The surface of Mars is etched with ancient river valleys and lake basins. Which makes researchers think that liquid water once flowed on the Red Planet. But how? Today, Mars is too cold for much, if any, liquid water to exist. And 3.8 billion years a

发表于:2018-12-24 / 阅读(58) / 评论(0) 分类 2017年Scientific American(一)月

By David McAlary Washington 10 March 2006 Mars Reconnaissance Orbiter Another U.S. spacecraft has begun orbiting Mars to study the red planet in unprecedented detail. The Mars Reconnaissance Orbiter w

发表于:2019-01-07 / 阅读(119) / 评论(0) 分类 2006年VOA标准英语(三月)

By David McAlary Washington 21 November 2006 The U.S. space agency NASA says its oldest satellite orbiting Mars has probably ended its career. NASA engineers lost contact with it about three weeks ago and are losing hope of ever hearing from it agai

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By Jessica Berman Washington 29 May 2008 As the newly deployed Phoenix spacecraft begins its mission in search of life near Mars' northern pole, scientists say an analysis of Martian deposits suggest there was once water on the planet, but it was too

发表于:2019-01-13 / 阅读(66) / 评论(0) 分类 VOA标准英语2008年(五月)

NASA Mars Rover Will Face Harrowing Descent, Landing Curiosity is the centerpiece of the $2.5 billion Mars Science Laboratory spacecraft, launched in November aboard an Atlas V rocket. It's traveled some 560 million kilometers toward its destination,

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Ten Years of Roving Around Mars 十年的火星游荡 WASHINGTON The U.S. space agency, NASA, is celebrating the 10th anniversary of its Mars Exploration Rover Mission (MER), which began with the arrival of its robotic vehicles Spirit and Opportunity

发表于:2019-01-14 / 阅读(46) / 评论(0) 分类 VOA标准英语2014年(一月)

DAVID GREENE, HOST: This seems big. Scientists say for the first time they have clear evidence that the chemical building blocks of life exist on Mars. So is this the moment we can say there is life on the red planet? Well, NPR's Joe Palca says not y

发表于:2019-01-17 / 阅读(42) / 评论(0) 分类 2018年NPR美国国家公共电台6月

By Paul Sisco Washington, DC 02 August 2006 watch Viking report An illustration of a Viking landing on the red planet Thirty years after the first successful landing of a robotic probe on Mars by NASA's Viking spacecraft, the search for life on the

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