[分享] 哈勃望远镜观测到邻近星系多代恒星诞生[酷图]

　最近，哈勃太空望远镜对银河系的近邻大麦哲伦星系的观测发现，这里目前正在孕育着着一批新的星体。据哈勃望远镜传回来的资料显示，正在孕育和生成的新星体主要集中在大麦哲伦星系中名为N11B，和N11两个区域。

　　从哈勃所捕捉到的彩虹织锦般的全景图来看，这里正在生成一些气体、尘埃云以及年轻、炽热的恒星。

　　科学家称，新星的生成是以年老的巨大恒星的衰变为契机的。从目前的状况看，一些新的星体已经分布在年老巨大恒星的周围了。在新星诞生的区域中，常常能够观测到巨大的炽热恒星，这些恒星周围的气体和宇宙尘埃相对较少，它们的面目相对清晰一些，因为来自它本身的恒星风和放射射线将很大一部分气体吹散。当这些气体和它们周围的物质相遇，就开始聚集和结合在一起，并且越积越多，在自身重力的作用下，开始形成新的星体。这种情形在更遥远的星系中也可以观测到，当然这还得借助于哈勃太空望远镜。

　　观测还发现了一些颜色暗淡的云球和形状不规则的星际尘埃，它们和闪闪发亮的星际气体形成鲜明的对比。它们色彩暗淡的原因是由于附近的热恒星的“照明”和蒸发了它们的一部分气体。

　　科学家们还在大麦哲伦星系的N11区域发现了三代恒星：“祖母星”，她们孕育了大批的巨大的蓝白“母亲星”，而在暗云球中还发现了“星宝宝”，它们则是刚刚诞生的。(梦飞/编译）

 
　　来源： 新浪科技  2004-07-07 14:39


Hubble Studies Generations of Star Formation in Neighboring Galaxy

 
STScI-PRC2004-22  


NASA's Hubble Space Telescope captures this iridescent tapestry of star birth in a neighboring galaxy in this panoramic view of glowing gas, dark dust clouds, and young, hot stars. The star-forming region, catalogued as N11B, lies in the Large Magellanic Cloud (LMC), located only 160,000 light-years from Earth. With its high resolution, the Hubble Space Telescope is able to view details of star formation in the LMC as easily as ground-based telescopes are able to observe stellar formation within our own Milky Way galaxy. This new Hubble image zooms in on N11B, which is a small subsection within an area of star formation cataloged as N11. N11 is the second largest star-forming region in the LMC. Within the LMC, N11 is surpassed in size and activity only by the immense Tarantula nebula (also known as 30 Doradus.)

The image illustrates a perfect case of sequential star formation in a nearby galaxy where new star birth is being triggered by previous-generation massive stars. A collection of blue- and white-colored stars near the left of the image are among the most massive stars known anywhere in the universe. The region around the cluster of hot stars in the image is relatively clear of gas, because the stellar winds and radiation from the stars have pushed the gas away. When this gas collides with and compresses surrounding dense clouds, the clouds can collapse under their own gravity and start to form new stars. The cluster of new stars in N11B may have been formed this way, as it is located on the rim of the large, central interstellar bubble of the N11 complex. The stars in N11B are now beginning to clear away their natal cloud, and are carving new bubbles in turn. Yet another new generation of stars is now being born in N11B, inside the dark dust clouds in the center and right-hand side of the Hubble image. This chain of consecutive star birth episodes has been seen in more distant galaxies, but it is shown very clearly in this new Hubble image.

Farther to the right of the image, along the top edge, are several smaller dark clouds of interstellar dust with odd and intriguing shapes. They are seen silhouetted against the glowing interstellar gas. Several of these dark clouds are bright-rimmed because they are illuminated and are being evaporated by radiation from neighboring hot stars.

This image was taken with Hubble's Wide Field Planetary Camera 2 using filters that isolate light emitted by hydrogen and oxygen gas. The science team, led by astronomers You-Hua Chu (University of Illinois) and Yäel Nazé (Universite de Liège, Belgium) are comparing these images of N11B, taken in 1999, with similar regions elsewhere in the LMC. This color composite image was co-produced and is being co-released by the Hubble Heritage Team (STScI) and the Hubble European Space Agency Information Center (HEIC).

Image Credit: NASA, ESA, and The Hubble Heritage Team (AURA/STScI)

Acknowledgment: Y.-H. Chu (U. Illinois, Urbana-Champaign) and Y. Nazé (U. Liège, Belgium)

Image Type: Astronomical
STScI-PRC2004-22

:eek: http://imgsrc.hubblesite.org/hu/db/2004/22/images/a/formats/print.jpg