NGC 7635, also known as the Bubble Nebula, Sharpless 162, or Caldwell 11, is a H II region emission nebula in the constellation Cassiopeia. It lies close to the direction of the open cluster Messier 52. The "bubble" is created by the stellar wind from a massive hot, 8.7 magnitude young central star, SAO 20575.

Radius: 3.5 light years

Distance to Earth: 11,090 light years

Coordinates: RA 23h 20m 48s | Dec +61° 12′ 6″

Apparent magnitude (V): ~10

Apparent dimensions (V): 15′ × 8′

Did you know: Bubble Nebula is located just 11,000 light-years away toward the Cassiopeia constellation.