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LOS ANGELES, July 18 (Xinhua) -- The spacecraft Dawn of the National Aeronautics and Space Administration (NASA) has returned the first close-up image of the giant asteroid Vesta after entering its orbit for the first time last week, the Jet Propulsion Laboratory (JPL) announced on Monday.The image taken for navigation purposes shows Vesta in greater detail than ever before, said JPL in Pasadena, California.On July 15, Dawn became the first probe to enter orbit around an object in the main asteroid belt between Mars and Jupiter.When Vesta captured Dawn into its orbit, there were approximately 9,900 miles (about 16,000 kilometers) between the spacecraft and the asteroid.Vesta is 330 miles (about 530 kilometers) in diameter and the second most massive object in the asteroid belt.NASA's Dawn spacecraft obtained this image with its framing camera on July 17, 2011. It was taken from a distance of about 9,500 miles (15,000 kilometers) away from the protoplanet Vesta. Each pixel in the image corresponds to roughly 0.88 miles (1.4 kilometers). Ground- and space-based telescopes have obtained images of Vesta for about two centuries, but they have not been able to see much detail on its surface."We are beginning the study of arguably the oldest extant primordial surface in the solar system," said Dawn principal investigator Christopher Russell from the University of California, Los Angeles, which is responsible for Dawn's mission science. " This region of space has been ignored for far too long. So far, the images received to date reveal a complex surface that seems to have preserved some of the earliest events in Vesta's history, as well as logging the onslaught that Vesta has suffered in the intervening eons."Vesta is thought to be the source of a large number of meteorites that fall to Earth. Vesta and its new NASA neighbor, Dawn, are currently approximately 117 million miles (about 188 million kilometers) away from Earth. The Dawn team will begin gathering science data in August.Observations will provide unprecedented data to help scientists understand the earliest chapter of the solar system and pave the way for future human space missions, according to JPL."Dawn slipped gently into orbit with the same grace it has displayed during its years of ion thrusting through interplanetary space," said Marc Rayman, Dawn chief engineer and mission manager at NASA's JPL. "It is fantastically exciting that we will begin providing humankind its first detailed views of one of the last unexplored worlds in the inner solar system."Although orbit capture is complete, the approach phase will continue for about three weeks. During approach, the Dawn team will continue a search for possible moons around the asteroid; obtain more images for navigation; observe Vesta's physical properties; and obtain calibration data.In addition, navigators will measure the strength of Vesta's gravitational tug on the spacecraft to compute the asteroid's mass with much greater accuracy than has been previously available, according to JPL.Dawn will spend one year orbiting Vesta, then travel to a second destination, the dwarf planet Ceres, arriving in February 2015. The mission to Vesta and Ceres is managed by JPL for the agency's Science Mission Directorate in Washington.Dawn is a project of the directorate's Discovery Program, which is managed by NASA's Marshall Space Flight Center in Huntsville, Alaska.

SAN FRANCISCO, July 20 (Xinhua) -- Google announced on Wednesday that it has reached a deal with author J.K. Rowling to launch the series of Harry Potter ebooks on Google's platform.When the series of Harry Potter ebooks launch on Pottermore.com in early October, the bestsellers will be available in the United States via Google eBooks platform, said Google in a blog post.When customers buy a Harry Potter ebook from Pottermore.com, they will be able to choose to keep it in their Google's online library in the cloud, as well as other e-reading platforms.Google said Google eBooks can be read on most devices with a modern browser, through Google apps for iOS and Android smartphones and tablets, and on more than 80 e-readers.Meanwhile, Rowling will continue to issue announcements via YouTube, as she announced Pottermore.com in June.The two sides also agreed to make Google Checkout the preferred third-party payment platform for all purchases made on Rowling's Pottermore.com.Pottermore.com, which will be launched on July 31, will sell ebook and audiobook versions of the seven Harry Potter novels, as well as additional content including background details and settings.According to The Times, the Harry Potter brand value is estimated to be more than 15 billion U.S. dollars. The deal could make Google move some e-reader customers from competitors like Amazon, whose e-reader Kindle does not support Google eBooks.

WASHINGTON, July 15 (Xinhua) -- Researchers at Mount Sinai School of Medicine have found that grape seed polyphenols -- a natural antioxidant -- may help prevent the development or delay the progression of Alzheimer's disease.The research, led by Giulio Pasinetti, was published online Friday in the Journal of Alzheimer's Disease, which causes brain changes that gradually get worse.This is the first study to evaluate the ability of grape- derived polyphenols to prevent the generation of a specific form of amyloid (A) peptide, a substance in the brain long known to cause the neurotoxicity associated with Alzheimer's disease.In partnership with a team at the University of Minnesota, Pasinetti and collaborators administered grape seed polyphenolic extracts to mice genetically determined to develop memory deficits and A neurotoxins similar to those found in Alzheimer's disease. They found that the brain content of the A*56, a specific form of A previously implicated in the promotion of Alzheimer's disease memory loss, was substantially reduced after treatment.Previous studies suggest that increased consumption of grape- derived polyphenols, whose content, for example, is very high in red wine, may protect against cognitive decline in Alzheimer's. This new finding corroborates those theories."Since naturally occurring polyphenols are also generally commercially available as nutritional supplements and have negligible adverse events even after prolonged periods of treatment, this new finding holds significant promise as a preventive method or treatment, and is being tested in translational studies in Alzheimer's disease patients," said Pasinetti.In Alzheimer's disease, brain cells degenerate and die, causing a steady decline in memory and mental function.

CANBERRA, Aug. 29 (Xinhua) -- An Australia report released on Monday draws a direct link between inaction on climate change and long-term social and mental health problems.The Climate Institute report, A Climate of Suffering: The Real Cost of Living with Inaction on Climate Change, points that in the wake of extreme weather in Australia, such as cyclones and droughts, there is an increase in depression, anxiety, post- traumatic stress and substance abuse.As many as one in five people reported "emotional injury, stress and despair" in the wake of these events.The report also warns continuing catastrophic weather events are creating anxiety and insecurity for children at levels not seen since the Cold War.It claims one in 10 children of primary school age showed symptoms of post-traumatic stress disorder after Cyclone Larry in 2006.According to Professor Ian Hickie, from the Brain & Mind Institute, regional and remote communities are most vulnerable to the impact of climate change.He said a recent study of rural New South Wales where, following the long drought, self-harm and suicide rose by up to eight percent."I think what we are seeing now is a much more significant counting of not just the short-term costs and reactions but the longer-term costs, the loss of community cohesion and that being essential to people's long-term mental health," Professor Hickie."The drought was a particularly instructive event for everyone in Australia and we saw a lot of focus for the first time on the mental health effects, particularly suicides in rural families, the effect on rural communities of prolonged examples of weather change," Hickie said.Climate Institute chief executive John Connor said that not only did natural disasters cost taxpayers about nine billion U.S. dollars last year, but there are also damaging Australia's social fabric.He said that with Australian regions increasingly exposed to extreme weather, recognizing and managing the risks of climate change is essential, and it is an insurance policy to protect Australia's communities.The study came as the political and social debate over Australian federal government's proposed carbon tax intensifies.In 2007, a report by the Commonwealth Scientific and Industrial Research Organization (CSIRO) projected the effects of various greenhouse gas emission scenarios for 2030, 2050 and 2070.It said droughts were likely to become more frequent, fire danger was set to increase and tropical cyclones were likely to become more intense.

WASHINGTON, July 27 (Xinhua) -- Astronomers studying observations taken by NASA's Wide-field Infrared Survey Explorer (WISE) mission have discovered the first known "Trojan" asteroid orbiting the sun along with Earth, the U.S. National Aeronautics and Space Administration (NASA) announced Wednesday in a statement.Trojans are asteroids that share an orbit with a planet near stable points in front of or behind the planet. Because they constantly lead or follow in the same orbit as the planet, they never can collide with it. In our solar system, Trojans also share orbits with Neptune, Mars and Jupiter. Two of Saturn's moons share orbits with Trojans.Scientists had predicted Earth should have Trojans, but they have been difficult to find because they are relatively small and appear near the sun from Earth's point of view."These asteroids dwell mostly in the daylight, making them very hard to see," said Martin Connors of Athabasca University in Canada, lead author of a new paper on the discovery to be published Thursday in the journal Nature. "But we finally found one, because the object has an unusual orbit that takes it farther away from the sun than what is typical for Trojans. WISE was a game-changer, giving us a point of view difficult to have at Earth 's surface."The WISE telescope scanned the entire sky in infrared light from January 2010 to February 2011. Connors and his team began their search for an Earth Trojan using data from NEOWISE, an addition to the WISE mission that focused in part on near-Earth objects, or NEOs, such as asteroids and comets. NEOs are bodies that pass within 28 million miles (45 million kilometers) of Earth 's path around the sun. The NEOWISE project observed more than 155, 000 asteroids in the main belt between Mars and Jupiter, and more than 500 NEOs, discovering 132 that were previously unknown.The team's hunt resulted in two Trojan candidates. One called 2010 TK7 was confirmed as an Earth Trojan after follow-up observations with the Canada-France-Hawaii Telescope on Mauna Kea in Hawaii.The asteroid is roughly 1,000 feet (300 meters) in diameter. It has an unusual orbit that traces a complex motion near a stable point in the plane of Earth's orbit, although the asteroid also moves above and below the plane. The object is about 50 million miles (80 million kilometers) from Earth. The asteroid's orbit is well-defined and for at least the next 100 years, it will not come closer to Earth than 15 million miles (24 million kilometers).

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