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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.

WASHINGTON, July 12 (Xinhua) -- Two U.S. astronauts stepped out the International Space Station on Tuesday to retrieve a failed ammonia pump, which is the last spacewalk of the shuttle era, NASA announced.Space station astronauts Mike Fossum and Ron Garan completed the six-hour, 31-minute spacewalk at 3:53 p.m. EDT (1953 GMT). The duo retrieved a pump module from an external stowage platform on station and store it in shuttle Atlantis' cargo bay for return to Earth.The pump module failed in 2010, shutting down half of the space station's cooling system. Engineers will evaluate the module to determine the cause of the failure and plan to refurbish it for use as a spare.The astronauts also attached a Robotic Refueling Module experiment to the space station, which aims to test technologies for repairing and refueling satellites in space.It was the 249th spacewalk by U.S. astronauts and the 160th spacewalk in support of space station assembly and maintenance, totaling 1009 hours, nine minutes.Atlantis lifted off on Friday morning from Kennedy Space Center in Florida, on the 135th and final flight in NASA's shuttle program. Its return to the earth later this month will mark the end of the 30-year shuttle program.

BEIJING, July 3 (Xinhuanet) -- The Atlantis mission to be launched by NASA on July 8 will not be an end to the space age, as some media suggest.Although it is the final mission of the space shuttle, it will open up "the next chapter" in the United States' space exploration, NASA's administrator Charles Bolden Jr said at the National Press Club in Washington on Friday."When I hear people say - or listen to media reports - that the final shuttle flight marks the end of US human space flight, I have to say . . . these folks must be living on another planet," he said."As a former astronaut and the current NASA administrator, I'm here to tell you that American leadership in space will continue for at least the next half-century because we have laid the foundation for success - and for NASA, failure is not an option," he said.NASA administrator Charles Bolden Jr drew a lot of media attention during his speech at the National Press Club in Washington DC.One of the foundations is the "unprecedented" research capabilities the International Space Station (ISS) now possesses, largely thanks to the space shuttle missions.Although some media imply that "the game will be up" once the ISS is out of orbit in 2020, he said the splendid research results and rich knowledge astronauts and scientists have accumulated through more than 1,200 experiments since 1998 have laid out "a stepping-stone to the rest of the solar system and the tip of what comes next".As NASA turns a new page, it will "focus on deep space exploration", while leaving US private companies to operate low Earth orbit transportation systems for tourism and business, he said.NASA will develop "a deep space crew vehicle and an evolvable heavy-lift rocket," he said. The moon, asteroids and Mars will be the next destinations for humans to live and work, he said."We will maintain and grow US leadership in space and derive all the benefits that flow from it. Tomorrow's space program is taking shape right now," he said.

CANBERRA, Aug. 29 (Xinhua) -- Alzheimer Australia on Monday released a GPS device for people with dementia, in a move to give them greater independence, while reducing the burden of missing person searches for police.The technology has been using in New South Wales of Australia, and is now available for people in state Victoria.The Safe2Walk locater can be worn by people with dementia on a lanyard around the neck or clipped onto a belt. Families can log- on to the connected website and see where the person is.The device updates the person's location every 60 seconds, reducing stress for carers so they know when a person with dementia might be wandering.It also works as a mobile phone, letting the person wearing the device to make instant calls to family.According to Alzheimer's Australia's research manager Jason Burton, the device aimed to stop vulnerable people getting lost, with research showing about 40 percent of people with dementia went missing at least once."In 99 percent of cases the carer has gone to pick them up, but there was one case where they couldn't and the police were able to contact us to get the exact GPS location of this person to rescue them," Burton told Herald Sun.A Victoria Police spokeswoman said while it could not endorse a specific product, if the device could alert carers when a person with dementia first became disorientated, the response could help avoid a large-scale police search.Mina Sapounakis, who's father has worn the Safe2Walk device, said it has given her family a sense of calm."We could go grocery shopping without stressing and rushing back home quickly to check on Dad," she said."There were a few times he had gone wandering and we were able to easily find him without having to call the police."The Safe2Walk GPS costs under 15 U.S. dollars a week for rent.

XICHANG, Sichuan, July 12 (Xinhua) -- China blasted off a new data relay satellite "Tianlian I-02" on Monday at the Xichang Satellite Launch Center in southwest Sichuan Province .The satellite was launched on a Long March-3C carrier rocket at 11:41 p.m. (Beijing Time), said sources with the center.Developed by the China Academy of Space Technology under the China Aerospace Science and Technology Corporation, the satellite is the country's second data relay satellite.China launched its first data relay satellite "Tianlian I-01" on April 25, 2008.The two satellites will form a network to offer data relay and measurement and control service for China's spacecrafts and planned space stations, according to the center.They will also be used to help perform the nation's first space docking, scheduled for the second half of 2011.China plans to launch Tiangong-1 and Shenzhou-8 spacecraft in the latter half of this year, and they will perform the nation's first space docking.Monday's launch is the 140th mission of China's Long March series of rockets.

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