单词：
单词： 相关文章
Four times a year, Ghez focuses the telescope on the stars of the very heart of our Milky Way. She is looking for the telltale high speeds that reveal the presence of a black hole. The center of the M
超大质量黑洞
In every galaxy scientists looked at, they found evidence for a supermassive black hole. NGC 3115 NGC 3377 NGC 3379 In M31 and M32 In total there is probably 20-30 or so black holes that have been fou
超大质量黑洞
By measuring how fast these stars were moving, he could prove if there really was a black hole at the center of an active galaxy. I picked a galaxy nearby which is called NGC 1068, an active galaxy, w
超大质量黑洞
Egyptian archaeologists have discovered the bottom part of an unknown pyramid in the Sakkara area about 18 miles south of Cairo. NationalGeographic explorer-in-residence Dr. Zahi Hawass, the Secretary General of the Egyptian Supreme Council for Anti
国家地理2008年
Tim called Howard. Tim needed help. He needed help with his golf swing. He had a bad golf swing. He was a bad golfer. Howard had a good golf swing. He was a good golfer. Will you help me improve my golf swing? Tim asked. Yes, Ill help you improve you
简单慢速英语阅读
U.S. Defense Secretary Robert Gates said Thursday's vote by the Kyrgyz parliament to terminate the U.S. lease on a key air base used for supplying the Afghanistan war is not the last word on the subject, and the United States will continue to try to
VOA标准英语2009年(二月)