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By Paul Sisco Washington, DC 24 May 2006 watch Melting Poles report NASA scientists, working with 10 years of satellite data, find a dramatic thinning of ice around the edges of Greenland, and Antarctica too. satellite view of earth Using satellite
2006年VOA标准英语（五月）
By Paul Sisco Washington, D.C. 24 November 2006 watch Polar Melting report 2007 is International Polar Year. It's an international effort to spur scientific research at the most forbidding places on Earth, primarily because many in science consider
2006年VOA标准英语（十一月)
Earth's magnetic field has reversed thousands of times since its formation 4.5 billion years ago. And scientists now believe that the next reversal is imminent. The race is on to predicting exactly when it will occur. In 2010, the European Space Agen
自然百科2011年
Glatsmire's model shows that the magnetic poles swap places spontaneously due to / complex processes within the core. We were used to the idea that a compass points somewhere near the North Pole and hence we can use it for navigation, but there are p
自然百科2011年
To complicate matters, after Picard's death the father-and-son team of Giovanni and Jacques Cassini repeated Picard's experiments over a larger area and came up with results that suggested that the Earth was fatter not at the equator but at the poles
万物简史
63 火星的神秘运动 DATE=6-27-01 TITLE=SCIENCE REPORT - The Motion of Mars BYLINE=Mario Ritter (Start at 59
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