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LOS ANGELES, June 9 (Xinhua) -- The edge of our solar system may not be smooth, but filled with a turbulent sea of magnetic bubbles approximately 100 million miles (160 million kilometers) wide, NASA's Jet Propulsion Laboratory (JPL) said on Thursday.The finding was based on observations from NASA's Voyager spacecraft, humanity's farthest deep space sentinels, said JPL in Pasadena, Los Angeles.While using a new computer model to analyze Voyager data, scientists found the sun's distant magnetic field is made up of bubbles which are created when magnetic field lines reorganize, said JPL.The new model suggests the field lines are broken up into self- contained structures disconnected from the solar magnetic field, according to JPL."The sun's magnetic field extends all the way to the edge of the solar system," said astronomer Merav Opher of Boston University. "Because the sun spins, its magnetic field becomes twisted and wrinkled, a bit like a ballerina's skirt. Far, far away from the sun, where the Voyagers are, the folds of the skirt bunch up."Like Earth, our sun has a magnetic field with a north pole and a south pole. The field lines are stretched outward by the solar wind, a stream of charged particles emanating from the star that interacts with material expelled from others in our corner of the Milky Way galaxy.Understanding the structure of the sun's magnetic field will allow scientists to explain how galactic cosmic rays enter our solar system and help define how the star interacts with the rest of the galaxy.The Voyager spacecraft, more than nine billion miles (14 billion kilometers) away from Earth, are traveling in a boundary region. In that area, the solar wind and magnetic field are affected by material expelled from other stars in our corner of the Milky Way galaxy.Launched in 1977, the Voyager twin spacecraft have been on a 33- year journey. They are en route to reach the edge of interstellar space. JPL built the spacecraft and continues to operate them.

VIENNA, Sept. 22 (Xinhua) -- Climate change and rising temperature in the long term can lead to water shortages in the Alps region, international experts warned Thursday at the Water-Scarce Final Conference in the Austrian eastern city Graz.The Alpine region originally is rich in water resources due to a large number of glaciers, spring and abundant rainfall either in summer or winter. But global warming may change this situation which has been shown in the past years that the water reserve has reduced gradually due to climate change, warned the experts.Observation data have shown a significant decrease of 25 percent in groundwater recharge in the past 100 years which has also resulted in the reduction of mountain spring.Director of the Provincial Department of Water Resources of Styria Johann Wiedner point out, in 2003, droughts occurred in the eastern part of the Alps, including the state of Styria and water shortages were also found in other regions of the Alps. He said the phenomenon was giving a warning that people "have to do something."To this end, the European Union begun a project called "Alp Water Scarce" three years ago to observe water reserves, air temperature, water temperature and water table in this region and study the relationships among them.Wiedner also admitted that there is no shortage of water at least in the short term and water supply for the local residents is totally insured.

PHNOM PENH, Aug. 17 (Xinhua) -- The critically endangered Irrawaddy dolphin population in the Mekong River numbers just 85, World Wildlife Fund (WWF) new research revealed on Wednesday.Calf survival was found to be very low, leading researchers to conclude that the small population is declining and at high risk of extinction, said the Fund's statement sent to Xinhua News Agency on Wednesday.According to Li Lifeng, Director of WWF's Freshwater Program, the research is based on photographic identification of dolphins through individually unique features of their dorsal fins. "Most of the dolphins can be identified, and we use that information to estimate the population size," he said.Although this population estimate is slightly higher than the previous estimate, the researchers were quick to note that the population had not increased over the last few years."With a larger dataset and recent analytical advances, previously unidentifiable dolphins which had few marks on their dorsal fins have been included," he added.However, surveys conducted from 2007 to 2010 show the population slowly declining."Evidence is strong that very few young animals survive to adulthood, as older dolphins die off and are not replaced," he explained."Pressures of gill net entanglement and high calf mortality we are really worried for the future of dolphins," Li said.However, Touch Seang Tana, chairman of Cambodia's Commission for Conversation and Development of the Mekong River Dolphins Eco- tourism Zone, rejected the WWF's finding, saying that last year, 4 dolphins were killed by fishing nets, but up to 7 newborn dolphin babies were found.He estimated that the total population of Mekong dolphins in the north-eastern provinces of Kratie and Stung Treng is between 155 and 177 now, up from just 100 in 2006.The Mekong River Irrawaddy dolphin has been listed as critically endangered on the World Conservation Union Red List of Threatened Species since 2004.

PARIS, June 14 (Xinhua) -- Solar Impulse, a Swiss solar-powered aircraft, finally arrived in Paris on Tuesday after three days' delay, ready for a debut at the biennial International Paris Air Show.The 1.6-ton solar-powered plane was expected to land in Paris on Saturday but technical problems and bad weather forced it to turn back to Brussels.The plane took its first international flight from Switzerland to Brussels on May 13 and then marked its second international flight to Paris. It has 12,000 solar cells mounted on the wings, which provide momentum for its four electric motors.Solar Impulse is the first aeroplane designed to fly day and night without requiring fuel and without producing carbon emission. The 64-meter-wingspan (as wide as an Airbus A340) can fly at extremely slow speed and has a weight equivalent to that of an average family car.Regarded as a "special guest" in the show, Solar Impulse made a historic 26-hour day and night flight without fuel in July 2010.During the Paris air show from 20 to 26 June, visitors can enjoy a close look at the innovative plane on ground every day and if weather condition permits, flying displays will take place.According to Paris Air Show organizers, 59 of the top 100 companies in the air industry worldwide will be present. More than 1,800 small and medium-sized companies will be exhibiting their products during the one-week show. Enditem

SAN FRANCISCO, Sept. 9 (Xinhua) -- AOL's chief executive officer (CEO) Tim Armstrong has reached out to Yahoo for talks of a merger of the two companies, U.S. media reported on Friday.Armstrong is discussing options for a combination aimed at strengthening the two Internet companies, Bloomberg quoted two people who are familiar with the matter as saying.The report said that the AOL CEO had been interested in a merger with Yahoo last year but was rejected while Carol Bartz served as Yahoo CEO, who was ousted by Yahoo's board on Tuesday.Reconsidering the option after Bartz's departure, Armstrong has talked with private equity firms and investment bankers from Allen & Co. working with Yahoo.Under one scenario being considered, Yahoo would acquire AOL and Armstrong would become CEO of the combined company, said the source.Both Yahoo and AOL are suffering from declining revenues, struggling to compete against companies like Google and Facebook. Some analysts said that the merger could not provide a long-term solution to the problems the two companies face after they failed to keep up with Internet trends.