charles 2009-3-27 11:10
冰島的火山和極光
Volcano and Aurora in Iceland
[img]http://i17.tinypic.com/2i1hv9u.jpg[/img]
影像提供: Sigurdur H. Stefnisson
[color=navy]Explanation: [/color]
[color=dimgray]Sometimes both heaven and Earth erupt. In Iceland in 1991, the volcano Hekla erupted at the same time that auroras were visible overhead. Hekla, one of the most famous volcanoes in the world, has erupted at least 20 times over the past millennium, sometimes causing great destruction. The last eruption occurred only six years ago but caused only minor damage. The green auroral band occurred fortuitously about 100 kilometers above the erupting lava. Is Earth the Solar System's only planet with both auroras and volcanos? [/color]
[color=navy]說明:[/color]
[color=dimgray]有時候天與地會同時上演爆發的場面。場景是1991年的冰島。當極光 現身於頭頂上方的同時， Hekla火山爆發了。身為世界上最著名火山之一的 Hekla火山，在過去一千年來已噴發了至少20次，有時還釀成嚴重的災情。最近一次的爆發僅發生在2年多前，幸而只造成較小的損害。圖中綠色的極光帶非常偶然地發生在噴發出的熔岩上空約100公里處。一個有趣的問題: 地球是否是太陽系裡唯一同時擁有極光與火山的行星? [/color]
[size=2]資料來源: Scientific American
Department of Physics, NCKU[/size][color=white][size=1][/size][/color]