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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.

BEIJING, Aug. 24 (Xinhuanet) -- Facebook said it is overhauling its privacy settings to give members easier, more precise control over who sees posts, photos and other content over the vast social network.Starting Thursday, Facebook is rolling out new privacy tools that are placed with each piece of content, replacing options that are now buried in overall account settings.Privacy has been a consistently sticky problem for the Palo Alto firm, which has felt the heat from privacy advocates and government regulators. And recently, Facebook faced stiffer competition from Google's new Google+ social network, which was hailed for including a "circles" feature with easy-to-use privacy settings.Instead of vague labels such as "everyone," which have been mistaken for a Facebook member's social network instead of anyone on the Internet, the new system will include more precise words such as "public.""You have told us that 'who can see this?' could be clearer across Facebook, so we have made changes to make this more visual and straightforward," Chris Cox, Facebook's vice president of product, said in blog post."The main change is moving most of your controls from a settings page to being inline, right next to the posts, photos and tags they affect. Plus there are several other updates here that will make it easier to understand who can see your stuff (or your friends') in any context," Cox said.While privacy advocates reserved judgment until the new settings are actually released, they were optimistic the changes will benefit consumers."These changes do make me feel very confident in the direction that Facebook is going and the way they are thinking about privacy," said Erica Newland, policy analyst for the Center for Democracy & Technology in Washington, D.C.

JIUQUAN, Gansu, Aug. 18 (Xinhua) -- China's experimental orbiter SJ-11-04, which was launched by a Long March II-C rocket Thursday, failed to enter the designated orbit due to a malfunction of the rocket.The rocket experienced malfunction during the flight following its launch from Jiuquan Satellite Launch Center at 5:28 p.m. Beijing Time in northwest Gansu Province.The specific cause of the failure is being analyzed.

LOS ANGELES, July 5 (Xinhua) -- NASA's Juno spacecraft is 30 days away before its first launch window opens, the Jet Propulsion Laboratory (JPL) announced on Tuesday."One month from today, our first launch window opens at 11:34 a. m. EDT (8:34 a.m. PDT) and lasts 69 minutes," said Jan Chodas, Juno project manager from NASA's JPL in Pasadena, Los Angeles."Our primary launch period is 22 days long, and so if weather or other issues come up on Aug. 5, we have 21 more days to get Juno flying. Once we get Juno into space, it's a five-year cruise to Jupiter.""The launch window is the length of time allotted every day for an attempt to launch the spacecraft," said Chodas. "The launch period is the period of time in days when everything is in the right place to get your mission off to the right start."For a mission like Juno, getting everything in the right place includes considering the size of the rocket and spacecraft, where our home planet -- and in particular Juno's launch pad -- is pointed at any moment, and its location in space relative to other celestial objects like Juno's final target, Jupiter.Juno is scheduled to launch aboard a United Launch Alliance Atlas V rocket from pad 41-C at the Cape Canaveral Air Force Station, Florida.The solar-powered spacecraft will orbit Jupiter's poles 33 times to find out more about the gas giant's origins, structure, atmosphere and magnetosphere and investigate the existence of a solid planetary core.JPL manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio.The Juno mission is part of the New Frontiers Program managed at NASA's Marshall Space Flight Center in Huntsville, Alaska. Lockheed Martin Space Systems, Denver, built the spacecraft.

BEIJING, Aug. 22 (Xinhuanet) -- U.S. presidential candidate Rick Perry's controversial stem-cell treatment may inspire desperate patients to follow his lead while causing medical and legal concerns, according to media reports Monday.The Texas governor underwent a procedure on July 1 where stem cells, made from fat taken from his body, were put into his bloodstream to see if they might find their way to fix a bad back.The treatment carries potential risks ranging from blood clots to infection to cancer and may even run afoul of federal rules, doctors say. File photo of U.S. Republican presidential candidate Texas Governor Rick Perry."As a highly influential person of power, Perry’s actions have the unfortunate potential to push desperate patients into the clinic of quacks,” Harvard’s stem cell expert George Daley told the Associated Press.Worries about the safety and wisdom of this treatment are widespread among stem cell researchers as such a treatment has not been thoroughly vetted by researchers or approved by the FDA.

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