Dark nebula

Type of interstellar cloud that obscures visible light The dark nebula LDN 1768 in front of background stars Star formation Object classes Interstellar medium Molecular cloud Bok globule Dark nebula Young stellar object Protostar Pre-main-sequence star T Tauri star Herbig Ae/Be star Herbig–Haro object Theoretical concepts Accretion Initial mass function Jeans instability Kelvin–Helmholtz mechanism Nebular hypothesis Planetary migration vte A dark nebula or absorption nebula is a type of interstellar cloud, particularly molecular clouds, that is so dense that it obscures the visible wavelengths of light from objects behind it, such as background stars and emission or reflection nebulae. The extinction of the light is caused by interstellar dust grains in the coldest, densest parts of molecular clouds. Clusters and large complexes of dark nebulae are associated with Giant Molecular Clouds. Isolated small dark nebulae are called Bok globules. Like other interstellar dust or material, the objects obscured are visible only using radio waves or infrared light, using techniques from radio and infrared astronomy Dark clouds appear so because of sub-micrometre-sized dust particles, coat