NGC 6822: 巴纳德星系

NGC 6822: 巴纳德星系

NGC 6822: Barnard’s Galaxy
Image Credit & Copyright: Dietmar Hager, Eric Benson

Explanation: Grand spiral galaxies often seem to get all the glory, flaunting their young, bright, blue star clusters in beautiful, symmetric spiral arms. But small galaxies form stars too, like nearby NGC 6822, also known as Barnard’s Galaxy. Beyond the rich starfields in the constellation Sagittarius, NGC 6822 is a mere 1.5 million light-years away, a member of our Local Group of galaxies. A dwarf irregular galaxy similar to the Small Magellanic Cloud, NGC 6822 is about 7,000 light-years across. Brighter foreground stars in our Milky Way have a spiky appearance. Behind them, Barnard’s Galaxy is seen to be filled with young blue stars and mottled with the telltale pinkish hydrogen glow of star forming regions in this deep color composite image.

Tomorrow’s picture: Queequeg’s comet

NGC 6822: 巴纳德星系
影像提供与版权: Dietmar Hager, Eric Benson

说明: 拥有美丽对称螺旋臂、上头镶着明亮年轻蓝色星团的宏伟螺旋星系，看似独享所有的风采和注意。其实小星系也会形成恒星，例证之一为邻近的巴纳德星系（NGC 6822）。位在人马座方向富星场的后方，离我们约只有150万光年远的NGC 6822，是本星系群的成员之一。 NGC 6822的跨幅约有7,000光年，是个形似小麦哲伦星系的不规则矮星系。在这幅彩色深空组合影像里，带芒的较明亮天体，是近在银河系之内的前景恒星。而位于它们后方的巴纳德星系，其内看似满布着年轻的泛蓝恒星，并缀着散发氢粉红辉光的恒星形成区。

明日的图片: Queequeg’s comet