参宿七的大视野影像

参宿七的大视野影像

2023年4月7日 Rigel Wide Image Credit: Rheinhold Wittich Explanation: Brilliant, blue, supergiant star Rigel marks the foot of Orion the Hunter in planet Earth’s night. Designated Beta Orionis, it’s at the center of this remarkably deep and wide field of view. Rigel’s blue color indicates that it is much hotter than its rival supergiant in Orion the yellowish Betelgeuse (Alpha Orionis), though both stars are massive enough to eventually end their days as core collapse supernovae. Some 860 light-years away, Rigel is hotter than the Sun too and extends to about 74 times the solar radius. That’s about the size of the orbit of Mercury. In the 10 degree wide frame toward the nebula rich constellation, the Orion Nebula is at the upper left. To the…

参宿七与女巫头星云

参宿七与女巫头星云

2022年1月24日 Rigel and the Witch Head Nebula Image Credit & Copyright: José Mtanous Explanation: By starlight this eerie visage shines in the dark, a crooked profile evoking its popular name, the Witch Head Nebula. In fact, this entrancing telescopic portrait gives the impression that the witch has fixed her gaze on Orion’s bright supergiant star Rigel. More formally known as IC 2118, the Witch Head Nebula spans about 50 light-years and is composed of interstellar dust grains reflecting Rigel’s starlight. The blue color of the Witch Head Nebula and of the dust surrounding Rigel is caused not only by Rigel’s intense blue starlight but because the dust grains scatter blue light more efficiently than red. The same physical process causes Earth’s daytime sky to appear…