The outer radio halo: Typical of atypical radio sources?

The outer radio halo of M 87 is one of an unusual class of radio halo sources attached to cluster-center galaxies in cooling cores. The M 87 halo appears to be a young source, partially mixed with the ambient thermal plasma, expanding rather like a bubble into that plasma. The radio jet provides a significant energy source to the thermal core plasma. In turn, flows in the X-ray emitting plasma appear to disrupt the radio jet and account for formation of the radio halo.