The Cosmic Bubble

Located on the northern boundary of Cassiopiea and at a distance of about 11,000 llight years, the "bubble"  is generated by a stellar wind of fierce radiation from an embedded type O star at its centre. This giant star is 100,000 more luminous thab our sun and about 45 times as massive. Its violent outpouring has blown out a 10 light year diameter structure of glowing gas in the surrounding, denser molecular cloud.

Photographed in the SII/Ha/OIII "Hubble Palette" colours, this image represents a total of about 3 hours imaging data.