine said, it was cane toads themselves — or rather their tadpoles, which would swim over to each fresh batch of Rhinella eggs and “desperately consume” every slick black spherelet they could find.
Significantly, the tadpoles weren’t simply hungry for a generic omelette. Reporting in the journal Animal Behaviour, Dr. Shine and his co-workers showed that when given a choice between cane toad eggs and the similar-looking egg masses of other frog species, Rhinella tadpoles overwhelmingly picked the cannibal option. Oh, little cane toads lacking legs, how greedily you snack on pre-toads packed in eggs!
Life after metamorphosis brought scant relief from fraternal threats. The scientists also demonstrated that midsize cane toads wriggle digits on their hind feet to lure younger cane toads, which the bigger toads then swallow whole. “A cane toad’s biggest enemy is another cane toad,” Dr. Shine said. “It’s a toad-eat-toad world out there.”
Rhinella’s brutal appetite is among a string of recent revelations of what might be called extreme or uncanny cannibalism, when one animal’s determination to feed on its fellows takes such a florid or subversive turn that scientists are left, as Mark Wilkinson of the Natural History Museum in London put it, “gobsmacked” by the sight.
There are males that demand to be cannibalized by their lovers and males that seek to avoid that fate by stopping midcourtship and hammily feigning rigor mortis. There are mother monkeys that act like hipster zombies, greeting unwanted offspring with a ghoulish demand for brains; and there are infant caecilians — limbless, soil-dwelling amphibians — that grow fat by repeatedly skinning their mother alive.
In the past, animal cannibalism was considered accidental or pathological: Walk in on a mother rabbit giving birth, and the shock will prod her to eat her bunnies. Now scientists realize that cannibalism can sometimes make good evolutionary sense, and for each new example they seek to trace the selective forces behind it.
Why do cane toad tadpoles cannibalize eggs? Researchers propose three motives. The practice speeds up maturation; it eliminates future rivals who, given a mother toad’s reproductive cycle, are almost certainly unrelated to you; and it means exploiting an abundant resource that others find toxic but to which you are immune.
“We’re talking about a tropical animal that was relocated to one of the driest places on earth,” Dr. Shine said. “Cannibalism is one of those clever tricks that makes it such a superb colonizer and a survival machine.”
Maydianne Andrade, a biologist at the University of Toronto Scarborough in Ontario, has studied the redback spider, a type of black widow in which males willingly fling themselves onto the fangs of their much bigger mates. Dr. Andrade has found that the self-sacrificial act is simply the grand finale of an elaborate Ringling Brothers courtship performance that can last hours..."
A Mind Dismembered: In Search of the Magical Penis Thieves
|10:34:54 PM, Tuesday, November 01, 2011|
"No one is entirely sure when magical penis loss first came to Africa. One early incident was recounted by Dr. Sunday Ilechukwu, a psychiatrist, in a letter some years ago to the Transcultural Psychiatric Review. In 1975, while posted in Kaduna, in the north of Nigeria, Dr. Ilechukwu was sitting in his office when a policeman escorted in two men and asked for a medical assessment. One of the men had accused the other of making his penis disappear. This had caused a major disturbance in the street. As Ilechukwu tells it, the victim stared straight ahead during the examination, after which the doctor pronounced him normal. “Exclaiming,” Ilechukwu wrote, “the patient looked down at his groin for the first time, suggesting that the genitals had just reappeared.”
According to Ilechukwu, an epidemic of penis theft swept Nigeria between 1975 and 1977. Then there seemed to be a lull until 1990, when the stealing resurged. “Men could be seen in the streets of Lagos holding on to their genitalia either openly or discreetly with their hand in their pockets,” Ilechukwu wrote. “Women were also seen holding on to their breasts directly or discreetly, by crossing the hands across the chest. . . . Vigilance and anticipatory aggression were thought to be good prophylaxes. This led to further breakdown of law and order.” In a typical incident, someone would suddenly yell: Thief! My genitals are gone! Then a culprit would be identified, apprehended, and, often, killed.
During the past decade and a half, the thievery seems not to have abated. In April 2001, mobs in Nigeria lynched at least twelve suspected penis thieves. In November of that same year, there were at least five similar deaths in neighboring Benin. One survey counted fifty-six “separate cases of genital shrinking, disappearance, and snatching” in West Africa between 1997 and 2003, with at least thirty-six suspected penis thieves killed at the hands of angry mobs during that period. These incidents have been reported in local newspapers but are little known outside the region.
For years I followed this trend from afar. I had lived in East Africa, in Italy, in Thailand, and other places too, absorbing their languages, their histories, their minutiae. I had tried to piece together what it might be like not just to live in those places but really to be in them, to jump in and sink all the way to the bottom of the pool. But through these sporadic news stories, I was forced to contemplate a land more foreign than any I had ever seen, a place where one’s penis could be magically blinked away. I wanted to see for myself, but no magazine would send me. It was too much money, too far, and too strange. Finally, when my wife became pregnant, I realized that it might be my one last reckless chance to go, and so I shouldered the expenses myself and went.
On my first morning in the Mainland Hotel, a run-down place with falling ceiling tiles and broken locks, I awoke to a din, and I realized it was simply the city: the clatter of the 17 million people of Lagos. It was louder than any metropolis I had ever heard. My windows were closed, but it sounded as if they were wide open. For the next few days, I wandered around the city not quite sure where to begin. I went to bookstores and took motorcycle taxis and asked people I met, friends of friends, but without much insight or luck.
Eventually I found my way to Jankara Market, a collection of cramped stands under a patchwork of corrugated-tin sheets that protect the proffered branches, leaves, seeds, shells, skins, bones, skulls, and dead lizards and toads from the elements. All these items are held to contain properties that heal, help, or harm, depending on what one needs them to do. The market is better known for the even darker things one can buy. At Jankara, one can buy juju: magic. On my first trip to Jankara, to look around, I met a woman who loved me, she said, and wanted to marry me. When I told her I was already married, she threatened to bind me to her magically with two wooden figures so that I would not sleep at night until I saw her. But she said it with a glint in her eye, so I didn’t worry.
A few days later, I returned to Jankara to ask her some questions. As soon as I walked into the dark, covered grounds of the market, she saw me..."
A Better Rationale for Science Literacy
|9:58:22 PM, Tuesday, November 01, 2011|
"Current programs sponsored by science foundations such as the American Association for the Advancement of Science emphasize the importance of "science literacy" in both K-12 and higher education. College curricula have pursued these goals through science-literacy requirements or specialized science courses for nonscience majors. Much has been written about what science literacy is, with varying emphasis between the process of science and the knowledge generated by that process.
That's all well and good, but relatively little attention has been spent on why we think science literacy is so important. Statements on the subject often begin with perfunctory justification; the value of science literacy is treated as self-obvious. And "literacy" sounds a bit defensive, laboring to justify the importance of science by defining it in terms of an essential fluency. We don't talk about "philosophical literacy." It seems as if we are straining to justify ourselves in response to religious fundamentalists and postmodernists who seek to constrain or diminish science education.
If science education is important for all Americans, then we need persuasive justifications for emphasizing science for all students in college curricula. I think the most common rationales are not terribly successful. One is that Americans' scores on science-literacy surveys are poor in comparison with other developed nations. That is certainly cause for alarm, but it is not unique to science. Surveys of basic knowledge about history, for example, show similar results. I'm sure that Americans, over all, don't have a good working knowledge of music, either. In general, we are more ignorant than we should be, but that doesn't suggest why we should be fluent in the language and theory of science in particular.
Another common justification for promoting science literacy holds that basic scientific knowledge is an imperative to be able to function in an increasingly technological society. Citizens need scientific knowledge to make better decisions in their lives. But that justification is unsatisfying, because it conflates science and technology and leads to the conclusion that knowledge of science is simply a practical matter. Surveys have shown that Americans have a poor understanding of why there are seasons. Should we teach every American about orbital mechanics? That knowledge wouldn't change the nature of the seasons or when people decide to put on a heavier coat. Likewise, the relationship between matter and energy isn't immediately useful unless you are building a nuclear reactor. The practical-knowledge argument is a trap.
Many have argued that investment in science education makes economic sense. That is a major theme in the work of Thomas Friedman, of The New York Times. The central argument is persuasive: Demand for technically skilled workers is increasing, and American education is not supporting that demand. But, again, this tends to conflate science and technology, and emphasizes the practical over the theoretical. It also marries science to the economic machine in a way that may not be entirely desirable. When certain areas of inquiry no longer lead to obvious profit, they could, under this line of reasoning, be abandoned. And some forms of technological economic growth may actually be in tension with some of the major themes in environmental science..."
Goryachiy Shokolad - Beregi
|9:48:03 PM, Tuesday, November 01, 2011|
Boeing Willing to Let Japan Develop New Deriviative of F/A-18
|4:13:55 AM, Friday, October 28, 2011|
"Boeing, which is proposing the F/A-18E/F for Japan's forthcoming FX fighter competition, would be willing to let the nation develop its manufacturing capability through the joint development of a new derivative of the Super Hornet.
If Japan wanted to further develop the Super Hornet, by coming up with a new derivative, then Boeing would respond positively, says Defense, Space and Security vice-president for international business development Mark Kronenberg.
"We would want to come up with a package that helps them with their aspirations," he adds.
Japan has yet to issue a request for proposals for the FX competition, but plans to buy 40-50 fighters to replace some of its McDonnell Douglas F-4s.
In the early 1990s, Lockheed Martin worked with Japanese industry to develop the Mitsubishi F-2, a derivative of its F-16, but US law-makers at the time blocked it from transferring some technology.
But Kronenberg says technology transfer, with regards to Japan, is less of an issue today.
In the 1980s and early 1990s, Japan seemed to be "20ft tall", because the country's corporations were buying so many businesses overseas, but times have changed and US law-makers are now less wary of it, he says.
When asked if it is feasible to manufacture 40-50 fighters in Japan under licence, Kronenberg says: "It depends on how much you want to pay to get that new manufacturing capability. I think Japan is willing to pay." He adds that Tokyo's long-term objective is to have the technological and manufacturing capability to develop its own fighter.
Some industry observers predict that whichever company wins the FX competition is also likely to win in a subsequent FXX requirement. This is likely to seek over 100 fighters to replace some of Japan's older Boeing F-15s.
In a separate development, Japan's nearest neighbour South Korea announced in January that it is studying whether to develop an indigenous fighter.
Its government says that if it decides to proceed, completion of the first aircraft would be in 2021.
Boeing would also be interested in assisting Seoul with its KFX indigenous fighter programme "if it was part of a long-term path", says Kronenberg.
"We would rather partner in significant markets like Korea rather than compete," he says.
Maybe longer-term some F-15SE technology could be applied, he adds. The South Korean already operates F-15Ks."
Astronomers Discover Complex Organic Matter in the Universe
|3:44:42 AM, Friday, October 28, 2011|
"In today's issue of the journal Nature, astronomers report that organic compounds of unexpected complexity exist throughout the Universe. The results suggest that complex organic compounds are not the sole domain of life but can be made naturally by stars.
Prof. Sun Kwok and Dr. Yong Zhang of the University of Hong Kong show that an organic substance commonly found throughout the Universe contains a mixture of aromatic (ring-like) and aliphatic (chain-like) components. The compounds are so complex that their chemical structures resemble those of coal and petroleum. Since coal and oil are remnants of ancient life, this type of organic matter was thought to arise only from living organisms. The team's discovery suggests that complex organic compounds can be synthesized in space even when no life forms are present.
The researchers investigated an unsolved phenomenon: a set of infrared emissions detected in stars, interstellar space, and galaxies. These spectral signatures are known as "Unidentified Infrared Emission features". For over two decades, the most commonly accepted theory on the origin of these signatures has been that they come from simple organic molecules made of carbon and hydrogen atoms, called polycyclic aromatic hydrocarbon (PAH) molecules. From observations taken by the Infrared Space Observatory and the Spitzer Space Telescope, Kwok and Zhang showed that the astronomical spectra have features that cannot be explained by PAH molecules. Instead, the team proposes that the substances generating these infrared emissions have chemical structures that are much more complex. By analyzing spectra of star dust formed in exploding stars called novae, they show that stars are making these complex organic compounds on extremely short time scales of weeks.
Not only are stars producing this complex organic matter, they are also ejecting it into the general interstellar space, the region between stars. The work supports an earlier idea proposed by Kwok that old stars are molecular factories capable of manufacturing organic compounds. "Our work has shown that stars have no problem making complex organic compounds under near-vacuum conditions," says Kwok. "Theoretically, this is impossible, but observationally we can see it happening."
Most interestingly, this organic star dust is similar in structure to complex organic compounds found in meteorites. Since meteorites are remnants of the early Solar System, the findings raise the possibility that stars enriched the early Solar System with organic compounds. The early Earth was subjected to severe bombardments by comets and asteroids, which potentially could have carried organic star dust. Whether these delivered organic compounds played any role in the development of life on Earth remains an open question."
|3:39:00 AM, Friday, October 28, 2011|
"What new architecture matters now? AD surveyed recently completed projects from around the globe and selected 15 that are not only pushing the boundaries of design and technology but are also shaping up to be some of the most influential structures of the decade..."
US's Most Powerful Nuclear Bomb Being Dismantled
|3:32:15 AM, Friday, October 28, 2011|
"AMARILLO, Texas (AP) — The last of the nation's most powerful nuclear bombs — a weapon hundreds of times stronger than the bomb dropped on Hiroshima — is being disassembled nearly half a century after it was put into service at the height of the Cold War.
The final components of the B53 bomb will be broken down Tuesday at the Pantex Plant near Amarillo, the nation's only nuclear weapons assembly and disassembly facility. The completion of the dismantling program is a year ahead of schedule, according to the U.S. Department of Energy's National Nuclear Security Administration, and aligns with President Barack Obama's goal of reducing the number of nuclear weapons.
Thomas D'Agostino, the nuclear administration's chief, called the bomb's elimination a "significant milestone."
Put into service in 1962, when Cold War tensions peaked during the Cuban Missile Crisis, the B53 weighed 10,000 pounds and was the size of a minivan. According to the American Federation of Scientists, it was 600 times more powerful than the atomic bomb dropped on Hiroshima, Japan, killing as many as 140,000 people and helping end World War II.
The B53 was designed to destroy facilities deep underground, and it was carried by B-52 bombers.
With its destruction, the next largest bomb in operation will be the B83, said Hans Kristensen, a spokesman for the Federation of American Scientists. It's 1.2 megatons, while the B53 was 9 megatons.
The B53's disassembly ends the era of big megaton bombs, he said. The bombs' size helped compensate for their lack of accuracy. Today's bombs are smaller but more precise, reducing the amount of collateral damage, Kristensen said.
Since the B53 was made using older technology by engineers who have since retired or died, developing a disassembly process took time. Engineers had to develop complex tools and new procedures to ensure safety.
"We knew going in that this was going to be a challenging project, and we put together an outstanding team with all of our partners to develop a way to achieve this objective safely and efficiently," said John Woolery, the plant's general manager.
Many of the B53s were disassembled in the 1980s, but a significant number remained in the U.S. arsenal until they were retired from the stockpile in 1997. Pantex spokesman Greg Cunningham said he couldn't comment on how many of the bombs have been disassembled at the Texas plant.
The weapon is considered dismantled when the roughly 300 pounds of high explosives inside are separated from the special nuclear material, known as the pit. The uranium pits from bombs dismantled at Pantex will be stored on an interim basis at the plant, Cunningham said.
The non-nuclear material and components are then processed, which includes sanitizing, recycling and disposal, the National Nuclear Security Administration said last fall when it announced the Texas plant's role in the B53 dismantling.The plant will play a large role in similar projects as older weapons are retired from the U.S.'s nuclear arsenal."
An Infant Star System With 'Thousands of Oceans' Worth of Water
|3:26:21 AM, Friday, October 28, 2011|
"Astrophysicists have detected the first signs of cold water vapor in the outer reaches of a baby star system. The discovery, announced today in Science, not only fills a gap in the convoluted question of how planets form, but also hints where the water that covers Earth-like planets is stored until the rocky bodies can receive and hold onto it as oceans.
The short version of how scientists believe the Earth formed goes like this: Roughly 4.5 billion years ago, the solar system was a spinning disk of gas and dust that looked something like a record, and one groove in that record collapsed into a molten orb that became our planet. About 700 million years later, when Earth was crusty and dried-out, comets, asteroids and other watery space wanderers bombarded the world. In just tens or hundreds of thousands of years, these impacts deposited our life-giving water.
The question is where all that water came from. For decades, astrophysicists have suspected that the water in these small icy bodies originated in the center of the freezing-cold outer zone of planet-forming disks. Yet the water’s temperature—just above absolute zero—made it virtually impossible to detect, preventing scientists from confirming their suspicion.
But now a team of researchers has seen the signs. Using the Herschel Space Observatory, scientists have spied faint signature of water on the surface of an expansive and chilly region of a planet-forming disk spinning around the star TW Hydrae. The extremely faint finding is probably the tip of a colossal celestial iceberg, as a store of water amounting to thousands of Earth oceans probably hides in the center of the disk.
"We now have a glimpse at a very early stage in planetary systems we had only hypothesized to exist," says space scientist Diane Wooden of NASA Ames Research Center, who was not involved in the study. "This has been an extremely difficult signature to find."
The Search for Ice
TW Hydrae, located 175 light-years away from Earth, is between 5 million and 10 million years old. Compared with the 4.5-billion-year-old sun of ours, it’s practically an infant. The star is so young and so close to Earth that scientists look to it for a picture of what our own solar system looked like in its early years. Most captivating of all is TW Hydrae’s spinning disk of gas, dust, water and other planet-building materials; it stretches 200 astronomical units (AU) from the star (one AU is the sun-to-Earth distance). By comparison, the dwarf planet Pluto at its farthest orbital distance is only 49 AU from the sun.
But it’s not easy to find ice, even around a well-studied star. Water is easier to find when it’s hot, because water vapor emits strong signals that instruments called spectrometers can detect. TW Hydrae is hot enough to thaw the ice in the part of its planet-forming disk that’s within three to five AU, so astronomers can see that easily. However, beyond TW Hydrae’s three to five AU border, called the snow line, the signal fades because water freezes. Scientists who’d looked at the TW Hydrae system before couldn’t detect that distant ice, and estimate how much of it might be around to form comets later in the star system’s life.
In May 2009, astronomers got a new tool when the European Space Agency (ESA) launched the Herschel Space Observatory, an orbiting telescope designed to pick up the faintest signals from the coldest objects in space. The team behind this study, led by astrophysicist Michiel Hogerheijde of Leiden University in the Netherlands, pointed Herschel at TW Hydrae and opened the shutter for 18 hours.
"Before Herschel, this was simply not feasible. You have to get outside Earth’s atmosphere to see the water, so you go to space," Hogerheijde says. "The other space telescopes were not sensitive enough."
Although TW Hydrae’s disk is extremely cold beyond 100 AU (just 20 degrees above absolute zero), a weak influx of ultraviolet and X-ray light both from TW Hydrae and nearby stars can form fleeting water vapor molecules. When a molecule of water ice absorbs one of these wavelengths’ photons, the molecule’s two hydrogen and one oxygen atoms split into one hydrogen and one oxygen-hydrogen molecule. They quickly recombine, but Herschel can see the faint infrared radiation they emit (if it stares long enough, that is).
"It’s like when you put an aluminum ball in the microwave. The microwave beam liberates electrons from the aluminum, which we see as sparks," Hogerheijde says.
To the team’s surprise, the cold water vapor signal was three to five times weaker than expected. Yet by comparing the result to a laboratory benchmark, they estimated the icy grains deep inside the disk harbor as much water as 6500 Earth oceans..."
First Google.org-Funded Geothermal Mapping Report Confirms Vast Coast-To-Coast Clean Energy Source
|9:46:10 PM, Tuesday, October 25, 2011|
"New research from SMU's Geothermal Laboratory, funded by a grant from Google.org, documents significant geothermal resources across the United States capable of producing more than three million megawatts of green power – 10 times the installed capacity of coal power plants today.
Sophisticated mapping produced from the research, viewable via Google Earth at http://www.google.org/egs/, demonstrates that vast reserves of this green, renewable source of power generated from the Earth's heat are realistically accessible using current technology.
The results of the new research, from SMU Hamilton Professor of Geophysics David Blackwell and Geothermal Lab Coordinator Maria Richards, confirm and refine locations for resources capable of supporting large-scale commercial geothermal energy production under a wide range of geologic conditions, including significant areas in the eastern two-thirds of the United States. The estimated amounts and locations of heat stored in the Earth's crust included in this study are based on nearly 35,000 data sites – approximately twice the number used for Blackwell and Richards' 2004 Geothermal Map of North America, leading to improved detail and contouring at a regional level.
Based on the additional data, primarily drawn from oil and gas drilling, larger local variations can be seen in temperatures at depth, highlighting more detail for potential power sites than was previously evident in the eastern portion of the U.S. For example, eastern West Virginia has been identified as part of a larger Appalachian trend of higher heat flow and temperature.
Conventional U.S. geothermal production has been restricted largely to the western third of the country in geographically unique and tectonically active locations. For instance, The Geysers Field north of San Francisco is home to more than a dozen large power plants that have been tapping naturally occurring steam reservoirs to produce electricity for more than 40 years.
However, newer technologies and drilling methods can now be used to develop resources in a wider range of geologic conditions, allowing reliable production of clean energy at temperatures as low as 100˚C (212˚F) – and in regions not previously considered suitable for geothermal energy production. Preliminary data released from the SMU study in October 2010 revealed the existence of a geothermal resource under the state of West Virginia equivalent to the state's existing (primarily coal-based) power supply.
"Once again, SMU continues its pioneering work in demonstrating the tremendous potential of geothermal resources," said Karl Gawell, executive director of the Geothermal Energy Association. "Both Google and the SMU researchers are fundamentally changing the way we look at how we can use the heat of the Earth to meet our energy needs, and by doing so are making significant contributions to enhancing our national security and environmental quality."
"This assessment of geothermal potential will only improve with time," said Blackwell. "Our study assumes that we tap only a small fraction of the available stored heat in the Earth's crust, and our capabilities to capture that heat are expected to grow substantially as we improve upon the energy conversion and exploitation factors through technological advances and improved techniques."
Blackwell is scheduled to release a paper with details of the results of the research to the Geothermal Resources Council in October 2011.
Blackwell and Richards first produced the 2004 Geothermal Map of North America using oil and gas industry data from the central U.S. Blackwell and the 2004 map played a significant role in a 2006 Future of Geothermal Energy study sponsored by the U.S. Department of Energy that concluded geothermal energy had the potential to supply a substantial portion of the future U.S. electricity needs, likely at competitive prices and with minimal environmental impact. SMU's 2004 map has been the national standard for evaluating heat flow, temperature and thermal conductivity for potential geothermal energy projects.
In this newest SMU estimate of resource potential, researchers used additional temperature data and in-depth geological analysis for the resulting heat flow maps to create the updated temperature-at-depth maps from 3.5 kilometers to 9.5 kilometers (11,500 to 31,000 feet). This update revealed that some conditions in the eastern two-thirds of the U.S. are actually hotter than some areas in the western portion of the country, an area long-recognized for heat-producing tectonic activity. In determining the potential for geothermal production, the new SMU study considers the practical considerations of drilling, and limits the analysis to the heat available in the top 6.5 km (21,500 ft.) of crust for predicting megawatts of available power. This approach incorporates a newly proposed international standard for estimating geothermal resource potential that considers added practical limitations of development, such as the inaccessibility of large urban areas and national parks. Known as the 'technical potential' value, it assumes producers tap only 14 percent of the 'theoretical potential' of stored geothermal heat in the U.S., using currently available technology...
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