IC 2118: 女巫头星云

IC 2118: 女巫头星云

2023年10月4日 IC 2118: The Witch Head Nebula Image Credit & Copyright: Abdullah Alharbi Explanation: Does this nebula look like the head of a witch? The nebula is known popularly as the Witch Head Nebula because, it is said, the nebula’s shape resembles a Halloween-style caricature of a witch’s head. Exactly how, though, can be a topic of imaginative speculation. What is clear is that IC 2118 is about 50 light-years across and made of gas and dust that points to — because it has been partly eroded by — the nearby star Rigel. One of the brighter stars in the constellation Orion, Rigel lies below the bottom of the featured image. The blue color of the Witch Head Nebula and is caused not only by…

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…