2019 July 31
IC 1795: The Fishhead Nebula
Image Credit & Copyright: Alan Pham
Explanation: To some, this nebula looks like the head of a fish. However, this colorful cosmic portrait really features glowing gas and obscuring dust clouds in IC 1795, a star forming region in the northern constellation Cassiopeia. The nebula’s colors were created by adopting the Hubble color palette for mapping narrow emission from oxygen, hydrogen, and sulfur atoms to blue, green and red colors, and further blending the data with images of the region recorded through broadband filters. Not far on the sky from the famous Double Star Cluster in Perseus, IC 1795 is itself located next to IC 1805, the Heart Nebula, as part of a complex of star forming regions that lie at the edge of a large molecular cloud. Located just over 6,000 light-years away, the larger star forming complex sprawls along the Perseus spiral arm of our Milky Way Galaxy. At that distance, this picture would span about 70 light-years across IC 1795.
影像来源与版权: Alan Pham
说明：对某些人来说，这个星云看起来像一个鱼头。然而，这幅彩色的宇宙影像实际上呈现了位于北天仙后座的恒星形成区IC 1795内的炽热气体和模糊尘埃云。该星云的颜色采用了哈勃调色板，将氧原子、氢原子和硫原子的窄波段辐射分别渲染成蓝色、绿色和红色，再将数据与通过宽带滤波器拍摄的区域影像进一步结合而形成的。在距离英仙座内著名的双星团不远的天空中，IC 1795本身紧挨着心脏星云IC 1805，它是位于巨大分子云边缘的恒星形成区复杂体的一部分。这个较庞大的恒星形成复杂体距离我们超过6000光年远，蜿蜒分布在我们银河系的英仙座旋臂上。以这个距离来计算，这幅影像的跨度约70光年。