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  • 类别:百科文化
  • 作者:未知
  • 播音:未知
  • 更新时间:2019年05月22日
  • 状态:连载中

作品介绍

天文知识之行星恒星
       新的天文发现不断使“九大行星”的传统观念受到质疑,美排位图国天文学家错估了冥王星的质量,将冥王星列入了九大行星之内。后来,发现冥王星的质量低于月球,被排除九大行星之外。天文学家先后发现冥王星与太阳系其他行星的一些不同之处。冥王星所处的轨道在海王星之外,属于太阳?#20302;?#22260;的柯伊伯带,这个区域一?#31508;?#22826;阳系小行星和彗星诞生的地方。20世纪90年代以来,天文学家发现柯伊伯带有更多围绕太阳运行的大天体。比如,美国天文学?#20063;?#26391;发现的“2003UB313”,就是一个直径和质量都超过冥王星的天体。因此,?#21360;?#20061;大行星”改为“八大行星”就不难理解了。

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