This wide-field image contains the area where a team of researchers confirmed that cosmic rays from our galaxy are very efficiently accelerated in the remnants of exploded stars. The red line guides the eye to various regions where the remnants of the stellar explosion are most visible. The boxed area contains an insert of data from the VLT and Chandra. This region, named RCW 86, is centered on the position where a star exploded in 185 AD. The field of view is 4 degrees across with north to the top and east to the left.