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European space probe sent back the first detailed pictures of the frozen surface of Saturn's moon Titan
DARMSTADT, Germany- A European space probe Friday sent back the first detailed pictures of the frozen surface of Saturn's moon Titan, showing stunning black and white images of what appeared to be hilly terrain riddled with channels carved by some sort of liquid. One of the pictures, taken about 15 kilometres above the surface as the Huygens spacecraft descended by parachute to a safe landing following a seven-year voyage from Earth, showed a large dark mass that appeared to be a lake. Another appeared to show large frozen chunks scattered across the landscape. Titan is the first moon other than the Earth's to be explored. Scientists believe its atmosphere is similar to that of the young Earth, and studying it could provide clues to how life arose here. "I think all of us continue to be amazed as we watch our solar system unveil," NASA science administrator Alphonso Diaz said as the images were displayed on screens at mission control in Darmstadt, Germany. "It challenges all our preconceptions that all these planets are static places," Diaz said. "Seeing a planet emerge that has dynamics and complexity to it is just amazing." The wok-shaped Huygens probe was spun off from the Cassini mother ship on Dec. 24 before its descent to the surface of Titan. The mission is a joint effort of the European Space Agency, NASA and the Italian space agency. Scientists say they had received more than three hours of data from Huygens' descent, and more than 10 minutes of data from the surface itself. "I'm shocked. It's remarkable," said Carolyn Porco of the Cassini Imaging Centre. "There are river channels. There are channels cut by something . . . a fluid of some sort is my best guess. "This mission has been like a fantasy come true," she told CNN. "It's a great moment not only for science but for humankind." Applause erupted at mission control in Darmstadt in western Germany at news of the data transmission from the probe. "The scientific data we are collecting now shall unveil the secrets of this new world," said Jean-Jacques Dordain, ESA's general director. "This is a fantastic success for Europe." The heart of the mission was the probe's 2½-hour parachute descent, taking pictures and sampling the atmosphere before landing on Titan, where temperatures are estimated at 180 degrees below zero Celsius. Early signals confirmed it had powered up for entry and deployed the parachute, and officials were confident it had made a safe landing because Huygens was designed to go on transmitting from the surface for at least three minutes before its batteries died - a total transmission of less than three hours. But the signal had kept coming for more than five hours. Mission officials - who have waited since 1997 for Huygens to reach its destination - had tears in their eyes as the first signal was picked up, indicating that the probe was transmitting to the Cassini. Named after Titan's discoverer, the 17th-century Dutch astronomer Christiaan Huygens, the probe carries instruments to explore Titan's atmosphere and find out whether it has the cold seas of liquid methane and ethane that have been theorized by scientists.
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Timers inside the 320-kilogram probe awakened it just before it entered Titan's atmosphere. Huygens is shaped like a wok and covered with a heat shield to survive the intense heat of entry. The probe was designed to shed its heat shield during descent and use a special camera and instruments to collect information on wind speeds and the makeup of Titan's atmosphere for transmission back to Cassini and relay to ESA controllers in Darmstadt and NASA's Deep Space Network in California. Titan is the only moon in the solar system known to have a significant atmosphere. Rich in nitrogen and containing about six per cent methane, its atmosphere is believed to be 1½ times thicker than Earth's. Diaz said Titan may offer hints about the conditions under which life first arose on Earth. "Titan is a time machine," Diaz said. "It will provide us the opportunity to look at conditions that may well have existed on Earth in the beginning. It may have preserved in a deep freeze many chemical compounds that set the stage for life on Earth." Part of a $3.3-billion US international mission to study the Saturn system, Huygens is also equipped with instruments to study Titan's surface upon landing. The Cassini-Huygens mission was launched on Oct. 15, 1997, from Cape Canaveral, Fla., to study Saturn, its spectacular rings and many moons.-Melisa Eddy. Band of rogue guards at the Abu Ghraib prison
FORT HOOD, Texas- U.S. army Spc. Charles Graner, reputed ringleader of a band of rogue guards at the Abu Ghraib prison, was convicted Friday of abusing Iraqi detainees in a case that sparked international outrage when photographs were released that showed reservists gleefully abusing prisoners. Graner, the first soldier to be tried on charges arising from the scandal, was convicted of all five charges and faces up to 15 years behind bars. Graner stood at attention and looked straight ahead without expression as each verdict was read. His parents, Charles and Irma Graner, held hands tightly as they listened.
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