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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.

HOUSTON, July 25 (Xinhua) -- A shelter-in-place was ordered after a battery caught fire during a testing at NASA's Johnson Space Center Monday morning.A battery was being tested inside a containment system when it got overheated and caught fire at about 9 a.m. local time, ABC quoted the Houston Fire Department (HFD) sources as reporting.A shelter-in-place was issued for a few buildings because it's believed that one of the bi-products of the combustion could be dangerous, HFD said.The fire was put out before 11:30 a.m.A firefighter was injured when a hydrant cap blew off and struck him, according to ABC.

XICHANG, Sichuan, July 12 (Xinhua) -- China blasted off a new data relay satellite "Tianlian I-02" on Monday at the Xichang Satellite Launch Center in southwest Sichuan Province .The satellite was launched on a Long March-3C carrier rocket at 11:41 p.m. (Beijing Time), said sources with the center.Developed by the China Academy of Space Technology under the China Aerospace Science and Technology Corporation, the satellite is the country's second data relay satellite.China launched its first data relay satellite "Tianlian I-01" on April 25, 2008.The two satellites will form a network to offer data relay and measurement and control service for China's spacecrafts and planned space stations, according to the center.They will also be used to help perform the nation's first space docking, scheduled for the second half of 2011.China plans to launch Tiangong-1 and Shenzhou-8 spacecraft in the latter half of this year, and they will perform the nation's first space docking.Monday's launch is the 140th mission of China's Long March series of rockets.

SAN FRANCISCO, July 12 (Xinhua) -- U.S. videogame giant Electronic Arts Inc. (EA) on Tuesday said it has agreed to buy PopCap Games, a leading provider of casual games for digital platforms, in a deal to accelerate its digital transformation.EA said it will pay about 650 million U.S. dollars in cash and 100 million dollars in shares of EA common stock to acquire privately-held PopCap, the maker of blockbuster games including " Plants vs. Zombies," "Bejeweled" and "Zuma".In addition, PopCap's owners are entitled to receive as much as 550 million dollars in earn-outs if certain earnings targets are met through December 2013, according to EA, which is headquartered in Redwood City in the U.S. state of California.Logos of PopCap Games and Electronic Arts Inc."EA and PopCap are a compelling combination," John Riccitiello, EA's chief executive officer, said in a statement."PopCap's great studio talent and powerful IP add to EA's momentum and accelerate our drive towards a 1-billion-dollar digital business," he noted.PopCap is one of the largest providers of casual videogames for mobile phones, tablets, PCs and social network sites, with more than 150 million games installed and played worldwide on platforms such as Facebook, RenRen, Google, iPhone, iPad and Android.EA said the purchase of PopCap is expected to close in August this year, subject to customary closing conditions including regulatory approvals.

PARIS, Sept. 21 (Xinhua) -- European heavy-lift launcher Ariane 5 lifted off two communication satellites Wednesday from the Kourou launch centre in French Guiana, live broadcast of the launching process showed.The rocket, carrying the two communication satellites Arabsat 5C and SES-2, was launched at GMT 2138.This was the fifth heavy-lift mission of Ariane 5 in 2011. Arianespace had planned six Ariane 5 missions through 2011.The satellite Arabsat-5C was developed for the Arab Satellite Communications Organization (Arabsat) to provide satellite capacity in both C-band and Ka-band frequencies for a wide range of communications services.Jointly produced by Europe's EADS Astrium and Thales Alenia Space, it will be positioned at 20 degree East orbital location to cover the Middle East and Africa.Manufactured by Orbital Sciences Corporation of the United States, SES-2 will join the fleet of European satellite telecommunications operator SES, and is to be positioned at 87 degree West for coverage over North America and the Caribbean.Both Arabsat-5C and SES-2 have life-spans as long as 15 years.This Ariane 5 dual-passenger mission was postponed from Tuesday due to local strikes of French Guiana workers.Founded in 1980 as the world's first launch service and solutions company, Arianespace planned to achieve six Ariane 5 missions through 2011. Through 2010, heavy-lift workhorse Ariane 5 finished six missions, sending a dozen spacecraft into expected orbits.The next mission from Arianespace centre in Kourou was scheduled for Oct. 20 by medium-lift vehicle Soyuz. It will be Soyuz' first mission from French Guiana with a pair of satellites for Europe's Galileo satellite navigation system.

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