Tuesday, December 30, 2008
That's no moon... that's a fully opera - No, wait, it is a moon. Ganymede, in fact, as captured disappearing behind Jupiter by the Hubble Telescope. Click through for video.
Although the images and movie - made from 540 stills taken over a two hour period - were only released just before Christmas, they were actually shot in April 2007. The reason for the delay in their release? We're saying that it's got something to do with the amount of time the NASA animators were distracted watching Wall-E.Original here
They might have the right stuff, but astronauts are only human. And superstition, sentimentality and the need to commemorate key events affect them just like anybody else. But unlike the rest of us, these folks have the ability to make cosmic gestures with the stuff of everyday life.
What kind of stuff? Some is fairly ordinary before it leaves the grip of Earth's gravity - think stamps and coins - and some is already extraordinary. Some wreckage from the world's worst terrorist incident is now sitting on Mars, for example. And when two bicycle mechanics lofted the world's first manned, powered aeroplane off a windy beach in 1903 they could not have conceived that one day parts of their flying machine would soar through the void, land safely on the Moon - and then fly 385,000 kilometres back to Earth. (You might even say the astronauts who did that had the Wright stuff. Sorry.)
Click through our gallery to see some of the objects that have flown to the final frontier.
MOSCOW (AP) -- American and Russian crewmen installed a probe Tuesday aimed at tracking down problems with a Russian module attached to the international space station and conducted an array of other maintenance and scientific work during a six-hour spacewalk.
But in a setback toward the end of the Russian-controlled mission, American Michael Fincke, the station's commander, and Russian Yury Lonchakov had to remove a device they had just installed because of data transmission problems.
A NASA video feed showed Fincke and Lonchakov in their Russian-built space suits leaving the station from a hatch on its docking compartment 200 miles above the Earth.
''OK, going out into space again,'' Fincke said in Russian. ''It's good to be here again.'' The comments were audible on the NASA feed carried on the Internet.
Russian scientists hope data from the probe installed by Fincke will help explain malfunctions that have repeatedly occurred as the Russian module has attempted to separate from the space station.
Russia's Soyuz module entered the Earth's atmosphere too steeply in separate descents after detaching from the station in October 2007 and April this year, leading to faster- and bumpier-than-usual falls for the crews.
Investigators believe the Soyuz capsule detached too late because a so-called pyrobolt -- an exploding connector that keeps the module fixed to the space station -- failed to detonate on time.
Much of the spacewalk was devoted to arranging connectors and cables for various probes and experiments, and ensuring the reliability of telemetry from the data-gathering equipment.
Fincke and Lonchakov discovered a problem with the data transmission of a device they installed on a small platform outside the station's Zvezda module. The European Space Agency experiment was supposed to gather data on the effects of the space environment on a variety of materials.
''I think we have done all we can. Why isn't it working?'' Lonchakov said after reconnecting the cables several times. They disassembled the experiment to take it back inside the station.
They successfully placed another device on the same platform to measure the plasma environment around the station. The pair also removed a biological experiment known as Biorisk 2.
Fincke and Lonchakov attached cables and performed other tasks as the sun periodically rose and set on the cosmic construction site. They joked with each other early in the spacewalk and appeared to be in a relaxed mood.
''Misha, look this way, I'm taking a picture of you,'' Lonchakov said.
''You are like paparazzi,'' Fincke said.
It was Fincke's fifth spacewalk, Lonchakov's first and the 119th spacewalk conducted from the international space station.U.S. Flight Engineer Sandra Magnus, the third member of the station's Expedition 18, was inside the station helping coordinate the mission with centers in Houston and in Korolyov, Russia, just outside of Moscow.
Researchers from the Pardee Rand Graduate School in Santa Monica researched the relationship between proximity to alcohol retailers in zones around homes in California and drinking in children ages 12 to 17. They found an association among homes within walking distance (about half a mile) of places selling alcohol and evidence of binge drinking and driving after drinking.
The study, published online this month in the American Journal of Public Health, also noted that alcohol is more readily available in minority and lower-income areas. In predominantly white neighborhoods, within a half-mile there are an average 5.5 locations with active alcohol licenses. In predominantly African American neighborhoods it's 6.4 locations; in predominantly Latino, 8.6; and in predominantly Asian, 9.5. Researchers point out that living in areas with higher alcohol sales could also mean more exposure to violent crime and drunk driving.
"Our study suggests that living in close proximity to alcohol outlets is a risk factor for youth," write the authors. "In California, retail licenses are not typically approved within 100 feet of a residence or within 600 feet of schools, public playgrounds and nonprofit youth facilities, but proximity by itself is not sufficient to deny a license. . . . More attention on the proximity rule is needed and environmental interventions need to curb opportunities for youth to get alcohol from commercial sources."
For some, whale watching is a tourist activity. For Gunter Pauli, it is a source of technological inspiration.
"I see a whale, I see a six-to-12-volt electric generator that is able to pump 1,000 liters per pulse through more than 108 miles of veins and arteries," he said. The intricate wiring of the whale's heart is being studied as a model for a device called a nanoscale atrioventricular bridge, which will undergo animal testing next year and could replace pacemakers for the millions of people whose diseased hearts need help to beat steadily.
Pauli -- who directs the Zero Emissions Research and Initiatives (ZERI) Foundation in Geneva -- is an unabashed promoter of biomimicry, the science of making technological and commercial advances by copying natural processes. At a time when many are looking for a way to protect Earth's biodiversity and reduce the ecological impact of industrial products and processes, a growing number of business leaders and environmental activists alike are looking to biomimicry as a way to achieve both ends.
"The idea behind biomimicry is that life has already solved the challenges that we're trying to solve," said Janine Benyus, who leads the Biomimicry Guild, a Helena, Mont.-based consulting group. "There are literally as many ideas as there are organisms."
In the past few years, entrepreneurs have developed and started marketing an array of inventions that imitate natural phenomena. For instance, the resurrection plant, a desert species common in Africa and Latin America, dries up and appears to be dead when water is scarce. It does so without breaking its cells' membranes, enabling it to revive when moisture returns. Researchers have learned to make some vaccines with a similar capability so they do not have to be refrigerated. Other inventors are developing friction-free surfaces modeled on the slippery skin of the Arabian Peninsula's sandfish lizard, an advance that could eliminate the use of ball bearings in many products as well as industrial diamond dust in automobile air bags.
Knowing that the pearl oyster uses carbon dioxide to construct its calcium carbonate shell, a Canada-based company called CO2 Solution developed and patented a technology that converts carbon dioxide emissions into a water-based solution of bicarbonate ions, which can be turned into pure carbon dioxide gas or solid calcium carbonate. The firm has applied the process to cement production, reducing the large amounts of CO2 that process releases.
Oysters "see carbon dioxide as a building material," Benyus said.
The United Nations Environment Program and the International Union for Conservation of Nature have joined the Biomimicry Guild and ZERI to develop a list of Nature's 100 Best -- the most prominent innovations inspired by natural processes.
UNEP Executive Director Achim Steiner said such technologies will be essential to more sustainable development in light of global warming.
"There is simply a transformational challenge . . . that needs new ideas and new solutions to unlock the potential of nature and reinforce the planet's natural carbon storage capacity," he said. "If you can have 7.8 billion people living comfortably with one-tenth, one-thousandth of the amount of energy, that opens up a new realm of possibility."
Some biomimicry products are still in the pipeline, but Steiner said many are in commercial use. "We're not talking about theory anymore," he said. "This is real stuff happening in the real world, in the real market."
Architecture has made the greatest use of biomimicry products. Benyus estimated that 300,000 buildings in Europe boast self-cleaning glass that copies the way water balls up on lotus leaves and simply rolls off.
Biomimicry is also gaining traction as researchers seek to cut the costs of solar cells and make them less rigid. Two companies -- Konarka Technologies in Lowell, Mass., and Dyesol in New South Wales, Australia -- have developed thin, dye-sensitized solar cells that operate on the same principle that plants use to absorb the sun's rays and convert them to energy. These cells are not as efficient as their photovoltaic counterparts, but they are 60 percent cheaper and more flexible.
Including architectural projects, Pauli said, the 100 largest biomimicry products have generated more than $1.5 billion over the past four years. "The market potential is vast," he said.
Other entrepreneurs are experimenting with genetic engineering to create products, such as putting the genes from a spider into a cloned goat to produce a particularly strong form of silk, but Benyus draws a distinction between that sort of invention and her line of work.
"That's not biomimicry," she said. "That's bio-assisted technology."
The payoffs from biomimicry research, she said, provide a strong incentive for conserving plants and animals rather than exploiting nature in destructive ways. "Preserving their habitats is really preserving the wellspring of ideas for the next industrial revolution, that gets us there with the minimum amount of energy, the minimum amount of toxins," she said.
That line of argument encourages environmentalists such as Patrick Ramage, director of the global whale program at the International Fund for Animal Welfare. If inventors can model pacemakers on whales' circulation or wind turbine blades on the flipper of a humpback whale, he said, that will bolster efforts to protect the animals.
Ramage said that humans are grappling with questions such as "What can we learn from these masterpieces of nature? What secrets do they hold that can help us build a better world for ourselves and for them, for animals and people? In the end, our fates and futures as humans and wild animals are not separate; they are inextricably linked."
The end of 2008 brings some discouraging news about our kids' brains and brawn. Recent results from an international math and science test show United States students are performing near the middle of the pack compared to other countries, while their levels of obesity continue to climb.
Historically, these two trends were studied independently with plans of action developed for each. However, several researchers and a new book have been making the case for linking these two problems by showing the effects of aerobic exercise not only on a student's fitness level but also on their test scores.
Earlier this month, the latest (2007) TIMSS (Trends in International Mathematics and Science Study) scores were released. They compare fourth grade students from 36 countries and eighth grade students from 48 countries. They were tested on subjects that were common to all of the countries, including algebra, geometry, chemistry and physics. Overall, 425,000 students participated in the test, which is administered every four years.
In math, American fourth graders came in at 11th place of the 36 countries while eighth graders scored ninth out of 48. Hong Kong and Taiwan ranked first for fourth grade and eighth grade, respectively. In science, Singapore topped the list for both fourth grade and eighth grade, with U.S. science students taking eighth place and 11th place.
While the American math scores have improved slightly, the science scores have dropped. In 2003, U.S. fourth graders were in sixth place in the world and eighth graders were in ninth place. Only 6 percent of U.S. eighth-grade students reached the TIMSS "advanced" level in math, compared to 45 percent of students in Chinese Taipei, 40 percent in Korea, 40 percent in Singapore, 31 percent in Hong Kong, 26 percent in Japan and 10 percent in Hungary.
Regarding student fitness, the most recent figures from the Centers for Disease Control and Prevention report that the percentage of overweight or obese 6- to 11-year-olds has tripled since 1980, with more than 125 million children at unhealthy levels.
Ironically, one of the solutions proposed for raising test scores, the federal No Child Left Behind program, encourages schools to focus more of the school day on the core academic subjects while reducing class time in peripheral subjects, like art, music, and physical education. In fact, only 6 percent of American high schools offer a daily gym class. Yet a 2002 Virginia Tech study showed no relationship between reduced class time in those subjects and higher overall standardized tests.
In his latest book, "Spark: The Revolutionary New Science of Exercise and the Brain" (2008, Little, Brown), John Ratey, a Harvard clinical associate professor of psychiatry, argues for more physical fitness for students as a cure for not only their obesity but also their academic performance.
"I cannot underestimate how important regular exercise is in improving the function and performance of the brain." Ratey writes. "Exercise stimulates our gray matter to produce Miracle-Gro for the brain." That "Miracle-Gro" is a brain chemical called brain-derived neurotropic factor, or BDNF. When we exercise, our working muscles send chemicals into our bloodstream, including a protein known as IGF-1.
Once in the brain, IGF-1 orders the production of more BDNF. The additional BDNF helps new neurons and their connections grow. In addition, levels of other neurotransmitters are increased after a strenuous exercise session.
"Dopamine, serotonin, norepinephrine — all of these are elevated after exercise," says Ratey. "So having a workout will help focus, calming down, and impulsivity — it's like taking a little bit of Prozac and a little bit of Ritalin."
Research showing a link between fitness and academics is growing.
The California Department of Education (CDE) looked for a correlation between fitness scores and test scores. They found that kids who were deemed fit (by a standard test of aerobic capacity, BMI, abdominal strength, trunk strength, upper body strength and overall flexibility) scored twice as well on academic tests as those that were unfit. In the second year of the study, socio-economic status was taken into account, to possibly eliminate that variable as an explanation. As expected, those in the upper-income brackets scored better overall on the academic tests, but within the lower-income set of students, the same results were observed — kids who were more fit performed better academically.
Charles Hillman, associate professor of kinesiology at the University of Illinois, was able to duplicate these findings with 259 third and fifth-grade Illinois students. His team also noticed that two of the tests, BMI and aerobic capacity, were significantly more influential to higher academic scores than the other four fitness factors. Digging deeper, he isolated two groups of 20 students, one fit and the other unfit. They were given cognitive tests of attention, working memory and processing speed while their brain's electrical activity was being measured by an electroencephalogram (EEG) test.
The fit kids' brains showed more activity in the prefrontal cortex, known for its executive function and control over other brain processes.
So, just send the kids on a fast jog and they will ace all of their tests? Not quite.
“The exercise itself doesn't make you smarter, but it puts the brain of the learners in the optimal position for them to learn,” Ratey said. “There's no way to say for sure that improves learning capacity for kids, but it certainly seems to correlate to that."
Facial expressions of emotion are hardwired into our genes, according to a study published today in the Journal of Personality and Social Psychology. The research suggests that facial expressions of emotion are innate rather than a product of cultural learning. The study is the first of its kind to demonstrate that sighted and blind individuals use the same facial expressions, producing the same facial muscle movements in response to specific emotional stimuli. The study also provides new insight into how humans manage emotional displays according to social context, suggesting that the ability to regulate emotional expressions is not learned through observation.
San Francisco State University Psychology Professor David Matsumoto compared the facial expressions of sighted and blind judo athletes at the 2004 Summer Olympics and Paralympic Games. More than 4,800 photographs were captured and analyzed, including images of athletes from 23 countries.
"The statistical correlation between the facial expressions of sighted and blind individuals was almost perfect," Matsumoto said. "This suggests something genetically resident within us is the source of facial expressions of emotion."
Matsumoto found that sighted and blind individuals manage their expressions of emotion in the same way according to social context. For example, because of the social nature of the Olympic medal ceremonies, 85 percent of silver medalists who lost their medal matches produced "social smiles" during the ceremony. Social smiles use only the mouth muscles whereas true smiles, known as Duchenne smiles, cause the eyes to twinkle and narrow and the cheeks to rise.
"Losers pushed their lower lip up as if to control the emotion on their face and many produced social smiles," Matsumoto said. "Individuals blind from birth could not have learned to control their emotions in this way through visual learning so there must be another mechanism. It could be that our emotions, and the systems to regulate them, are vestiges of our evolutionary ancestry. It's possible that in response to negative emotions, humans have developed a system that closes the mouth so that they are prevented from yelling, biting or throwing insults."
The report, a collaboration of the U.S. Environmental Protection Agency (EPA); the National Oceanic and Atmospheric Administration (NOAA); the U.S. Geological Survey (USGS); the U.S. Fish and Wildlife Service; coastal states; and the National Estuary Program, assessed America's coastal conditions using five indicators of condition: water quality, sediment quality, benthic community condition (the health of the water's bottom-dwelling invertebrate species), coastal habitat loss as indicated by changes in wetland area, and fish tissue contaminants.
The overall condition of America's coasts is rated as "fair," based on these five indicators. Comparison of the condition scores shows that overall condition in U.S. coastal waters has improved slightly since the 1990s. Coastal conditions improved in the Northeast and the West, but there were slight decreases in conditions in the Southeast and Gulf of Mexico. The conditions in the Great Lakes and Puerto Rico remained the same.
The next National Coastal Condition Report is expected to be released in 2011 and will provide an assessment of the status of U.S. coastal waters from 2003 to 2006, along with trends in condition since the 1990s.
America's coastal waters are a precious resource, providing spawning grounds, nurseries, shelter and food for a host of fish, wildlife, waterfowl, and migratory birds. They are the source of most of America's fish catch, and through fishing, boating, tourism, and other coastal industries provide millions of jobs nationwide.
The series of National Coastal Condition Reports will support more informed decisions concerning protection of coastal resources and will increase public awareness about the extent and seriousness of pollution in these waters.
To read The National Coastal Condition Report III (NCCRIII) and learn more about the indicators and criteria used in the Report, please see: http://www.epa.gov/owow/oceans/nccr/.
What do you do to pass on your genes to the next generation if you are really hard up, it’s too dark to see clearly and you are literally under enormous pressure. The short answer: play rough and weird.
Species of deep-sea squid that strut their stuff in the blackness that prevail thousands of feet beneath the ocean surface encounter few opportunities to mate and so every tryst must count.
So what's a guy (squid) to do? Males of the species Taningia danae use sharp beaks or hooks on tentacles to make cuts into their mates of more than two inches before depositing sperm packets called spermatophores, Australian biologists tell the German magazine Der Spiegel.
Males may get really agro because of an inferiority complex, the pub reports: They are generally smaller and, if they don’t play hard, fast, or clever they may get eaten by the Big Mamas. At these depths, size may matter a lot to make sure those little packets of love really stay put.
The researchers report they found spermatophores that had been “injected” into a female by a three-foot-long penis, that sometimes misses its mark. In one case of bad aim, a squid accidentally injected himself under the skin, providing perhaps the most literal example in the animal world of shooting oneself in the foot. (Another species of squid just injects the sperm into water near their female and a chemical in the sperm packet dissolves female tissue, allowing the sperm to enter.)
Some of these wimpy squid males apparently try brains instead of brawn. The men of Ancistrocheirus lesueurii are cross dressers, taking on the appearance of females, possibly as a ploy to get closer to the real thing before pouncing. Females who hail from the clan Heteroteuthis dispar are models of thrift. They store sperm in their body that accounts for up to 3 percent of their body weight.
For female squids, sex is truly a once-in-a-lifetime experience—and an apparently horrible one at that. The female releases millions of tiny eggs into the water along with the sperm contributed by the one male who got his hooks into her, and usually never goes back for seconds, the researchers found. Afterward, they never let a male get close—a behavior that even has led to the technical term “traumatic fertilization.”
Questions arise over whether Jonathan the tortoise is really that old
A giant tortoise that has been dubbed the world's oldest living creature may actually be an imposter, living under an assumed identity, it has emerged.
It had been reported that Jonathan, a present-day resident of St Helena, was living on the remote British island when Napoleon was exiled there back in 1815.
His claim to record longevity was based on a Boer War photograph of a Seychelles tortoise said to have been in the Atlantic island territory since Napoleon's time.
Both are called Jonathan and it was assumed that the tortoise now living on the governor's lawn was the one in the photograph.
But a St Helenian businessman and amateur historian, Nick Thorpe, has said he strongly suspects the creature in the picture actually died 90 years ago.
The possible confusion may have arisen because of a curious tradition among islanders of passing on nicknames from father to son.
The nickname "Dutchman", for instance, still survives among St Helenians, dating back to the days when Boer prisoners of war were kept on the island.
Mr Thorpe said: "I have a feeling that the Jonathan in the Boer War photograph died about ten years later.
"Since they have several giant tortoises on St Helena, they simply named the next largest one Jonathan.
"The date of 175 years old is being assumed because the Jonathan in the photograph of 1901 looks like the Jonathan of today.
"As they are very difficult to date, no one can say with any certainty that this current, reigning Jonathan is 176 or 150 or even 200."
It is not the first time the present Jonathan's age has been disputed.
In 1972, readers of The Times debated the issue after the former Governor of Saint Helena, Sir James Harford, revealed he owned some pictures which could shed some light on the issue.
Nick Thorpe and Lolly Young talk to school reporter Sarah about the story
In a letter dated 28 January, he said he had an aquatint picture showing two giant Seychelles tortoises on the lawn of Plantation House, the governor's residence, during Napoleon's time there.
He said a third tortoise arrived in 1882.
He also said that by 1918, two of the three had died and it was not known which one survived.
The possible identity-swap was discovered by Year 9 pupils at Banbury School in Oxfordshire.
They picked up on the story while taking part in BBC News School Report, a project that involves teaching pupils journalistic skills.Mr Thorpe happened to have been on a visit to their school with Lolly Young, a school teacher in St Helena.
It may look like the ultimate boy's toy but this scale model - pictured here for the first time - represents the future of the Royal Navy. As work begins on two 65,000-ton aircraft carriers, Live gains exclusive access to the top secret plans for Britain's biggest and most ambitious warships
A starboard view of a 1:200 scale model of what will be the two biggest warships Britain has ever launched - the 65,000-ton HMS Queen Elizabeth and HMS Prince Of Wales
At first sight it looks like a giant Airfix model, with every detail carefully replicated, from the tiny fighter jets and helicopters to the unique twin ‘island’ control towers complete with a captain and commander to survey the deck. Even the 30mm anti-aircraft guns and the long-range radar have been painstakingly reproduced. At more than five feet long, the model is a carefully crafted reminder of our glorious naval past carved out of grey plastic.
Such vast aircraft carriers may once have been a badge of pride, but now you can’t help but feel they are merely lumbering relics of the Cold War or even the Empire, which have surely had their day. After all, the UK abandoned the idea of aircraft carriers in the late Seventies when our last big carrier, the HMS Ark Royal, was scrapped.
But this long hunk of plastic represents a work in progress. It sits proudly in the lobby of the design headquarters for the Royal Navy’s latest grand project. It’s a 1:200 scale model of what will be the two biggest warships Britain has ever launched – the 65,000-ton HMS Queen Elizabeth and HMS Prince Of Wales.
Each ship will have nine decks topped by a vast flight deck and will tower six metres taller than Nelson’s Column from keel to masthead.
‘Cover the flight deck with grass and it would be a par four,’ says one of the design team.
They will carry 36 state-of-the-art Joint Strike Fighter stealth jump-jets and four helicopters each, and be able to get 24 planes airborne within just 15 minutes.
‘All the major navies in the world are now building them,’ says Dr Lee Willett, head of the Maritime Studies Programme at the Royal United Services Institute.
‘The Russians have one of their big carriers, the Admiral Kuznetsov, back at sea and have stated that they plan to build 12 carrier battle groups. The Chinese and the Indians are also under way with plans, the Japanese are building a destroyer that will act as a helicopter carrier and the US are working on new-generation carriers.
‘We’re an island nation and we have global interests so we need these four acres of moveable sovereign airfield that we can deploy wherever we want, whenever we need them.’
Aerial view, showing the take-off ramp (A), the giant lifts (B), the runway (C), and the helicopter (D)
What the building of the carriers also shows is that Britain is running out of friends.
Willett says, ‘The world is an unstable place and, post-Iraq and the global war on terror, access to other nation’s territory or airspace is more difficult.’
Former naval officer and now author Lewis Page agrees.
‘Friendly nations are hard to find and it becomes even harder once you have taken over local air bases, which are then vulnerable to attack.
'But there is a way to avoid giving yourself a logistical nightmare and becoming a target. Without having to ask anyone you can put an aircraft carrier 15 miles offshore in international waters and carry out operations from there without a single person needing to set foot on land or a single supply convoy coming under fire.
'And you won’t need to go through any diplomatic hoops.’
Despite the persuasive arguments, our two supercarriers have had a long and painful birth. The decision to build them was announced in the 1998 Strategic Defence Review, but the official signing ceremony only came a decade later, in July this year.
Now the Defence Secretary has announced the carriers will be further delayed – they are not expected to be ready for final delivery until 2016 and 2018.
Meanwhile, work continues at Rosyth dockyard on the Firth Of Forth to expand the granite sides of the massive Number One dock. It is here that the final assembly of the carriers will take place – or at least, that’s the plan.
But there are troubled waters ahead for this huge project, which still has the potential to go spectacularly wrong. Britain has never put together a ship in this way, on this scale, and there are fears over whether we have the commitment or the skilled workers to build the vessels to order and on time.
A computer-generated image of the new carrier
There have been criticisms of cost-cutting measures, concerns linger over whether the engines will work and, just to add to the uncertainty, the planes it is hoped will fly off the carriers have yet to be built.
From the outside it looks like any other nondescript provincial HQ, with a few well-manicured bushes and rows of family saloon cars parked neatly in front. But it’s on this unassuming industrial estate in suburban Bristol that the Royal Navy’s latest strike force is being designed.
Live has been given exclusive access to the design team, to watch them at work on blueprints and on computer designs for the new carriers, the UK’s most impressive piece of military kit for decades.
Within the open-plan office there are 180 people, among them 150 designers. I’m introduced to the design team in a meeting room, on one wall of which are pinned rows of detailed diagrams of the nine decks of the CVF (CV is the hull classification for a Carrier Vessel, while F stands for Future). We are prohibited from taking pictures as the diagrams are protected by the Official Secrets Act.
‘The project has been going for ten years and this is the third ship we’ve worked on,’ says naval architect Simon Knight, the project’s Platform Design Director.
‘We spent two years working on a bigger ship but found she was much too expensive, then a year on a smaller ship, but we couldn’t fit in everything we needed. We’ve been working on the CVFs now for the past three-and-a-half years.’
In the past, the team would have had to build life-size sections in plywood, but today most of the design and simulation is done on computers. Eddie Chambers, from Tyneside, is responsible for the intricate CAD (computer-aided design) 3D models of the ship. Built up in meticulous detail, these even show individual pipes and electrical cables.
He offers me a virtual tour of the engine room, then calls up one of the mess halls, complete with tables and chairs.
‘This allows you to walk around the ship,’ he says, ‘and means we can make sure that when we tell the build people to start they’ll know exactly where everything has to go. These ships are going to be huge, the second biggest in the world. Only the Yanks have got one bigger – and it’s good to know that at least we’ll have a bigger one than the French.’
Putting the ship together should be like assembling a Lego model. But with blocks of up to 10,000 tons
No single shipyard in this country has the infrastructure or personnel to construct the entire ship, so the plan is to build them in sections in different shipyards. Work on the lower bow section has already begun in Devon. The other shipyards are set to begin cutting steel in March 2009.
The aft block will be built in Glasgow, the central block in Barrow-In-Furness and the forward section in Portsmouth. The remaining upper sections will be constructed in smaller docks; bids from shipyards are still being considered.
The blocks will then be transported independently to Rosyth to be put together. The integration process is scheduled to take around two years and the plan is that as soon as the first ship floats it will leave and then work will begin on the second.
Putting aside questions over whether the money or political will could dry up before these carriers are completed, simply the practicality of gathering the parts together is a logistical nightmare.
‘Transportation is one of our biggest problems,’ says Knight. ‘Ideally you would build part of the ship in a dock, flood the dock, float the section of ship out and tow it to Rosyth, where you float it into another dock and let the water out so it’s left resting on blocks. You then connect it to the next section.
‘But unfortunately the aft section doesn’t float. We’ve looked at barges to transport it, but there’s only one big enough to take that weight and who knows if that barge will be around when we need her.
‘Alternatively we could put tanks on her to give extra buoyancy – basically enormous floats. But this is risky because we’ll have to tow it from the west coast of Scotland to the east coast.’
A close-up of the forward tower on the 1:200 scale model
If and when all the pieces do finally meet, then putting the thing together should be like assembling a Lego model. But this is a massive undertaking – each of these gigantic blocks will weigh up to 10,000 tons.
‘Joining these enormous sections together, physically hammering them along a block and then making sure they’re exactly aligned will be a pretty hairy operation,’ says Knight.
The procedure has been carried out before to build offshore rigs, and the Navy is using it for its Type 45 destroyers, but those are small projects compared to these monsters. Each of these blocks will be bigger than a Type 45.
Even if things run smoothly this far, there are no guarantees that the ship will actually move. Simon Knight admits that nervousness will continue until the moment that HMS Queen Elizabeth finally goes into the water.
‘The speed trials, scheduled to take place off Rosyth, will certainly be nerve-racking. You can estimate how well the propellers will drive the ship forward, but until you’re full-scale in the water it’s very hard to know for certain. So when they first launch the ship, I’ll be terrified.’
The £3.9 billion cost for two carriers may seem huge, but they are built to serve for 50 years, and the budget is significantly less than for American carriers – each new ship costs $14 billion (£9 billion).
The project team admits that designing a ship with the desired features to a tight budget has been challenging. The result, they say, is notable more for simplicity and efficiency rather than hi-tech innovation. The most revolutionary element of the CVF design is its highly mechanised weapons handling system, which means a cut in the crew numbers required – from 4,500 on a US carrier (including a team of 150 just to move the weapons around) to 1,450.
One of the first things to go was nuclear power. Most modern aircraft carriers, including the American ships, are powered by an on-board nuclear reactor.
‘This is a brand-new ship, so getting through all the safety aspects of nuclear power would have been hideously expensive,’ says Knight.
Instead, like modern cruise liners, the HMS Queen Elizabeth and HMS Prince Of Wales will be propelled by electrical motors, powered by two Rolls-Royce gas turbines and four diesel generators. The diesel generators are more economical and used for general cruising, but when you need to get somewhere fast or need more headwind to help the planes to take off then you switch to the gas turbines.
Money has also been saved in side armour protection, though Knight insists this was a strategic rather than a budgetary issue.
‘The CVF’s first line of defence is the frigates and the new Type 45 destroyers around us,’ he adds. ‘Our only self-defence is close-in weapons systems and small guns. Instead, what you have on the ship is 36 of the most lethal aircraft ever made.’
That would be fine except that the Joint Strike Fighter (JSF) jump-jets requested are still in early flight tests and engine problems mean they will not even attempt vertical take-off until next year.
‘It’s much easier with an existing aeroplane,’ says Aviation Design Manager Gary Davey. ‘Our ramp design has already been completed but the JSF’s undercarriage is still evolving.’
Areminder of the worth of aircraft carriers as mobile airfields was provided by the Falklands War in 1982. HMS Invincible and HMS Hermes had been built as ‘through-deck cruisers’, to carry hunter-killer groups of Sea King anti-submarine helicopters, which were capable of tracking down and destroying Soviet subs in the north Atlantic should the Cold War ever spill over into open conflict.
The four or five Sea Harrier planes also aboard were simply there to protect the ship from attacks by other aircraft. But then the ships were hastily reconfigured to carry eight Harrier jets in the Falklands crisis, and they proved invaluable in getting air power over their targets.
In these turbulent times, ‘power projection’ is once again considered a necessity. As complications over finding host nations and even getting agreement on using air space grow, so does the value of the carrier, which has been vital in the ongoing war in landlocked Afghanistan.
‘That started out as a carrier-based operation,’ says Dr Willett. ‘Finding shore bases can be politically difficult, and there’s also the question of whether they are of a sufficient standard. Upgrading them can be politically difficult and expensive. Carriers have proved their value in humanitarian and relief operations as well as in combat roles, and they remain a very flexible political and military asset.
Even if it’s not politically desirable to put troops ashore somewhere, you can fly aircraft overhead, use some ordnance against a specified target, or just deliver a warning simply by having a carrier parked offshore.
‘And you can do all this from your own sovereign territory in international waters and no one can tell you that you can’t.’
THE FLOATING AIRBASE
• The surface of the16,000sqm flight deck is covered in a grainy,heat-resistant paint,similar to very coarse sandpaper. The entire painted surface amounts to 370 acres - slightly bigger than Hyde Park.
• Two huge lifts, each with a 70-ton capacity, are capable of transporting two aircraft from the hangar to the flight deck in 60 seconds. The ship will be home to 36 Lockheed Martin F-35B Joint Strike Fighters and four EH-101 Merlin helicopters.
• The ground-breaking twin-island layout allows more deck space for aircraft and better visibility of the flight deck. The forward island is for navigating the ship; flight control is based in the aft island.
• The ship's 29,000 sq m hangar is 150 metres in length and has 20 slots for aircraft maintenance.
• There are 11 full-time medical staff on board managing an eight-bed medical suite, operating theatre and dental surgery.
• An onboard water treatment plant produces over 500 tons of fresh water daily.
• Two Rolls-Royce MT30 gas turbines and four diesel generator sets produce 109MW - enough to power a town the size of Swindon.
• Cabins are spacious and cruise-liner style, with en-suite toilets and shower facilities. Officers and senior ratings have single or two-berth cabins. The maximum number of crew in a cabin is six.
• The carrier will carry more than 8,600 tons of fuel, enough for the average family car to travel to the Moon and back 12 times. This gives a range of up to 10,000 nautical miles.
• Top speed will be in excess of 25 knots, sufficient to cross from Dover to Calais in an hour.
As always, as the year comes to a close, there is an inevitable rush to produce top 10 lists. Top 10 movies, top 10 books, top 10 music albums. Not content to let Hollywood and the entertainment industry have all the fun, the news staff at Science magazine have compiled their year-end top 10 list of the scientific breakthroughs that broke through with the potential for lasting impact. These range in scale from protons to planets and include nearly everything in between.
Science's Breakthrough of the Year: Reprogramming Cells
As the writers at Science spin the opening sentence, the breakthrough of the year is "a long-sought feat of cellular alchemy." Whereas the ancient alchemists sought to transmute mundane metals into gold or silver, modern scientific wizards have found ways to convert human skin cells—the base metal—into induced pluripotent stem cell (iPS)—the modern biological equivalent of gold. These iPS cells are capable of growing into a variety of tissues, which could ultimately lead to the capacity to cure certain diseases with a patient's own cells.
In a second cellular programming trick, scientists transformed mature cells in live mice from one specialized type to another. This bit of biological witchcraft flew in the face of years of results that suggested that cell development was a one-way street. It has provided much greater understanding into the nature of biological and chemical processes that enable cells to stably adopt a specialized role, and has opened the doors to the field that's now being called cellular programming. Both of these techniques potentially side stepp the political mine-field that surrounds human embryonic stem cells.
Ten years ago, a team from the University of Wisconsin-Madison developed a technique to get human embryonic stems cells (hES) from human blastocysts. This, not terribly surprisingly, ignited a large debate over bioethics since the procedure often destroys the blastocyst. The potential for a new source of embryonic-like stem cells came via breakthrough paper from a team of Japanese researchers. Named the number two breakthrough of the year by Science magazine, the Japanese team created iPS cells from mouse tail cells through the simple insertion of four genes. When the next logical step was taken—using the technique with human cells—researchers were off to the races.
Two groups announced stunning breakthroughs within weeks of each other this year. The first group derived iPS cells from the skin of an elderly woman suffering from amyotrophic lateral sclerosis (ALS, or Lou Gehrig's disease). They then directed the cells to develop into neurons and glia, two of the cell types most affected by ALS. Shortly after this announcement, a second group reported the creation of patient-specific iPS cell lines for 10 additional diseases. Many of these 10 disease are not well suited, or even possible, to study via animal models.
Ignoring the lure of stem cells, another group of researchers demonstrated that one does not need them to produce various mature cell types; instead, they forced mature cells to change their form and function. Working with live mice, an American research team demonstrated that pancreatic exocrine cells can be forced to function as beta cells. Using a trio of viruses as their gene delivery vectors, the team inserted a set of genes believed to be responsible for beta cell growth into the exocrine cells. Within days, they observed that the "treated mice formed insulin producing cells that acted like bona fide beta cells." Since beta cells are responsible for producing insulin and are destroyed in people suffering from type-I diabetes, this technique could have major ramifications if it can be modified for human use.
While these breakthroughs are major, much more work is needed before we start to see custom-made, individually constructed cures for diseases. We currently lack a reliable method of triggering developmental changes and need a more detailed understanding of how the conversion process works and a much more detailed understanding of the nature of the newly formed cells. Even though this field is not ready for human consumption, the potential it presents warranted it being named the biggest scientific breakthrough of the year, according to Science.
- Direct Views of Exoplanets: Astronomers first found a planet orbiting another star in 1995, after hundreds of years of speculation that the probability of other planets must be infinitesimally close to unity. In the intervening 13 years, 332 more planets have been found orbiting other stars. Until earlier this year, however, all were found using indirect techniques. The vast majority of these exoplanets—307 to be exact—were found not because we saw the planet, but because we were able to observe the star it orbits wobbling due to the planet's mass. Starting in the latter part of this year, astronomers have been reporting on the direct observation of exoplanets. Using adaptive optics and "virtual coronograph" software, teams have found 11 planets by directly looking at them, rather than relying on secondary effects.
- The DNA of Cancer: It is known that DNA mistakes can lead to cell growth that is unregulated, which can produce a cancerous tumor. Thanks to the completion of the human genome and affordable sequencing equipment, several groups have looked deeper into the genetic mistakes that can cause cancer. Through the study of various cancer genomes, scientists have concluded that treatments that block common cellular pathways could be more effective then a 'magic bullet' treatments directed at individual cancer genes.
- New Class of High-T Superconductors: since the discovery of high-temperature superconductors in 1986, all had been a ceramic made up of lanthanum-barium-copper oxides. Earlier this year, there was a flurry of papers from a number of research groups that announced they had found a new class of high-temperature superconductors, ceramics made of lanthanum, iron, arsenic, oxygen, and fluorine. While their critical temperature is, by high-temperature superconducting standards, a not-so-hot 55 K, they have opened a new pathway into the mystery of superconductor research. Follow up work hasn't been able to determine whether these materials behave the same as their more familiar cuprate cousins.
- Protein flopping and folding: How proteins dock with target molecules has long been a subject of debate among biologists, biochemists, and biophysicists. The leading theory is that, when a protein molecule comes upon a target, it will change its shape so that it will fit in a lock-and-key manner. However, some postulated that proteins in solution randomly oscillate between a number of related but slightly different conformations. New computational biology work performed by teams in the US and Germany has given support to the latter model. The researchers discovered that a oft-studied protein will "dance" between many different configurations before finding the one that enables it to interact with its target molecule.
- Splitting Water: With the summer's historic rise in oil prices, interest in renewable energy sources was front and center view in the mind of many people. Even as technology for solar and wind power advances and prices for the power they generate falls, storing that energy remains a challenge. One suggestion is to hydrolyze water into hydrogen and oxygen, which can later be burned or used in a fuel cell setup. The problem is efficiently spitting water; platinum is a good catalyst for this reaction, but its scarcity and price are turn offs for large scale work. This year saw the development of a new catalyst, comprised of phosphorous and cobalt, that can efficiently hydrolyze water on industrial scales.
- Beginning of Life, the Movie: Most of us have have probably seen a video of the first cells of an embryo dividing, starting from a sperm+egg, then dividing to form the first few dozen individual cells. When it comes to vertebrates, though, scientists only had, at best, a partial view of what comes next. This year, researchers from Germany created a specialized microscope and observed the formation and growth of a zebrafish embryo. They watched it from a single cell until it reached a cluster of almost 16,000 individual cells. The movies are freely available on the Internet, and well worth watching.
- Color Coded Fat: It has been known for over 400 years that there are two types of fat: white and brown. Brown fat cells have a much higher concentration of mitochondria and burn energy for heat; white fat cells are what many of us readily see in our midsection. Both types of fat cells were assumed to be related and come from the same progenitor cell type. Using the observation that the gene PRDM16 spurs specialization of brown fat, US researchers expected that if they blocked PRDM16 activity, the brown fat precursor cells would become white fat cells. They did not get what they expected as, in the absence of PRDM16, the brown fat cells of mice turned into muscle cells. The team was also able to reverse the process, turning cells differentiating into muscle cells into brown fat. Using a technique to trace cell linages, the team found that muscle and brown fat cells in mice were related, but neither was related to white fat cells.
- Computing the Basics: While protons, neutrons, and other light hadrons are considered basic particles, the mathematics describing their innards is incredibly complex. The simple picture of the inside of any hadron is three quarks that exchange gluons, the messenger particle of the strong nuclear force, among themselves. Reality is much more complicated, and our best description of the strong force—quantum chromodynamics (QCD)—requires incredibly powerful computers to have any hope of accurately modeling even a "simple" hadron. Using massively parallel computers and a technique known as lattice quantum chromodynamics, researchers in Europe have predicted the mass of a proton using only the theory behind the strong force. The fact that their computed mass is within a few percent of the experimental answer suggests that QCD properly describes the strong nuclear force.
- DNA on the Cheap: When the human genome was decoded a few years ago, it used techniques that are now considered somewhat antiquated. Hardware from a number of companies has become available over the past few years has blown the doors off genome sequencing. The "sequencing by synthesis" technology from 454 Sequencing (now owned by Roche) has allowed researchers to to sequence partial genomes of extinct cave bears and Neanderthals, along with 80 percent of a woolly mammoth's. As sequencing technology advances, more and more genetic codes will be cracked and, like in consumer technology and electronics, the price will continue to fall.
If you’re a woman, you’re more likely to give and to give equal amounts to both groups.
Winterich, who teaches marketing at Texas A&M’s Mays Business School, says she can predict charitable behavior to different groups by an individual based on just two factors: gender and moral identity. (Moral identity does not measure how moral a person actually is, but rather how important it is to that person to be caring, kind, fair, honest, etc.)
The research is forthcoming in the Journal of Consumer Research . Co-authors on the paper are Vikas Mittal at Rice University and William T. Ross at Penn State University.
The results of Winterich’s studies involving American participants have implications for those in the fund-raising arena.
The study examined how people responded to a need within an “ingroup” and an “outgroup.” An ingroup has an obvious connection to the potential donor, such as physical proximity or ethnicity, while the outgroup might have nothing more than humanity to relate it to the donor.
In the study, participants completed a survey to gauge their moral identity. Later, each was given five $1 bills and three options: keep the cash, give it to a Hurricane Katrina relief fund, or give it to a relief fund for victims of the Indian Ocean tsunami.
The results were very consistent. Women with higher moral identity were more likely to split their dollars evenly between the two charities. Women with lower moral identities gave more to the ingroup (Katrina victims).
Men with high moral identities gave to the ingroup, but seldom to the outgroup (tsunami victims). Men with low moral identities pocketed the cash.
Winterich’s work reinforces other studies of moral identity that show its correlation to how an individual expands his or her bubble of concern to include others. Low moral identity indicates a person will be more focused on self; high moral identity means a person will be more focused on others.
The bottom line for fundraisers, says Winterich, is that they need to examine how they position themselves relative to their potential donor. Charities must focus on the relationship between the donor and the cause to ensure that the charity is viewed as an ingroup, particularly if men are the target. Also, since women tend to be more generous, charities should target them specifically whenever possible.
Additionally, priming a potential donor to think about their moral identity can make them more charitable than they might otherwise be.
There was one other surprise from this study. “It was shocking to me how much they gave,” Winterich says. “I think it says good things for society.”
A Canadian college student majoring in chemistry built himself a home lab - and discovered that trying to do science in your own home quickly leads to accusations of drug-making and terrorism.
Lewis Casey, an 18-year-old in Saskatchewan, had built a small chemistry lab in his family's garage near the university where he studies. Then two weeks ago, police arrived at his home with a search warrant and based on a quick survey of his lab determined that it was a meth lab. They pulled Casey out of the shower to interrogate him, and then arrested him.
A few days later, police admitted that Casey's chemistry lab wasn't a meth lab - but they kept him in jail, claiming that he had some of the materials necessary to produce explosives. Friends and neighbors wrote dozens of letters to the court, testifying that Casey was innocent and merely a student who is really enthusiastic about chemistry.
On December 24, Casey was finally released into his parents' custody, pending a trial to determine whether he was building what police called "improvised explosive devices." Yesterday Casey's lawyer told local journalists:
My client is a very intelligent young man . . . he's very keen in chemistry, a very curious young person and very capable, very knowledgeable in the area and he was always curious with regard to chemistry, chemical compounds, chemical reactions, that kind of thing. So from my client's point of view, it's completely innocent insofar as he had no intention of creating any explosives or explosive devices. As people probably know, anything in your house can constitute or be used in chemical or explosive devices, including sugar and cleaning compounds, Mr. Clean, bleach, detergents, all those sorts of things.
It's unclear what made police raid Casey's house. They claim that they got a tip from a woman who sold Casey fertilizer and was concerned about it. Certain kinds of fertilizer are used in the production of crystal meth.
The case is reminiscent of the Steve Kurtz case in 2004. Kurtz is a New York artist who uses biotech equipment in his work, and police arrested him on suspicion of terrorism after discovering his home chemistry lab.
Casey is now living at home, but he is no longer allowed to engage in chemistry experiments except under supervision in school labs. He is also required to inform the chemistry department of the charges against him. His trial continues on January 26.
This is a stark example of how scientific curiosity is still regarded with suspicion - even in an era where home labs are becoming more and more common. Good luck to Casey - let's hope his next home lab is even bigger and cooler than the one he recently lost.
CHEYENNE, Wyo. (AP) — Yellowstone National Park was jostled by a host of small earthquakes for a third straight day Monday, and scientists watched closely to see whether the more than 250 tremors were a sign of something bigger to come. Swarms of small earthquakes happen frequently in Yellowstone, but it's very unusual for so many earthquakes to happen over several days, said Robert Smith, a professor of geophysics at the University of Utah.
"They're certainly not normal," Smith said. "We haven't had earthquakes in this energy or extent in many years."
Smith directs the Yellowstone Seismic Network, which operates seismic stations around the park. He said the quakes have ranged in strength from barely detectable to one of magnitude 3.8 that happened Saturday. A magnitude 4 quake is capable of producing moderate damage.
"This is an active volcanic and tectonic area, and these are the kinds of things we have to pay attention to," Smith said. "We might be seeing something precursory.
"Could it develop into a bigger fault or something related to hydrothermal activity? We don't know. That's what we're there to do, to monitor it for public safety."
The strongest of dozens of tremors Monday was a magnitude 3.3 quake shortly after noon. All the quakes were centered beneath the northwest end of Yellowstone Lake.
A park ranger based at the north end of the lake reported feeling nine quakes over a 24-hour period over the weekend, according to park spokeswoman Stacy Vallie. No damage was reported.
"There doesn't seem to be anything to be alarmed about," Vallie said.
Smith said it's difficult to say what might be causing the tremors. He pointed out that Yellowstone is the caldera of a volcano that last erupted 70,000 years ago.
He said Yellowstone remains very geologically active — and its famous geysers and hot springs are a reminder that a pool of magma still exists five to 10 miles underground.
"That's just the surface manifestation of the enormous amount of heat that's being released through the system," he said.
Yellowstone has had significant earthquakes as well as minor ones in recent decades. In 1959, a magnitude 7.5 quake near Hebgen Lake just west of the park triggered a landslide that killed 28 people.
Amazing footage of the moment a group of kayakers and fishermen found themselves being circled by a great white shark has been released.
By Jon Swaine
One of the group was even knocked into the water by the shark, and was forced to tread water while the man-eating creature circled him for a minute.
The incident took place in Sydney, Australia, on the same day that Brian Guest, of Perth, was killed by a shark on the other side of the country.
Steve Kulcsar, the 29-year-old kayaker who was knocked overboard, told the Australian Daily Telegraph: "A fisherman yelled out, 'There's a 5m shark coming your way.' We all thought he was just trying to stir us up for a laugh, but a few moments later, a big fin appeared."
Mr Kulcsar recalled the moment the shark bumped him into the water. "I wasn't really worried about the shark, actually," he told the newspaper. "I knew it was there, but my first thought was to just get back in the kayak as quick as possible."
He said that making a quick change in direction could have been what prompted the shark to go for his boat.
"When it cruised past me, I thought I was safe, so I went as quickly as I could in the opposite direction," he said. "I think that was my mistake, because then it turned around and chased me. If I had stayed still, I think I would have been OK."
After a minute in the water, Mr Kulcsar was able to climb back into his kayak. The fishermen then hauled him into their boat. After ten nervy minutes, the shark lost interest in the group and swam away.
Mr Kulcsar added: "I'm not really shaken up at all. At the time I was, but now I'm just having a few beers."
A Rainbow forms over the Ulu Baram rainforest in eastern Malaysia. The country is zooming in on forests with a satellite in order to fight illegal logging which its government says is harming the major timber exporting country.
Malaysia is zooming in on forests with a satellite in order to fight illegal logging which its government says is harming the major timber exporting country, a report said Sunday.
Darus Ahmad, deputy director-general with the Malaysian Remote Sensing Agency, said the "eye in the sky" programme was put in place in October.
"There is always criticisms that our forests are diminishing," he was quoted as saying by the New Sunday Times newspaper.
Darus said that using satellite images the authorities can establish a national forest inventory of the country's total area of forest cover.
They can then check whether logging in a particular area is legal or not, he said, adding that the facility was currently available in the western peninsular part of Malaysia only.
Darus also said the system can be used to prevent air pollution by detecting forest fires and illegal land clearing.
In the 1990s alone, Malaysia lost more than 13 percent of its forests, with much of the deforestation on the island of Borneo, which it shares with Indonesia and Brunei.
The World Wildlife Fund at the time estimated that illegally logged trees made up about one third of Malaysia's timber exports.
Prime Minister Abdullah Ahmad Badawi last year pledged not to indiscriminately approve logging licences, amid mounting concern that clearances are threatening endangered species and tribal communities.
Deputy Prime Minister Najib Razak, who also heads the National Forestry Council, later warned that illegal logging could undermine Malaysia.
"It can jeopardise our efforts to preserve biodiversity, flora and fauna and have an impact on global warming. At the international level, illegal logging portrays a negative image of our country," he said.
"It can harm our national economy as the timber industry produces 23 billion ringgit (6.8 billion dollars) worth of wood-based products a year," he added.
The European Union market accounts for about 30 percent of Malaysia's annual timber exports.
There are few things more enjoyable on a freezing day than a vigorous game of tag followed by a hearty meal.
Unless you're supposed to be the main course, that is.
These pictures show how close one man came to being a polar bear's dinner.
Mmmm, looks like dinner time: The bear stands on its haunches and peers over the car roof at his prey, a surveyor returning to his vehicle in the Alaskan town of Barrow
The chase is on: The man has his glove off, but not enough time to unlock his car door
The target, a surveyor, was returning to his car in the remote town of Barrow, Alaska, when he saw the great white beast.
With no time to unlock the door of his vehicle and climb inside, he tried to duck out of sight.
He's coming to get you: The hungry bear makes his move
Yikes: The bear lumbers around the car as the man sprints for his life
But the hungry bear was not giving up, and a terrifying chase began.
First, the beast stood up on its furry haunches and eyed its prey. Then it loped around the car, and even climbed over the bonnet to try to reach him.
Last resort: The man, desperate for shelter, makes a break for a neighbouring truck
Phew: He slips inside the unlocked truck, nursing more than 100 scratches
After a few laps of the car the bear almost caught up, managing to land a few heavy swipes on his prey.
The man eventually managed to take refuge in a neighbouring truck which was unlocked.
His back and head were covered in more than 100 deep scratches where the massive claws had managed to rip through his thick winter clothes and padded coat.
Barrow is the northernmost town of the United States, 340 miles north of the Arctic Circle.
Polar bears are frequently spotted around the area.
They are the world's largest land predator, and are the only animals that actively hunt humans.
Adult bears grow up to 10ft tall and can weigh 95 stone.
They are predominantly carnivores, eating seals, fish, reindeer, seabirds and even whales and baby walruses.
Environmentalists have warned that there could be as few as 22,000 left in the wild, and that they face extinction because the ice they live on is melting.
The wildlife group Polar Bears International says only one person has been killed by a polar bear in the U.S. in the past 30 years.
In Canada eight have been killed and in Russia, 19.
A spokesman said: 'In all instances in which a human was killed by a polar bear, the animal in question was undernourished or had been provoked.'
Wildlife groups have warned that increasing numbers of the giant bears have been spotted near towns and villages because they are trying to scavenge food.