Sharpless 308: Star Bubble . ... Credit Copyright: Jeff Husted Explanation: Blown by fast winds from a hot, massive star, this cosmic bubble is huge. ... The massive star that created the bubble, a Wolf-Rayet star , is the bright one near the center of the nebula. Wolf-Rayet stars have over 20 times the mass of the Sun and are thought to be in a brief, pre-supernova phase of massive star evolution. ... NASA Web Site Statements, Warnings, and Disclaimers . NASA Official: Jay Norris. ...