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BEIJING, Sept. 23 (Xinhua) -- A defunct U.S. satellite is expected to crash down to Earth Friday, with nobody knowing where or when exactly it will hit. This was avoidable, a Chinese expert said Thursday.Pang Zhihao, a researcher from the Chinese Research Institute of Space Technology, told Xinhua that the crash could have been avoided had the satellite been put into a higher orbit, or manipulated to drop in the South Pacific when it had abundant fuel. It would pose no threat to Earth if these measures had been taken.NASA's tumbling, 5,900 kg Upper Atmosphere Research Satellite, or UARS, is the first of such man-made space vehicles that have been launched into outer space according to the agency's Mission to Planet Earth. The mission was launched in the 1990s.The mission is designed to provide data for better understanding Earth's upper atmosphere and the effects of natural and human interactions on the atmosphere.The satellite was deactivated in 2005 as it ran out of fuel and was left orbiting Earth like a big piece of space junk.There are other cases of defunct satellites. The European Space Agency said earlier its observation satellite ERS-2 has run out of fuel and is deorbiting. It would therefore also crash sooner or later.Pang said all countries which are operating space vehicles should take care of their own spacecrafts so that they won't pose any danger.The expert also said that the public need not worry too much.Pang said most spacecrafts will be incinerated upon re-entering Earth's atmosphere, and the debris will mostly likely fall into the ocean or hit an uninhabited area. In addition, a debris tracker is able to give a comparatively accurate prediction where the craft will fall about two hours before it hits Earth, giving residents, if there are any, time to evacuate.He added that there are several ways to minimize the threat of decommissioned spacecrafts, like putting them into higher orbits and crashing them into designated waters.Scientific progress would possibly bring about more ways of dealing with tumbling satellites. Scientists have already been trying to build spacecrafts with degradable materials so that they can self-destruct when re-entering Earth's atmosphere.

WASHINGTON, Aug. 31 (Xinhua) -- Astronomers using NASA's Chandra X-ray Observatory discovered the first pair of supermassive black holes in a spiral galaxy similar to the Milky Way, NASA announced Wednesday.Approximately 160 million light years from Earth, the pair is the nearest known such phenomenon.The black holes are located near the center of the spiral galaxy NGC 3393. Separated by only 490 light years, the black holes are likely the remnant of a merger of two galaxies of unequal mass a billion or more years ago.Both of the supermassive black holes are heavily obscured by dust and gas, which makes them difficult to observe in optical light. Because X-rays are more energetic, they can penetrate this obscuring material. Chandra's X-ray spectra show clear signatures of a pair of supermassive black holes."If this galaxy weren't so close, we'd have no chance of separating the two black holes the way we have," said Pepi Fabbiano of the Harvard-Smithsonian Center for Astrophysics, who led the study that appeared Wednesday in on-line issue of the journal Nature. "Since this galaxy was right under our noses by cosmic standards, it makes us wonder how many of these black hole pairs we've been missing."Previous observations in X-rays and at other wavelengths indicated that a single supermassive black hole existed in the center of NGC 3393. However, a long look by Chandra allowed the researchers to detect and separate the dual black holes. Both black holes are actively growing and emitting X-rays as gas falls towards them and becomes hotter.When two equal-sized spiral galaxies merge, astronomers think it should result in the formation of a black hole pair and a galaxy with a disrupted appearance and intense star formation. A well-known example is the pair of supermassive black holes in NGC 6240, which is located about 330 million light years from Earth.However, NGC 3393 is a well-organized spiral galaxy, and its central bulge is dominated by old stars. These are unusual properties for a galaxy containing a pair of black holes.

GENEVA, Aug. 10 (Xinhua) -- In a bid to prevent millions of deaths and suffering every year from malnutrition, the Geneva-based World Health Organization (WHO) launched an online initiative on Wednesday.The e-Library of Evidence for Nutrition Actions (eLENA), according to WHO, offers the latest advice on tackling the three main forms of malnutrition, including undernutrition, vitamin and mineral deficiencies, as well as overweight and obesity.The recommendations by eLENA to tackle malnutrition include promoting breastfeeding and fortifying staple foods with vitamins and minerals such as iron and folic acid for wheat and maize flours.It also recommends using multiple micronutrient powders to fortify foods for children aged between six and 23 months.To prevent anaemia, daily iron and folic supplements are advised for pregnant women, and intermittent iron and folic acid supplementation is recommended for menstruating women and preschool and school-age.While overweight and obesity affect around 1.5 billion adults over age 20, and more than 40 million children aged under five across the world, underweight is the leading risk factor for many diseases in low-income countries and represents about six percent of the world medical burden, WHO statistics showed.

BEIJING, Aug. 21 (Xinhuanet) -- The 7th Beijing-Tokyo Forum opened in Beijing on Sunday.This year’s forum, the Future of Asia and China-Japan Cooperation in Economic Reshaping, expects about 600 leaders from the political, business, academic and media fields to take part in a two-day discussion focusing on China-Japan cooperation.Wang Chen, minister of the State Council Information Office, delivers a speech at the reception for Beijing-Tokyo Forum on Saturday night in Beijing.Wang Chen, minister of the State Council Information Office, said at the reception on Saturday for the forum that China pursues an open development that is not exclusive to the rest of the world, but instead ensures cooperation and win-win with other countries."China and Japan’s economy are highly reliant on each other, and they are so close that they cannot get separated from each other,” Wang said.

COPENHAGEN, May 29 (Xinhua) -- The number of confirmed E.coli cases has risen to 11 with at least another eight persons suspected of having the intestinal infection in Denmark, according to Denmark's National Serum Institute on Sunday.Five of the confirmed cases show symptoms of kidney failure which marks an advanced stage of the sickness, the institute said.Danish cucumbers are suspected of helping spread the E. coli bacteria believed to be causing a deadly outbreak of intestinal infection in Denmark and Germany, local media reported Sunday.The Danish cucumbers were mixed in Germany with cucumbers originating in the Netherlands, making it difficult to determine if Danish cucumbers are in fact contaminated.Denmark's Veterinary and Food Administration (DVFA) had earlier said the suspicion against Danish cucumber was "vague", but advised Danish consumers not to eat raw tomatoes, lettuces and cucumbers from Germany, and cucumber from Spain.It is now checking Danish cucumbers for traces of E. coli with results expected on Tuesday.Some Danish retailers have now removed these products from their supermarket shelves. And the Danish branch of fast-food chain McDonald's announced Saturday that it was dropping fresh cucumbers from its menu until further notice.The infection, which is food-borne, can be caused by eating raw or uncooked foods such as vegetables contaminated with the E. coli bacteria.Symptoms of infection include mild fever, bloody diarrhea and vomiting, and can last five to seven days. It can prove fatal in the very young, sick, or elderly.

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