| Rho Ophiuchi cloud (r Oph cloud) |
| A large nebulous region near the star Rho Ophiuchi (r Oph). It is a mixture of reflection nebulae, emission nebulae, dark absorption nebulae and molecular clouds, and is relatively close, at a distance of about 700 light years. Infrared observations reveal the presence of a cluster of at least 40 stars within the dark cloud. This is a region of very active star formation and contains many T Tauri stars and Herbig-Haro objects. |