What the Wild Things Are

Active galactic nuclei are extremely compact and highly energetic objects, and the mechanisms that produce their radiative emissions at short wavelengths are the subject of debate. In his research commentary, Buckley discusses results presented in the same issue by [Mannheim][1] in which the acceleration of protons is suggested as the source. Buckley puts the work in context with the alternative scenario involving an electron mechanism. [1]: http://www.sciencemag.org/cgi/content/short/279/5351/684