【提名項目】：1 【提名標題】：太陽系只有「八大行星」，冥王星被降級 【資料來源】： 一：http://tw.news.yahoo.com/article/url/d/a/060824/19/2jnf.html 二：http://www.msnbc.msn.com/id/15460884/site/newsweek/ 【資料內容】： 一：新聞標題：行星定義修正通過冥王星降級，九大行星不再[節錄] （法新社布拉格二十四日電） 國際天文學聯合會（ＩＡＵ）今天表決通過修正行星定義 ，冥王星遭到降級，失去七十年來公認為太陽系第九大行星、也是最外緣行星的地位，太 陽系從此成為八大行星。經過激烈辯論，聯合會今天以舉手表決方式通過決議：「八大行 星分別為水星、地球、金星、火星、木星、土星、天王星與海王星。」美國天文學家一九 三零年二月八日發現冥王星，當時他只有二十四歲。 二：新聞標題：Plotting Pluto's Comeback[節錄] 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." 【補充建議】： 從小到大，我們腦中最根深蒂固的天文知識竟然被推翻了！冥王星竟遭IAU降級，太陽 系自此從九大行星改為八大行星。大會認為行星應繞行恆星，本身擁有足夠質量而自行產 生重力，可克服各種剛體的力，因此能維持流體靜力平衡（近似球形），同時公轉的軌道 空間並未與其它行星交會。而冥王星失去行星資格，是因為其橢圓形的公轉軌道會跟海王 星交會。影響不僅及於天文學界，連教科書都要大幅度的修正，甚至對占星都產生影響。 -- █ ▍██████◤ █ ＳＷＥＤＥＮ ▍█████◤ █ SIMPLE, POWERFUL, COURAGEOUS ▍████◤ █ YOU HAVE THE SUPPORT OF EVERYONE! ▍███◤ ████████████████████████████████████ █ ▍█◤[email protected] --

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