NGC7635 Bubble Nebula crop

NGC 7635, called the "Bubble Nebula" — is an emission nebula in the constellation Cassiopeia. The "Bubble" was formed by the stellar wind from a hot, massive Wolf–Rayet star SAO 20575 (BD+60 2522), which has an apparent magnitude of 8.7 and a mass of 10-40 solar masses. The nebula itself is part of a giant molecular cloud located at a distance of 7,100 — 11,000 light-years from the Sun.