Taken by: Bob Finnigan and Lee Green
Exposure: 10-10-10-10 HaRGB
Description: Here's the Bubble Nebula next to the M52 open cluster in Cassiopeia. While M52 is a mature open cluster, the Bubble Nebula may be the first star of a new cluster. The bubble is formed by a star that is blowing away the material from which it was formed.