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WASHINGTON, July 20 (Xinhua) -- Using the Hubble Space Telescope, astronomers have discovered a fourth moon orbiting the icy dwarf planet Pluto, the U.S. National Aeronautics and Space Administration (NASA) announced Wednesday in a statement. The tiny, new satellite, temporarily designated P4, was uncovered in a Hubble survey searching for rings around the dwarf planet.P4 was first seen in a photo taken with Hubble's Wide Field Camera 3 on June 28. It was confirmed in subsequent Hubble pictures taken on July 3 and July 18. It is the smallest moon discovered around Pluto. It has an estimated diameter of 8 to 21 miles (13 to 34 km). By comparison, Charon, Pluto's largest moon, is 648 miles (1,043 km) across, and the other moons, Nix and Hydra, are in the range of 20 to 70 miles in diameter (32 to 113 km).Two labeled images of the Pluto system taken by the Hubble Space Telescope's Wide Field Camera 3 ultraviolet visible instrument with newly discovered fourth moon P4 circled. The image on the left was taken on June 28, 2011. The image of the right was taken on July 3, 2011."I find it remarkable that Hubble's cameras enabled us to see such a tiny object so clearly from a distance of more than 3 billion miles (5 billion km)," said Mark Showalter of the SETI Institute in California, who led this observing program with Hubble.P4 is located between the orbits of Nix and Hydra, which Hubble discovered in 2005. Charon was discovered in 1978 at the U.S. Naval Observatory and first resolved using Hubble in 1990 as a separate body from Pluto.The dwarf planet's entire moon system is believed to have formed by a collision between Pluto and another planet-sized body early in the history of the solar system. The smashup flung material that coalesced into the family of satellites observed around Pluto.The finding is a result of ongoing work to support NASA's New Horizons mission, scheduled to fly through the Pluto system in 2015. The mission is designed to provide new insights about worlds at the edge of our solar system. Hubble's mapping of Pluto's surface and discovery of its satellites have been invaluable to planning for New Horizons' close encounter."This is a fantastic discovery," said New Horizons' principal investigator Alan Stern of the Southwest Research Institute in Colorado. "Now that we know there's another moon in the Pluto system, we can plan close-up observations of it during our flyby."

SAN FRANCISCO, July 29 (Xinhua) -- Apple has ousted Nokia as the world's largest smartphone maker as global mobile phone market grew more than 11.3 percent in the second quarter of 2011, according to two separate market research studies.After becoming the largest smartphone vendor in terms of revenue and profits, Apple has become the world's largest smartphone vendor by volume with 18.5 percent market share, said the latest research from Strategy Analytics released on Friday.The Cupertino, California-based company sold 20.3 million iPhones in the second quarter,up 142 percent compared with the same period a year earlier.Samsung's shipments of 19.2 million units grew a huge 520 percent year over year, accounting for 17.5 percent global smartphone market share in the second quarter of 2011.Apple and Samsung overtook long-time volume leader Nokia for the two spots. The Finnish mobile phone giant accounted for 15.2 percent of global smartphone market share in the last quarter, which is less than half of what it was just one year earlier.In the second quarter of 2010, Nokia was the No.1 smartphone maker by volume in the world with 38.1 percent of market share. The industry is now waiting Nokia's pending transition to Windows Phone 7.According to a separate report by International Data Corporation (IDC) released on Thursday, the worldwide mobile phone market grew by 11.3 percent year over year in the second quarter of 2011 despite a decline of the feature phone market for the first time in almost two years.The feature phone market was down by 4 percent in the last quarter, said the IDC Worldwide Mobile Phone Tracker report. It noted that the decline in shipments was mainly in economically mature regions, such as the United States, Japan and Western Europe, as users making rapid transition to smartphones.The shrinking feature phone market had a great impact on some of the world's largest suppliers of mobile phones, such as Nokia, which is losing share in the feature phone category to low-cost suppliers, said the report.For the overall market, global mobile phone vendors shipped 365. 4 million units in the second quarter, compared to 328.4 million units in the same period last year, with Nokia still holding the top spot with a market share of 24.2 percent, followed by Samsung, LG Electronics, Apple and ZTE.But the 11.3 percent growth was lower than IDC's forecast for the quarter and also below the 16.8 percent growth in the first quarter of 2011.IDC said the feature phone forecast isn't expected to be any rosier in the future and the shipment growth of feature phones won 't exceed 1.1 percent in the coming years.

BEIJING, Aug. 5 (Xinhuanet) -- A study conducted by Israeli researchers at the Albert Einstein College of Medicine in New York shows that genes, rather than good eating and lifestyle habits, determine longevity, according to media reports Friday. "This study suggests that centenarians may possess additional longevity genes that help to buffer them against the harmful effects of an unhealthy lifestyle," said senior author Nir Barzilai, director of the Institute for Aging Research at Yeshiva University's Albert Einstein College of Medicine.The study involves 477 Ashkenazi Jews between the ages of 95 and 122, of whom 75 percent are women. According to the study, Ashkenazi Jews are chosen as subjects because they are more "genetically uniform than other populations, making it easier to spot gene differences that are present."The study also found that the long-lived Ashkenazi Jews drank slightly more and exercised less than their average counterparts. But Barzilai also warned: “Although this study demonstrates that centenarians can be obese, smoke and avoid exercise, those lifestyle habits are not good choices for most of us who do not have a family history of longevity.""We should watch our weight, avoid smoking and be sure to exercise, since these activities have been shown to have great health benefits for the general population, including a longer lifespan," He added.

KATHMANDU, Aug. 7 (Xinhua) -- Ban on smoking in public places will be enforced from Sunday with the Tobacco Control and Regulatory Act-2010 coming into effect.Those smoking in public places will be fined and civil servants will be liable to departmental action.Government offices, corporations, educational institutions, libraries, airports, public vehicles, orphanages, childcare centres, cinema halls, homes for the elderly, cultural centres, children's gardens, hotels, restaurants, resorts, girls' and boys' hostels, department stores, religious sites and industries have been designated no-smoking zones.Health Secretary Sudha Sharma said mass awareness campaign highlighting punishment will be carried out. She also said an inter-ministerial coordinating committee has been formed to enforce the law to ensure people's right to health. Pasting no- smoking notices at every public place will be mandatory.According to The Himalayan Times daily, the ban covers sale of tobacco products and single sticks within a 100-meter radius of educational and health institutions, children's homes, child care centers and home for elders.Anyone selling tobacco products to persons under the age of 18 years and pregnant women will be fined.The Act also prohibits advertising and sponsoring programs in the name of tobacco-related products through media. Offenders will be fined.The government's mass awareness campaign will cover the entire country to ensure effective implementation of the Act.

来源：资阳报