【提名项目】：1 【提名标题】：太阳系只有「八大行星」，冥王星被降级 【资料来源】： 一：http://tw.news.yahoo.com/article/url/d/a/060824/19/2jnf.html 二：http://www.msnbc.msn.com/id/15460884/site/newsweek/ 【资料内容】： 一：新闻标题：行星定义修正通过冥王星降级，九大行星不再[节录] （法新社布拉格二十四日电） 国际天文学联合会（ＩＡＵ）今天表决通过修正行星定义 ，冥王星遭到降级，失去七十年来公认为太阳系第九大行星、也是最外缘行星的地位，太 阳系从此成为八大行星。经过激烈辩论，联合会今天以举手表决方式通过决议：「八大行 星分别为水星、地球、金星、火星、木星、土星、天王星与海王星。」美国天文学家一九 三零年二月八日发现冥王星，当时他只有二十四岁。 二：新闻标题：Plotting Pluto's Comeback[节录] Nov. 6, 2006 issue - To Bob Millis, director of the Lowell Observatory in Flagstaff, Az., Pluto is still the ninth planet, no matter what the Inter- national Astronomical Union chooses to call it. It was Lowell's founder and namesake, Percival Lowell, who predicted mathematically the existence of a "Planet X" beyond Neptune, and it was at the observatory that it was found and named (for the Roman god of the underworld) in 1930.There have been other significant discoveries at Lowell over the years, but finding Pluto remains its signature public achievement. Which is why Millis thinks it was "premature" of the IAU to vote last summer to define "planet" in a way that excluded Pluto. Now, it turns out, Pluto may be headed for a comeback.It's not just Millis who feels Pluto got a raw deal. Other astronomers think the new definition is a mistake—not just on Pluto's account, but on behalf of all the rocky, icy or gaseous objects, already known or yet to be discovered, circling the Sun or distant stars. Although the IAU isn't scheduled to meet again until 2009, plans are being laid for an ad hoc conference of astronomers next year to come up with another new definition of "planet"—one that will almost certainly restore Pluto's status. The IAU definition, says Millis, seems to cast "a mantle of insignificance" over that whole region of space, "the hottest topic in planetary studies today." 【补充建议】： 从小到大，我们脑中最根深蒂固的天文知识竟然被推翻了！冥王星竟遭IAU降级，太阳 系自此从九大行星改为八大行星。大会认为行星应绕行恒星，本身拥有足够质量而自行产 生重力，可克服各种刚体的力，因此能维持流体静力平衡（近似球形），同时公转的轨道 空间并未与其它行星交会。而冥王星失去行星资格，是因为其椭圆形的公转轨道会跟海王 星交会。影响不仅及於天文学界，连教科书都要大幅度的修正，甚至对占星都产生影响。 -- █ ▍██████◤ █ ＳＷＥＤＥＮ ▍█████◤ █ SIMPLE, POWERFUL, COURAGEOUS ▍████◤ █ YOU HAVE THE SUPPORT OF EVERYONE! ▍███◤ ████████████████████████████████████ █ ▍█◤[email protected] --

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