造父四

2023年10月12日

Mu Cephei
Image Credit & Copyright: David Cruz

Explanation: Mu Cephei is a very large star. An M-class supergiant some 1500 times the size of the Sun, it is one of the largest stars visible to the unaided eye, and even one of the largest in the entire Galaxy. If it replaced the Sun in our fair Solar System, Mu Cephei would easily engulf Mars and Jupiter. Historically known as Herschel’s Garnet Star, Mu Cephei is extremely red. Approximately 2800 light-years distant, the supergiant is seen near the edge of reddish emission nebula IC 1396 toward the royal northern constellation Cepheus in this telescopic view. Much cooler and hence redder than the Sun, this supergiant’s light is further reddened by absorption and scattering due to intervening dust within the Milky Way. A well-studied variable star understood to be in a late phase of stellar evolution, Mu Cephei is a massive star too, destined to ultimately explode as a core-collapse supernova.

APOD editor to speak: in Houghton, Michigan on Thursday, October 12 at 6 pm

Tomorrow’s picture: pixels in space

造父四
影像提供与版权: David Cruz

说明: 造父四是一颗很庞大的恒星。它的分类为M型的超巨星，直径约莫是太阳的1,500倍，是肉眼可见的最大恒星之一，甚至是整个银河系最庞大的恒星之一。如果用它来取代太阳系的太阳，那么造父四可轻易吞没火星和木星。造父四的色泽极红，在历史上有赫歇尔的石榴石星之称。这颗超巨星的温度远比太阳低，本来就比太阳红，更由于银河系居间的尘埃之吸收和散射作用，因此它的星光受到进一步红化。在这片远眺北天仙王座方向的望远镜视野里，这颗距离我们约2800光年的超巨星，紧邻着泛红的发射星云IC 1396。这颗备受研究、咸信处于恒星演化末期的大质量变星，最终注定会以星核塌缩超新星的形式发生爆炸。 （Mu Cephei 造父四）

APOD编辑发言: 10月12日星期四下午6点在密歇根州霍顿

明日的图片: pixels in space