... The Colorful Clouds of Rho Ophiuchi . ... Near the top, Rho Ophiuchi and nearby stars are immersed in blue reflection nebulae - dust clouds that shine primarily by reflected starlight . ... Characteristic of star forming regions, the telltale red emission from hydrogen gas also permeates the view along with dark, obscuring dust clouds seen in silhouette against the background stars and brighter nebulosities. ... Publications with keywords: emission nebula - dark nebula - reflection nebula . ...