NGC 7814: 有超新星的小宽边帽星系

2021年7月22日

NGC 7814: Little Sombrero with Supernova
Image Credit & Copyright: CHART32 Team,

Explanation: Point your telescope toward the high flying constellation Pegasus and you can find this expanse of Milky Way stars and distant galaxies. NGC 7814 is centered in the pretty field of view that would almost be covered by a full moon. NGC 7814 is sometimes called the Little Sombrero for its resemblance to the brighter more famous M104, the Sombrero Galaxy. Both Sombrero and Little Sombrero are spiral galaxies seen edge-on, and both have extensive halos and central bulges cut by a thin disk with thinner dust lanes in silhouette. In fact, NGC 7814 is some 40 million light-years away and an estimated 60,000 light-years across. That actually makes the Little Sombrero about the same physical size as its better known namesake, appearing smaller and fainter only because it is farther away. In this telescopic view from July 17, NGC 7814 is hosting a newly discovered supernova, dominant immediately to the left of the galaxy’s core. Cataloged as SN 2021rhu, the stellar explosion has been identified as a Type Ia supernova, useful toward calibrating the distance scale of the universe.

Tomorrow’s picture: cosmic zoo

NGC 7814: 有超新星的小宽边帽星系
影像提供与版权: CHART32 Team,

说明: 把你的望远镜指向北天的飞马座，就能见到这大片的银河恒星和遥远星系。这片以星系NGC 7814为中心的美丽星野，跨幅将近有1个满月。NGC 7814因其形似较亮而且也较著名的宽边帽星系M104，故也称为小宽边帽星系。宽边帽星系和小宽边帽星系都是侧向的螺旋星系，两者都拥有被星系盘的细窄尘埃带所分割之星系晕和庞大星系核。NGC 7814的距离约为4千万光年远，其大小则在6万光年左右。小宽边帽星系之大小，其实和较著名的同名星系相当，它之所以较小较暗，只缘离我们较远。在这幅摄于今年7月17日的望远镜影像里，NGC 7814是位在星系核左侧的新发现超新星之寄主星系。这例编录号为SN 2021rhu的恒星爆炸事件，分类为可用来校正宇宙 距离尺标的Ia型超新星。

明日的图片: cosmic zoo