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WASHINGTON, Aug. 12 (Xinhua) -- NASA announced Friday the creation of a new directorate that will focus on both the International Space Station operations and human exploration beyond low earth orbit.The Human Exploration and Operations Mission Directorate combines the Space Operations and Exploration Systems mission directorates. While the transition and personnel assignments will take several weeks to finalize, the directorate already is supporting space station operations. It also will manage commercial crew and cargo developmental programs; construction of the Orion Multipurpose Crew Vehicle, a spacecraft designed to travel beyond low Earth orbit; development of a new heavy lift rocket, known as the Space Launch System; and other programs within the directorates."America is opening a bold new chapter in human space exploration," NASA Administrator Charles Bolden said in a statement. "By combining the resources of Space Operations and Exploration Systems, and creating the Human Exploration and Operations Mission Directorate, we are recommitting ourselves to American leadership in space for years to come."Associate Administrator Bill Gerstenmaier will head the new organization. He previously served as the associate administrator for Space Operations.

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, June 28 (Xinhuanet) -- A truck-sized asteroid passed over the Atlantic Ocean within 7,500 miles of the Earth on Monday, according to NASA's Jet Propulsion Laboratory.The space rock, called asteroid 2011 MD, is the second space rock to zip extremely close to the Earth this year.The asteroid, with latest size estimates ranging from 16 to 66 feet (5 to 20 meters) wide, was discovered just last week on June 22, but there was never any risk of it impacting the Earth, NASA scientists said. That means asteroid 2011 MD would likely be too small to survive the fiery plunge through the Earth's atmosphere, let alone reach the surface, NASA scientists said. Asteroids this size can be expected to buzz Earth with close shaves about once every six years, they added.The space rock flew well below geosynchronous satellites, which orbit 22,236 miles (35,786 km) above the Earth, but well above the 220-mile (354-km) altitude of the International Space Station.There was little chance that the asteroid would hit a satellite because of the vastness of space and relatively small number of satellites, experts said.

BEIJING, July 26 (Xinhuanet) -- The breast cancer is more deadly to black women than to whites, a new study found.This finding was published online Monday on the "Journal of Clinical Oncology" in the United States.The study was done by the City of Hope, a Comprehensive Cancer Center in Duarte, California.The researchers collected data from more than 4,500 U.S. women in the 35-64 age group who were diagnosed with breast cancer.With the passing of  more than eight years, the researchers found the black women have a three times death rate than white women, after taking obesity and other diseases into account."It’s been long known that breast cancer in African-American women is a far less common disease than in white women. But when it occurs, it seems to be more aggressive and harder to treat," said Dr. Lisa Carey of the University of North Carolina’s Lineberger Comprehensive Cancer Center.But why the situations varied by race, scientists are still exploring the answer.

BEIJING, Aug. 22 (Xinhuanet) -- Researchers have discovered how a human egg captures an incoming sperm for fertilization, paving the way to help couples suffering from infertility, according to media reports on Monday.An international team of researchers found that a sugar chain known as the sialyl-lewis-x sequence (SLeX) makes the outer coat of the egg “sticky,” which has proven to be helpful in binding the egg and the sperm.As a result, this observation has filled in a huge gap in the understanding of fertility and provides hope for ultimately helping couples who currently cannot conceive.Scientists and doctors know that a sperm identifies an egg when proteins on the head of the sperm match and bind to a series of specific sugars in the egg’s outer coating. With a successful match of proteins, the outside surfaces of the sperm and egg then bind together before merging, which is then followed by delivery of sperm’s DNA into egg.To identify this molecules, the researchers used ultra-sensitive mass-spectrometric imaging technology to observe and identify which molecules are most likely to be key in the binding process.They experimented with a range of synthesised sugars in the laboratory and found that it is SLeX that specifically binds sperm to an egg.According to the World Health Organisation, infertility affects about 15 percent of reproductive-aged couples around the world and almost one in every seven couples in Britain has problems conceiving a child for various reasons.