2025年7月31日
Supernova 2025rbs in NGC 7331
Image Credit: Ben Godson (University of Warwick)
Explanation: A long time ago in a galaxy 50 million light-years away, a star exploded. Light from that supernova was first detected by telescopes on planet Earth on July 14th though, and the extragalactic transient is now known to astronomers as supernova 2025rbs. Presently the brightest supernova in planet Earth’s sky, 2025rbs is a Type Ia supernova, likely caused by the thermonuclear detonation of a white dwarf star that accreted material from a companion in a binary star system. Type Ia supernovae are used as standard candles to establish the distance scale of the universe. The host galaxy of 2025rbs is NGC 7331. Itself a bright spiral galaxy in the northern constellation Pegasus, NGC 7331 is often touted as an analog to our own Milky Way.
Tomorrow’s picture: pixels in space
星系NGC 7331里的超新星2025rbs
影像提供: Ben Godson (University of Warwick)
说明: 很久很久以前，在离地球5000万光年远的星系里，一颗恒星发生爆炸。不过直到今年的7月14日，地球上的望远镜才侦测到来自这例超新星的光，天文学家并将这例河外瞬变事件命名为超新星2025rbs。目前是地球天空最明亮超新星的2025rbs，其分类为Ia型超新星，因为它可能是双星系统中的白矮星，吸积伴星的物质后所产生的热核爆炸。而Ia型超新星则可作为标准烛光，用以测定宇宙的距离。位于北天飞马座方向、作为2025rbs寄主星系的NGC 7331，本身是一个明亮的螺旋星系，其外观咸认和我们的银河系非常类似。
明日的图片: pixels in space
