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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, June 20 (Xinhua) -- Google and the British Library announced Monday that the Internet search giant will digitize 250,000 out-of-copyright books from the library's collections, making up to 40 million pages from 1700 to 1870 available to the public online.In a joint statement, the British Library and Google said they will work in partnership over the coming years to deliver the content free through Google Books and the library's website, and full text search, download and reading will be available. Google will cover all digitization costs.The project is going to cover a huge range of printed books, pamphlets and periodicals dated 1700 to 1870, a period of political and technological turmoil, from the Industrial Revolution to the French Revolution, from the introduction of the income tax in Britain and the invention of the telegraph and railway.It will include material in a variety of major European languages and will focus on books that are not yet freely available in digital form online, said the statement.Since December 2004, Google has announced partnership with some 40 high-profile university and public libraries, planning to digitize and make available some 15 million volumes within a decade through Google Books service.The project has triggered controversy as publisher and author associations oppose the plan to put copyrighted titles online in a class action lawsuit.

WASHINGTON, July 10 (Xinhua) -- U.S. space shuttle Atlantis docked with the International Space Station on Sunday morning after nearly two days of flight.Commander Christopher Ferguson guided space shuttle Atlantis to a docking with the station at 11:07 a.m. EDT (1507 GMT) when the two spacecrafts were flying 240 miles up over east of New Zealand, according to NASA.This was the 12th and final time Atlantis docked to the space station. It was the 46th shuttle docking to a space station, nine to the Russian Mir station and 37 to the International Space Station.The space shuttle Atlantis is seen with part of the structure of the International Space Station in the foreground and the earth in the background as it approaches the station for docking in this still image from NASA TV July 10, 2011. The shuttle and station crews will open hatches and hold the traditional welcome ceremony at about 1:19 p.m. EDT (1719 GMT). The combined crew of 10 will begin more than a week of docked operations, transferring vital supplies and equipment to sustain station operations once the shuttles are retired.Atlantis lifted off on Friday morning from Kennedy Space Center in Florida, on the 135th and final flight in NASA's shuttle program.It is the 33rd voyage for Atlantis. Its return to the earth later this month will mark the end of the 30-year shuttle program.

WASHINGTON, Aug. 31 (Xinhua) -- Astronomers using NASA's Chandra X-ray Observatory discovered the first pair of supermassive black holes in a spiral galaxy similar to the Milky Way, NASA announced Wednesday.Approximately 160 million light years from Earth, the pair is the nearest known such phenomenon.The black holes are located near the center of the spiral galaxy NGC 3393. Separated by only 490 light years, the black holes are likely the remnant of a merger of two galaxies of unequal mass a billion or more years ago.Both of the supermassive black holes are heavily obscured by dust and gas, which makes them difficult to observe in optical light. Because X-rays are more energetic, they can penetrate this obscuring material. Chandra's X-ray spectra show clear signatures of a pair of supermassive black holes."If this galaxy weren't so close, we'd have no chance of separating the two black holes the way we have," said Pepi Fabbiano of the Harvard-Smithsonian Center for Astrophysics, who led the study that appeared Wednesday in on-line issue of the journal Nature. "Since this galaxy was right under our noses by cosmic standards, it makes us wonder how many of these black hole pairs we've been missing."Previous observations in X-rays and at other wavelengths indicated that a single supermassive black hole existed in the center of NGC 3393. However, a long look by Chandra allowed the researchers to detect and separate the dual black holes. Both black holes are actively growing and emitting X-rays as gas falls towards them and becomes hotter.When two equal-sized spiral galaxies merge, astronomers think it should result in the formation of a black hole pair and a galaxy with a disrupted appearance and intense star formation. A well-known example is the pair of supermassive black holes in NGC 6240, which is located about 330 million light years from Earth.However, NGC 3393 is a well-organized spiral galaxy, and its central bulge is dominated by old stars. These are unusual properties for a galaxy containing a pair of black holes.

BEIJING, July 1 (Xinhuanet) -- China must adopt a holistic approach to addressing food safety challenges connected to the risk of contracting infectious diseases from contact with animals, the World Health Organization (WHO) has said. Peter Ben Embarek, food safety officer at WHO's China office, said the country faces risks connected to the need to produce more meat, eggs and milk to feed its growing population. He said the increased production will ramp up the risk of people being infected by food-borne diseases because of poor slaughtering oversight and the absence of proper surveillance and inspection systems. About 50 percent of pigs in China are slaughtered outside of formal facilities without the inspection of veterinarians or food safety officers. He said poorly trained producers have little or no awareness of food safety or the risk of animal diseases being passed on to humans. Such an environment could lead to the emergence of a new pandemic of influenza. During the past 60 years, 30 percent of the 335 new infectious diseases worldwide were transmitted through food, he said. Yet in many parts of China, public awareness remains low about such things. Xu Aixiang, a 35-year-old resident of Rizhao city in Shandong province, prefers to buy live poultry at local markets. Like many of her neighbors, she takes the chickens she buys home to slaughter them. "I get fresher chickens that are better quality this way," she said. "When vendors sell slaughtered chickens, the meat is no longer fresh and may have had water injected into it to make it heavier." But Ben Embarek cautioned that such live-animal markets are high-risk places for the exchange of viruses and diseases between animals and humans. He said simple and cost-effective measures can be taken to improve such markets' hygiene standards, such as the installation of separate areas to keep live poultry away from customers as well as improving air flow and waste management. Several UN agencies, including the WHO and the Food and Agriculture Organization, called on China to adopt an integrated approach to preventing emerging epidemic diseases and maintaining ecosystem integrity at an event themed "One Health" that convened on Wednesday in Beijing. At the gathering, representatives from the Ministry of Health, the Ministry of Agriculture and the Chinese Center for Disease Control and Prevention shared experiences from efforts to mitigate the H5N1 and H1N1 influenza outbreaks in China and said they were committed to working together in the future. Su Jingliang, an associate professor of preventive veterinary medicine at China Agricultural University, said his lab had detected the outbreak of a new type of flavivirus in ducks that led to a significant fall in egg production at farms in Beijing as well as in Hebei, Jiangxi and Shandong provinces. The pandemic was brought under control in March. No cases of humans contracting the disease have been reported so far but Su said he was concerned about the possibility of farmers becoming infected through close contact and long exposure to sick ducks. He said precautionary measures should be taken in cooperation with the Ministry of Health and other government agencies and checks should be run on people who are at high risk. Xu Wei contributed to this story.