... Molecular Cloud Barnard 68 . ... What used to be considered a hole in the sky is now known to astronomers as a dark molecular cloud . Here, a high concentration of dust and molecular gas absorb practically all the visible light emitted from background stars. ... It is not known exactly how molecular clouds like Barnard 68 form, but it is known that these clouds are themselves likely places for new stars to form . ... Publications with keywords: Barnard 68 - molecular cloud - dust . ...