This x-ray image of Casseiopeia A shows that the youngest remnant of a supernovaor star explosionin our galaxy acts like a near light speed pinball machine, accelerating electrons at extremely high energy levels.
An expanding shock wave where the acceleration takes place is seen in blue in the image above. Other colors show debris from the destroyed star that created the remnant 325 years ago.
Released on November 15, the image is helping scientists understand the origins of high-energy particles known as cosmic rays, which bombard the Earth. Supernova remnants such as "Cas A" may be one source of such rays.