C11 · nebula

Bubble Nebula

The Bubble Nebula, also known as NGC 7635, Sharpless 162, or Caldwell 11, is an H II region emission nebula in the constellation Cassiopeia.

RA23h 20m 45sDec+61° 12' 44"

Image: NASA, ESA, Hubble Heritage Team. Public domain, via Wikimedia Commons.

Identity & coordinates

Identification

Primary designation: C11
All designations: C11 · NGC 7635 · Bubble Nebula
Object type: Nebula
Constellation: Cassiopeia
Best viewing: Autumn · Winter

Coordinates & physical

Right ascension (J2000): 23h 20m 45s
Declination (J2000): +61° 12' 44"
Apparent magnitude (V): —
Distance: —

III

Visibility tonight

The science

The Bubble Nebula, also known as NGC 7635, Sharpless 162, or Caldwell 11, is an H II region emission nebula in the constellation Cassiopeia. It lies close to 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 (BD+60°2522). The nebula is near a giant molecular cloud which contains the expansion of the bubble nebula while itself being excited by the hot central star, causing it to glow. It was discovered in November 1787 by William Herschel. The star BD+60°2522 is thought to have a mass of about 44 M☉.

Summary adapted from Wikipedia · CC-BY-SA-4.0