to confine the radio source. It may also be that the larger amounts of cold gas in spiral galaxies in some way disrupts or stifles a forming jet. To date there is no compelling single explanation for the observations.

However, since the discovery of the exotic radio galaxy Speca in the year 2011 the number of large-scale radio galaxies hosted in disk/spiral galaxies have been steadily growing. The first such odd-ball radio galaxy was discovered in 1998, namely J0313-192