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BEIJING, Oct. 18 (Xinhuanet) -- NASA recently unveiled its new rocket design, named Space Launch System (SLS), according to media reports.The rocket will make its first unmanned flight in 2017, and the flight with astronauts aboard won't happen until 2021, according to NASA's plan.The new rocket was 320 feet in length (the space shuttle was 184 feet on the launch pad), 5.5 million pounds in weight, and with the capacity of holding four astronauts at the top speed of 25,000 miles per hour, Washington Post reported Tuesday.Compared with space shuttle and other predecessors, the new rocket will aim for much farther destinations into the space with its most powerful engine ever built, according to the plan."We're investing in technologies to live and work in space, and it sets the stage for visiting asteroids and Mars," the NASA administrator Charles Bolden briefed the media at a news conference in Washington.NASA expected to devote 3 billion U.S. dollars a year to the effort, or a total of about 18 billion U.S. dollars over the next six years, said William Gerstenmaier, the agency’s associate administrator for human exploration.The current financial condition of U.S. may slow down the pace of progress, which will be much slower than NASA's Apollo heyday in the 1960s.

TEHRAN, Oct. 9 (Xinhua) -- Iran is going to launch domestically- built Navid satellite by Safir satellite launcher by the end of March 2012, the semi-official Mehr news agency reported on Sunday.Navid (promise) is a research satellite and is currently undergoing pre-launch tests, said the report without further details.In June, Iran put the Rasad (surveillance) satellite in the orbit to render images to the country.Iran put a satellite into orbit in 2009 and sent some small animals into space in 2010. It plans to send man into space by 2020.

BEIJING, Dec. 9 (Xinhua) -- Beijing has seen a declining trend in newly built ordinary apartments in the past 11 months of this year, said a report released by the Beijing Real Estate Association on Friday.That average price of 13,914 yuan (about 2,194.23 U.S. dollars) per square meter from January to November went down 6.3 percent from the yearly average housing price of 14,847 yuan per square meter in 2010, also the target set by the municipal government in attempting to control soaring house prices, said the report.It is expected that the real-estate market in Beijing will maintain the gradually declining trend. And the target of "a stable yearly price with a slight decline" will be smoothly reached, said Chen Zhi, secretary-general of the association.In November, first-time home buyers took up about 90 percent of housing consumers for the ninth month in a row, which means the government's measures to crowd out investing or speculative buying and meet the demands of conventional buyers are working, the report said.This year the government has repeatedly stressed its efforts to contain the runaway property market, through measures including tighter monetary policies, higher down payments, a ban on third-home purchases, price control targets and a trial property tax.

SHIJIAZHUANG, Dec. 3 (Xinhua) -- More than 3.48 million people in rural areas of north China's Hebei Province have been given access to safe drinking water this year, a local official said Saturday.Authorities in the province have invested more than 1.7 billion yuan (270 million U.S. dollars) so far in 2011 in building drinking water infrastructure, said Liang Jianyi, deputy director of the Hebei Provincial Department of Water and Resources.More than 32 million rural people in Hebei, especially in mountainous and coastal areas, had long suffered from unsafe water, with problems including high fluorine and alkaline contents, Liang said.From 2005 to 2010, the provincial authorities put almost 6 billion yuan into providing safe drinking water for 13 million rural residents, he added.

BEIJING, Nov. 22 (Xinhuanet) -- Women aged 40 to 49 are not recommended for routine mammography screening for breast cancer, said the new guidelines issued by the Canadian Task Force on Preventive Health Care in media reports Tuesday.The new guidelines are purposed to direct doctors on using mammography, MRI scans, clinical breast exams and breast self-exams. In principle, they pointed out, there is no need for women to take clinical breast exams and breast self examination if there are no signals for breast cancer.Below are the main points from the guidelines which need special attention from women with reasonable doubt on the matter:Women aged 40-49 who have lower risk for cancer should not take routine mammography because of the higher risk for overdiagnosis, overtreatment and false-positives;Women aged 50 to 69 years and aged 70 to 74 years should go for routine screening every two to three years;And there should be no routine clinical breast exams by doctors and no breast self-exams to screen for breast cancer.Dr. Marcello Tonelli, Chair of the Task Force and Associate Professor at the University of Alberta, remarked: "The main effect of screening is to produce patients with breast cancer from among healthy women who would have remained free of breast disease for the rest of their lives had they not undergone screening.""The best method we have to reduce the risk of breast cancer is to stop the screening program," he added, "This could reduce the risk by one-third in the screened age group, as the level of overdiagnosis in countries with organized screening programs is about 50 percent."

来源：资阳报