Infrared dark cloud

An infrared dark cloud (IRDC) is a cold, dense region of a giant molecular cloud. They can be seen in silhouette against the bright diffuse mid-infrared emission from the galactic plane. An infrared dark cloud (IRDC) is a cold, dense region of a giant molecular cloud. They can be seen in silhouette against the bright diffuse mid-infrared emission from the galactic plane. Infrared dark clouds have only been recently discovered in 1996 using the ISO and therefore are in need of further research. Astronomers believe that they represent the earliest stage in the formation of high-mass stars and are therefore of great importance for understanding the star formation process as a whole.