NGC 3521:气泡里的星系



NGC 3521: Galaxy in a Bubble
Image Credit & Copyright:
Mark Hanson and Mike Selby

Explanation: Gorgeous spiral galaxy NGC 3521 is a mere 35 million light-years away, toward the northern springtime constellation Leo. Relatively bright in planet Earth’s sky, NGC 3521 is easily visible in small telescopes but often overlooked by amateur imagers in favor of other Leo spiral galaxies, like M66 and M65. It’s hard to overlook in this colorful cosmic portrait though. Spanning some 50,000 light-years the galaxy sports characteristic patchy, irregular spiral arms laced with dust, pink star forming regions, and clusters of young, blue stars. This deep image also finds NGC 3521 embedded in fainter, gigantic, bubble-like shells. The shells are likely tidal debris, streams of stars torn from satellite galaxies that have undergone mergers with NGC 3521 in the distant past.

Tomorrow’s picture: southern tadpoles

NGC 3521:气泡里的星系
Mark Hanson and Mike Selby

说明: 在狮子座方向的壮丽螺旋星系NGC 3521,离我们只有3千5百万光年远。在北半球春天狮子座方向、距离只有3千5百万光年远的壮丽NGC 3521,是地球天空中相对明亮用小望远镜即轻易可见的天体,但因狮子座内有其他更吸睛诸如M66和M65等螺旋星系,而常被业余天文摄影者所忽视。不过,在上面这幅彩色的宇宙天体影像中,要忽视它可不容易。这个宽约50,000光年的星系,拥有特有断断续续的不规则螺旋臂,上面散布着尘埃、粉红色的恒星形成区、和成团的年轻蓝色恒星。而在这张深空影像里,更可发现星系NGC 3521是位在昏暗庞大的气泡状结构之内。这些壳层结构可能是潮汐尾碎片,是从很久以前和NGC 3521合并的伴星系剥离出来的恒星流。

明日的图片: southern tadpoles