LDN-1235, The Dark Shark

Often referred to as the Shark Nebula, LDN 1235 is a striking dark nebula located approximately 650 light-years away in the constellation Cepheus. It was cataloged by American astronomer Beverly Lynds in her 1962 Catalogue of Dark Nebulae, which she compiled using the red and blue plates from the Palomar Observatory Sky Survey. This "dark" nebula is essentially a dense, cold cloud of interstellar dust that is so thick it obscures nearly all visible light from the stars behind it. In terms of opacity, LDN 1235 is classified as an Opacity Class 5 or 6 (on a scale of 1–6), meaning it is among the most light-blocking regions in the sky. While it appears as a void in traditional broadband images, it is actually a site of high-latitude galactic cirrus, reflecting a faint, ghostly blue light from nearby stars—a phenomenon known as an Extended Red Emission (ERE).