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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.

XIAMEN, July 23 (Xinhua) -- A rescue and breeding base for endangered Chinese white dolphins started a trial operational period on Saturday in the southeastern seaside resort of Xiamen. The base is the first of its kind in the country.The base, located on the city's Huoshaoyu Islet, includes a rescue center and a breeding area and can accommodate up to four to six white dolphins, said Pan Shijian, vice mayor of Xiamen.Previously, rescuers had to return injured white dolphins back to the sea after giving them simple medical treatment due to the lack of a rescue base, Pan said."From now on, the base will be a hospital for injured or stranded dolphins," he said.The base will also be used as a rehabilitation center for children with infantile autism and brain paralysis, with the dolphins acting as "doctors" during the children's recovery period, he added.The Chinese white dolphin mainly lives in the seas around Xiamen and the Pearl River estuary in south China. The dolphins are under first-class state protection.The Chinese Academy of Fishery Sciences estimates that about 2,000 of the dolphins are living in China's seas.

SINGAPORE, July 6 (Xinhua) -- A team of researchers in Singapore has designed a tube with special robotic hands that allows doctors to perform surgery on a patient's inner organs without resulting in scars, local media reported on Wednesday.The special "robotic hands" were fixed to the tube to access a patient's stomach. Compared with traditional methods which use only one robotic hand, the new device known as master and slave transluminal endoscopic robot, or MASTER, is more nimble, thereby allowing complex operations, the Lianhe Zaobao reported.Louis Phee, an associate professor at the Nanyang Technological University who led the team of researchers, had spent six years to develop the gadget, which cut an eight-hour procedure to just 17 minutes, said doctors at India's Asian Institute of Gastroenterology.The gadget, still in the trial stage, has been tested earlier this month on three patients at the Indian hospital. It is also expected to be tried out in Germany and China's Hong Kong later. The patients can leave the hospital much sooner than they would have using traditional gadgets.Phee said he expected the gadget to be available on the market as early as three years from now, after going through clinical trials and getting the approval from authorities.He also saw a potential for the gadget to be used on other organs by cutting a small spit on stomach that allows the gadget to go through to access the site.

TOKYO, June 19 (Xinhua) -- The Japanese gaming company Sega Corp. said in a statement on Sunday some personal information from more than 1.2 million registered users had been stolen after the website of its subsidiary based in Britain was hacked.The Sega Pass website operated by Sega Europe limited was designed to provide product news. The services were shutdown following the breach detected on Friday. They are still not resumed on the official website of the company late Sunday night and the company said it is investigating the hacking.The company said most of the users of the hacked website are in Europe and North America. A similar cyberattack had troubled the Sony group earlier in April. The hacking affected about 100 million people.

LOS ANGELES, July 22 (Xinhua) -- Two teams of astronomers have discovered the largest and farthest reservoir of water ever detected in the universe, NASA's Jet Propulsion Laboratory (JPL) said on Friday.The water, equivalent to 140 trillion times all the water in the world's ocean, surrounds a huge, feeding black hole, called a quasar, more than 12 billion light-years away, according to JPL in Pasadena, California."The environment around this quasar is very unique in that it's producing this huge mass of water," said Matt Bradford, a scientist at JPL. "It's another demonstration that water is pervasive throughout the universe, even at the very earliest times. "This artist's concept illustrates a quasar, or feeding black hole, similar to APM 08279+5255, where astronomers discovered huge amounts of water vapor. Gas and dust likely form a torus around the central black hole, with clouds of charged gas above and below. X-rays emerge from the very central region, while thermal infrared radiation is emitted by dust throughout most of the torus. While this figure shows the quasar's torus approximately edge-on, the torus around APM 08279+5255 is likely positioned face-on from our point of view.A quasar is powered by an enormous black hole that steadily consumes a surrounding disk of gas and dust. As it eats, the quasar spews out huge amounts of energy. Both groups of astronomers studied a particular quasar called APM 08279+5255, which harbors a black hole 20 billion times more massive than the sun and produces as much energy as a thousand trillion suns.Astronomers expected water vapor to be present even in the early, distant universe, but had not detected it this far away before. There's water vapor in the Milky Way, although the total amount is 4,000 times less than in the quasar, because most of the Milky Way's water is frozen in ice. Water vapor is an important trace gas that reveals the nature of the quasar. In this particular quasar, the water vapor is distributed around the black hole in a gaseous region spanning hundreds of light-years in size (a light-year is about six trillion miles).Its presence indicates that the quasar is bathing the gas in X- rays and infrared radiation, and that the gas is unusually warm and dense by astronomical standards, JPL said.Although the gas is at a chilly minus 63 degrees Fahrenheit ( minus 53 degrees Celsius) and is 300 trillion times less dense than Earth's atmosphere, it's still five times hotter and 10 to 100 times denser than what's typical in galaxies like the Milky Way, said JPL.Measurements of the water vapor and of other molecules, such as carbon monoxide, suggest there is enough gas to feed the black hole until it grows to about six times its size, JPL said.Whether this will happen is not clear, the astronomers say, since some of the gas may end up condensing into stars or might be ejected from the quasar.Bradford's team made their observations starting in 2008, using an instrument called "Z-Spec" at the California Institute of Technology's (Caltech's) Submillimeter Observatory, a 33-foot (10- meter) telescope near the summit of Mauna Kea in Hawaii. Follow-up observations were made with the Combined Array for Research in Millimeter-Wave Astronomy (CARMA), an array of radio dishes in the Inyo Mountains of Southern California.The second group, led by Dariusz Lis, senior research associate in physics at Caltech and deputy director of the Caltech Submillimeter Observatory, used the Plateau de Bure Interferometer in the French Alps to find water. In 2010, Lis's team serendipitously detected water in APM 8279+5255, observing one spectral signature.Bradford's team was able to get more information about the water, including its enormous mass, because they detected several spectral signatures of the water, according to JPL.