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WASHINGTON, July 7 (Xinhua) -- Space shuttle Atlantis will soar into the sky Friday on NASA's 135th and final flight. Its scheduled return to Earth later this month will mark the end of NASA's 30-year space program.Since its onset with the launch of space shuttle Columbia, the program has been seen as a cheap, safe and reliable way for space exploration.Despite its great contributions to U.S. manned space flight, it has also left some grave and tragic lessons, making its termination inevitable.HIKING COSTSLaunched in 1972 by then President Richard Nixon, the shuttle program aimed to provide a new system of affordable space travel and proved to be NASA's most enduring project in its 50 years of existence.In 1981, shuttle Columbia made its first shuttle flight for two days. It was the ultimate hybrid and the first reusable spacecraft.Launched like a rocket and gliding back to Earth like an airplane, space shuttles not only can act as a space taxi to carry astronauts, but have the muscle of a long-distance trucker to haul heavy machinery.The spaceship boasts more than 3,500 subsystems and 2.5 million parts and is nine times faster than a speeding bullet as it climbs heavenward. That versatility, however, has translated into higher costs.NASA originally estimated the program would cost about 90 billion U.S. dollars. However, its actual cost stands at about 200 billion dollars, compared with the 151 billion dollars spent on Apollo which took Americans to the moon in 1969.In an article in Technology Review, John Logsdon, former head of the Space Policy Institute at George Washington University, drew a direct connection between the ravenous shuttle budget and the lack of other large advances in manned space flight."By operating the system for 30 years, with its high costs and high risk, rather than replacing it with a less expensive, less risky second-generation system, NASA compounded the original mistake of developing the most ambitious version of the vehicle," he wrote."The shuttle's cost has been an obstacle to NASA starting other major projects," he added.HIGH RISKIn terms of safety, the shuttles have never been as reliable as their designers had envisioned.On average, one out of every 67 flights ended up with fatal accidents. Based on the rate of deaths per million miles traveled, the space shuttle is 138 times riskier than a passenger jet.Seven astronauts onboard died when Challenger exploded about a minute after launch in 1986. Nearly two decades after the tragic blast, a new catastrophe descended when the shuttle Columbia disintegrated moments before landing in 2003, killing another seven spacemen.Again, the shuttle program was shelved for more than two years as NASA stepped up efforts to make it safer. But experts say the fundamental problem related to shuttles' safety cannot be solved due to their "birth defects.""It is in the nation's interest to replace the Shuttle as soon as possible," concluded the panel that investigated the 2003 Columbia accident.

BEIJING, Sept. 14 (Xinhuanet) -- Facebook unveiled a new feature called "smart lists" on Tuesday, giving its users an easier way to share photos, posts and updates with smaller groups of friends.The new function, which commences on Wednesday, borrows from the success of the Circles feature of Google+, which allows users to categorize friends into groups.With the new feature, Facebook can automatically put your friends into groups, with the first four being work, school, family and city, based on the information of colleges, workplaces and geographic locations in users' profiles.The feature is optional to use, and the lists are customizable."This is really something we have been working on for four years," Facebook director of product management Blake Ross told AFP, adding "We think this is the way people will make lists going forward."In the meantime, the social networking site has also come up with "close friends" and "acquaintances" options.People can read the updates of their "close friends" more prominently in their news feed and just big news of their "acquaintances", according to Naomi Gleit, the director of product at Facebook who worked on the new feature.

LOS ANGELES, July 19 (Xinhua) -- Obesity prevalence was 30 percent or higher in 12 states of the United States last year, compared to nine states in 2009, the Centers for Disease Control and Prevention (CDC) said on Tuesday.In 2000, no states in the country had obesity rates that high, and now obesity is a problem in all 50 states, the agency said in a report based on telephone interviews with 400,000 people.Obesity rates vary by region, led by the South at 29.4 percent, followed by the Midwest at 28.7 percent, the Northeast at 24.9 percent, and the West at 24.1 percent, the report said.Mississippi had the nation's highest obesity prevalence at 34 percent, and Colorado the lowest at 21 percent, according to the report.Alabama, Arkansas, Kentucky, Louisiana, Michigan, Mississippi, Missouri, Oklahoma, South Carolina, Tennessee, Texas, and West Virginia all had obesity rates of 30 percent or higher in 2010, said the report.No state met the federal Healthy People 2010 goal of a 15 percent obesity rate. In fact, no state had a rate lower than 20 percent, the CDC said.Obesity rates have kept rising despite a steady drumbeat of warnings that obesity causes serious health problems and increases the risk of premature death, CDC officials said.An adult is considered obese if he or she has a body mass index (BMI) of 30 or greater.

SINGAPORE, June 14 (Xinhua) -- Researchers from Singapore and China are conducting a research aimed at using different technologies to completely capture and convert carbon dioxide in industrial emissions into energy, local daily Lianhe Zaobao reported on Tuesday.The project, supported by the National Research Foundation (NSF) of Singapore, will make use of sunlight as well as photochemical and photosynthetic processes, the foundation said.The researchers involved in the five-year project are from China's Peking University and Singapore's National University of Singapore and the Nanyang Technological University. A research center will be established under the Campus for Research Excellence and Tehnological Enterprise, a program also known as CREATE, the foundation said.It will be the first project involving cooperation with a Chinese university under the program. It will be located at the University Town of the National University of Singapore due to be completed by the end of the year.Lee Yuan-Kun, a researcher at the National University of Singapore, said no single chemical process can capture and convert the carbon dioxide completely so the researchers will be first treating the emissions with photochemical and electrochemical processes to convert most of the carbon dioxide into energy resources such as methane.The gas with thinner carbon dioxide will then be used to grow microalgae, he said.Nevertheless, for the cost of renewable energy to be close to that of fossil fuel, the efficiency will have to be drastically improved by about five to 10 times, Lee said.The project is one of three energy research projects to be housed under the Campus for Research Excellence and Tehnological Enterprise program.Zhang Dongxiao, from the College of Engineering at Peking University, said that the research program seeks to develop energy efficient and environmentally friendly carbon capture technologies that can be applied in the manufacturing and chemical industries, and that it complements Peking University's strong capability in carbon storage."Reducing carbon intensity will not only benefit both countries in terms of cost competitiveness of products made, but also portrays a good image on our national responsibility to achieve a sustainable Earth," Zhang said.