X-ray analysis of a stellar bubble

"An XMM-Newton EPIC image (above) and an optical image with X-ray imagery superimposed (below) of the northwest quadrant of the Wolf-Rayet bubble S308. Color correspondence: red, Hydrogen-alpha; green, Oxygen[III]; blue: X-rays."

"S308 is a circumstellar bubble blown by the star HD 50896. It is one of only two single-star bubbles that show detectable diffuse X-ray emission. The diffuse X-ray emission shows a limb-brightened morphology, with a clear gap extending from the outer edge of the diffuse X-ray emission to the outer rim of the nebular shell."

See also:
"Massive stars live fast, blow hard and die young," a document in which you will find the full-frame image of the circumstellar bubble featured above.