1. A cluster of stars within an intricate cloud of gas and dust
   - gaseous nebula

Type of: nebula

Encyclopedia: Diffuse nebula

• hydrogen ion concentration
• hydrogen peroxide
• hydrogen sulfide
• hydrogen sulphide
• hydrogen-bomb
• hydrogenate
• hydrogenation
• hydrogenise
• hydrogenize
• hydrogenous
• hydrographer
• hydrographic
• hydrographical
• hydrography
• hydroid
• hydroiodic acid
• hydrokinetic
• hydrokinetics
• hydrolise
• hydrolith
• hydrolize
• hydrological
• hydrologist
• hydrology
• hydrolysable