半人马座 A(不是半人马座 α)距离地球仅1100万光年,是距地球最近的活跃星系。 这个特殊的椭圆星系也被称为NGC 5128,它的直径超过60,000光年。 这个锐利的哈勃太空望远镜特写镜头具有一个约8500光年的视场,其中包括半人马座 A的星系中心(左上方)。 半人马座 A显然是两个原本正常的星系碰撞的结果,导致了混乱的恒星形成区,巨大的星团和浓厚的尘埃带紧密地纠缠在这一区域。 在半人马座 A中心附近,被撕碎的恒星以及星际物质正被一个质量为太阳十亿倍的中央黑洞持续稳定地吞噬。 与其他活跃星系一样,从半人马座 A辐射来的无线电波,X射线和伽马射线能量由此产生。
A mere 11 million light-years away, Centaurus A is the closest active galaxy to planet Earth. Also known as NGC 5128, the peculiar elliptical galaxy is over 60,000 light-years across. A region spanning about 8,500 light-years, including the galaxy's center (upper left), is framed in this sharp Hubble Space telescope close-up. Centaurus A is apparently the result of a collision of two otherwise normal galaxies resulting in a violent jumble of star forming regions, massive star clusters, and imposing dark dust lanes. Near the galaxy's center, left over cosmic debris is steadily being consumed by a central black hole with a billion times the mass of the Sun. As in other active galaxies, that process likely generates the radio, X-ray, and gamma-ray energy radiated by Centaurus A.
版权:NASA, ESA,Hubble Heritage (STScI/ AURA)-ESA/Hubble Collaboration
撰文:Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
每日一图APOD from NASA
2020.02.22 |