哈密附近男科医院那家比较好-【哈密博爱医院】,哈密博爱医院,哈密包皮就一定要切吗,哈密去哪里检查妇科,哈密怀孕后多久可以测出来,哈密男人勃起困难怎么治,哈密勃起障碍治方法,哈密现在割包皮手术费用

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.

BEIJING, Sept. 28 (Xinhua) -- China's top economic planner announced Wednesday that it will raise the minimum purchase prices for wheat from farmers in 2012 to boost grain output.The move "aims to protect farmers' enthusiasm to grow grains and further stimulate grain production," the National Development and Reform Commission (NDRC) said in a statement.The minimum purchase price for white wheat in the country's major wheat-producing areas will be increased to 102 yuan (16 U.S. dollars) per 50 kg, up 7 yuan from the 2011 price, said the NDRC.It said the minimum purchase prices for red and mixed wheat will both rise 9 yuan to 102 yuan per 50 kg next year.Wheat is one of China's major grains, which feeds its population of 1.3 billion people mainly with domestically-produced grains.A stable food supply is crucial to China's efforts to check inflation, as food prices account for about a third of the weighting in its consumer price index (CPI) calculation, a main gauge of inflation.China's CPI rose to a 27-month year-on-year high of 6.5 percent in July and weakened slightly to 6.2 percent in August.The country's grain output rose 2.9 percent last year to 546.41 million tonnes, marking the seventh consecutive year of output growth.The Ministry of Agriculture expects the output to reach a record high of 550 million tonnes this year.
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.
BEIJING, June 12 (Xinhua) -- A senior Chinese official has called the country's police to better serve the people when the Communist Party of China (CPC) is meeting the 90th founding anniversary.Zhou Yongkang, member of the Standing Committee of the Political Bureau of the CPC Central Committee, made the remark on Sunday evening in meeting with top 10 favorite police officers selected through a nationwide vote.The Ministry of Public Security (MOPS) and the China Central Television have jointly conducted My Favorite Police Officer Competition in the past eight years.This year's winners include 75-year-old detective Wu Guoqing, network security police officer Li Qing from Jiangsu Province, traffic police officer Wu Hao of Miao Nationality from Hunan Province, female SWAT team leader Pan Qin from Guizhou Province.Zhou said that this year's competition attracted more than 150 million online voters which means more and more people are supporting the activity, and all winners should cherish the honor and better serve the people on their own posts.The official called on police officers around the country to learn from the 10 favarite officers and other winners in the competition who have all made outstanding contribution to the security of the people and society.
来源:资阳报