矮星系NGC 1569内的星爆现象

来源：成大APOD

矮星系NGC 1569内的星爆现象
影像提供: NASA, ESA, Hubble Heritage (STScI/AURA); 致谢: A. Aloisi (STScI/ESA) et al.

说明: 宏伟的螺旋星系通常是天之娇子，得意扬扬地展示它们对称漩涡臂上的年轻明亮星团。 不过，小型的不规则星系也会有恒星诞生活动呢。 譬如，上图中的矮星系NGC 1569就正在历经一次大量的恒星形成活动，而且启始的时间可以倒推到二千五百万年前。星爆活动所产生的混乱环境，主要是由许多的超新星爆炸所造成的。这些宇宙级爆炸不但会喷攦物质，也会触发新一波的恒星诞生活动。位在我们螺旋状银河系的两个大型星团，恰好出现在这张哈伯太空望远镜影像的中左方，它们可以视为是球状星团的年轻范例。这张影像涵盖了NGC 1569内部8000光年的区域。距离我们只有一千一百万光年的NGC 1569，是个离我们相当近的星爆星系，因此成为天文学家探索快速演化星系内恒星族群的绝佳目标。 NGC 1569位在具有长长脖子的鹿豹座(Camelopardalis)内。

非常漂亮啊,值得学习,顶一下

拍摄的挺漂亮的。

好图！！

好悲烈啊，不过图片挺漂亮的！

Two massive star clusters - youthful counterparts to globular star clusters in our own spiral Milky Way galaxy - are seen left of center in the gorgeous Hubble Space Telescope image.
“位在我们螺旋状银河系的两个大型星团，恰好出现在这张哈伯太空望远镜影像的中左方，它们可以视为是球状星团的年轻范例。”

好像有点偏，怎么会突然离开主题矮星系NGC 1569来谈银河系的两个大型星团呢？请看下文：
ABOUT THIS IMAGE:
This image taken by NASA's Hubble Space Telescope showcases the brilliant core of one of the most active galaxies in our local neighborhood. The entire core is 5,000 light-years wide.

The galaxy, called NGC 1569, sparkles with the light from millions of newly formed young stars. NGC 1569 is pumping out stars at a rate that is 100 times faster than the rate observed in our Milky Way Galaxy. This frenzied pace has been almost continuous for the past 100 million years.

The core's centerpiece is a grouping of three giant star clusters, each containing more than a million stars. (Two of the clusters are so close they appear as one grouping.) The clusters reside in a large, central cavity. The gas in the cavity has been blown out by the multitude of massive, young stars that already exploded as supernovae. These explosions also triggered a violent flow of gas and particles that is sculpting giant gaseous structures. The sculpted structure at lower right is about 3,700 light-years long.

Huge bubbles of gas, such as the two at left, appear like floating islands. The largest bubble is about 378 light-years wide and the smallest 119 light-years wide. They are being illuminated by the radiation from the bright, young stars within them. Some of those stars are peeking through their gaseous cocoons.

The biggest and brightest objects surrounding the core are stars scattered throughout our Milky Way Galaxy. In contrast, the thousands of tiny white dots in the image are stars in the halo of NGC 1569. The galaxy is 11 million light-years from Earth.

A new analysis of NGC 1569 shows that it is one and a half times farther from Earth than astronomers previously thought. The extra distance places the galaxy in the middle of a group of about 10 galaxies centered on the spiral galaxy IC 342. Gravitational interactions among the group's galaxies may be compressing gas in NGC 1569 and igniting the star-birthing frenzy.

Hubble's Wide Field Planetary Camera 2 and Advanced Camera for Surveys made the observations of NGC 1569 in September 1999, November 2006, and January 2007.

来源：hubblesite.org。

（来源：Wikipedia, the free encyclopedia）
NGC 1569 contains two prominent super star clusters with different histories. Both clusters have experienced episodic star formation. Super star cluster A, located in the northwest of the galaxy, contains young stars (including Wolf-Rayet stars) that formed less than 5 million years ago as well as older red stars. Super star cluster B, located near the center of the galaxy, contains an older stellar population of red giants and red supergiants. Both of these star clusters are thought to have masses equivalent to the masses of the globular clusters in the Milky Way.

现在完全可以知道这两个大型星团根本就不在我们螺旋状银河系，更不是什么球状星团的年轻范例！

再看一下日语版的相关翻译：
二つの巨大な星団がこの豪華なハッブル宇宙望遠鏡による画像の中央左側に見えています。それらは、私達のいる渦状の天の川銀河にある球状星団(3)(globular star clusters)とよく似た若い星団です。