Comet Holmes in Outburst
Credit & Copyright: Babak Tafreshi and (inset) Alan Friedman
Explanation: Comet 17P/Holmes stunned comet watchers across planet Earth earlier this week. On October 24, it increased in brightness over half a million times in a matter of hours. The outburst transformed it from an obscure and faint comet quietly orbiting the Sun with a period of about 7 years to a naked-eye comet rivaling the brighter stars in the constellation Perseus. Recorded on that date, this view from Tehran, Iran highlights the comet's (enhanced and circled) dramatic new visibility in urban skies. The inset (left) is a telescopic image from a backyard in Buffalo, New York showing the comet's greatly expanded coma, but apparent lack of a tail. Holmes' outburst could be due to a sudden exposure of fresh cometary ice or even the breakup of the comet nucleus. The comet may well remain bright in the coming days.
福尔摩斯彗星爆发
说明:本周早些时候,彗星17P/Holmes让地球上的观彗者们着实惊叹了一把。10月24日,在数小时内它的亮度增加了50万倍之多。爆发前它只是一颗大约每7年静悄悄地绕太阳运行一周的昏暗彗星,而如今却成了一颗能与英仙座亮星媲美的肉眼可见彗星。这张照片就是在当天拍摄的,地点是伊朗首都德黑兰。图中突显了肉眼可见的彗星(图中被圈出并增强)出现在城市的天空中。插图(左侧)是在纽约州水牛城人家的后院里用望远镜拍摄的照片,其中显示了彗星非常膨胀的彗发,但看不到彗尾。Holmes彗星爆发的原因可能是彗冰的突然暴露,甚至可能是彗核分裂。在今后的几天里,这颗彗星还将保持明亮的状态。
(美的眼睛 翻译) |