引人注意的球状星团Omega其中心拥有2000000颗闪亮的恒星。在其光滑的边缘处也包含了10000000颗恒星，并且其中含有大约200个围绕银河系运动的体积庞大，质量巨大的球状星团。Omega星团距离地球17000光年。
天文学家Eva Noyola和Karl Gebhardt共同报道在Omega中心极有可能存在一个中级质量的黑洞。这个结论主要是根据智利双子天文台分光镜的测量结果得出，同时测量结果也指出恒星围绕中心的运动速度远比我们预计的要快。
在对于这些快速移动恒星的解释中—有一种非常支持他们的研究的结果—就是存在于Omega星团中心的中级质量黑洞大约相当于40000个太阳系质量。在这个强大引力的领域，加速了核心附近恒星的移动速度。
天文学家已经推测了好几年，一些质量中等或者体积中等的球状星团可能隐藏在中心，黑洞质量大约10倍于几千个太阳质量。中等大小的黑洞比超大黑洞的质量要小很多，超大黑洞的质量可以达到数十亿个太阳系质量，兵存在于更大的星系中。
这张照片是通过哈勃的高级巡天照相仪在关键区域的拍摄所得到：帮助精确定位星团的中心，更好的测量星团中心星光的总量。
使用位于Paranal和智利的欧洲南方天文台巨大的望远镜，Noyola和Gebhardt准备下步的观测，以证实中级质量黑洞的存在。
The core of the spectacular globular cluster Omega Centauri glitters with the combined light of 2 million stars. The entire cluster contains 10 million stars, and is among the biggest and most massive of some 200 globular clusters orbiting the Milky Way Galaxy. Omega Centauri lies 17,000 light-years from Earth.
Astronomers Eva Noyola, of the Max-Planck Institute of Extraterrestrial Physics in Garching, Germany, and Karl Gebhardt of the University of Texas at Austin, have reported on the possible detection of an intermediate-mass black hole in the core of Omega Centauri.
The result is primarily based on spectroscopic measurements obtained with the Gemini South observatory in Chile which suggest the stars are moving around the central core of the cluster at higher than expected velocities.
Among the possible explanations for these speedy stars — and the one favored by their study — is that an intermediate-mass black hole of approximately 40,000 solar masses resides at the center of Omega Centauri. Its powerful gravitational field speeds up the motions of stars near the core.
Astronomers have speculated for years that some globular clusters may harbor in their centers medium-size, or intermediate-mass, black holes with masses of some tens of thousands of suns. Medium-size black holes are much less massive than the supermassive black holes, which are up to billions of solar masses and reside in the centers of large galaxies.
Hubble images taken with the Advanced Camera for Surveys were used in key areas in support of this study: to help pinpoint the center of the cluster, as well as to measure the amount of starlight at the cluster center.
Using the European Southern Observatory's Very Large Telescope in Paranal, Chile, Noyola and Gebhardt are planning to obtain follow-up observations to help confirm the existence of an intermediate-mass black hole.
自翻
url:http://hubblesite.org/newscenter ... es/2008/14/image/a/
大图
红外大图（2400*3000）
[ 本帖最后由 江涛 于 2008-4-13 16:02 编辑 ] |
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置顶卡
变色卡
千斤顶
显身卡
太壮观了.
原来放大了是这样的。。。
