Louissai 2011-11-15 23:48
CFHT望遠鏡拍攝到雷神的頭盔
Thor's Helmet from CFHT <br />
<br />
<img src="http://i5.tinypic.com/4hlb53n.jpg" border="0" onclick="zoom(this)" onload="attachimg(this, 'load')" alt="" /><br />
<br />
影像提供與版權: Jean-Charles Cuillandre (CFHT), Hawaiian Starlight, CFHT <br />
<br />
<img src="http://i14.tinypic.com/35ldp2t.jpg" border="0" onclick="zoom(this)" onload="attachimg(this, 'load')" alt="" /><br />
<br />
<font color="navy">Explanation: </font><br />
<font color="dimgray">NGC 2359 is a striking emission nebula with an impressive popular name - Thor's Helmet Sure, its suggestive winged appearance might lead some to refer to it as the "duck nebula", but if you were a nebula which name would you choose? By any name NGC 2359 is a bubble-like nebula some 30 light-years across, blown by energetic winds from an extremely hot star seen near the center and classified as a Wolf-Rayet star. Wolf-Rayet stars are rare massive blue giants which develop stellar winds with speeds of millions of kilometers per hour. Interactions with a nearby large molecular cloud are thought to have contributed to this nebula's more complex shape and curved bow-shock structures. NGC 2359 is about 15,000 light-years distant toward the constellation Canis Major. </font><br />
<br />
<font color="navy">說明:</font><br />
<font color="dimgray">NGC 2359 是一個醒目的發射星雲,它有另外一個響亮的名字 -- 雷神的頭盔。當然,有人會因為它有翼狀的側邊而認為它應該稱為"鴨子"星雲,不過如果你是個星雲,你會選擇哪個名字?不管NGC 2359 要用哪個名字,它是一個大小約 30 光年的泡泡狀星雲,是由中央有顆極高溫星球強烈的恆星風所吹出來的,這類星球是屬於沃夫-瑞葉型星。 沃夫-瑞葉型星是種罕見的大質量藍巨星,能吹出時速高達數百萬公里的恆星風。在恆星風和鄰近的巨大分子雲的交互作用之下,便產生了這個星雲複雜的外型和彎曲的弓狀震波結構。NGC 2359位於大犬座內,距離地球約15,000光年遠。 </font><br />
<br />
<font size="2">資料來源: Scientific American<br />
Department of Physics, NCKU</font><font color="white"><font size="1"><br />
</font></font>