Sh 2-308

Sh 2-308, also known as the Dolphin Nebula, is a faint emission nebula located in the constellation Canis Major, approximately 4,500 to 5,000 light-years from Earth. It is a bubble-shaped structure formed by the powerful stellar wind of a hot Wolf–Rayet star (WR 6), which sweeps up surrounding material to create an expanding shell of ionized gas. The nebula spans about 60 light-years in diameter and emits predominantly in the Hα and [OIII] wavelengths. Sh 2-308 offers valuable insights into the late evolutionary stages of massive stars and their interaction with the interstellar medium.