•Compact Sources (arcsecond scales and smaller)
•Extended Sources (Fanaroff-Riley 1974 classes) and can be very large (many arcminutes, up to Mpc)
–FR I, tend to be lower power, continuous, jets
•BL Lacs, radio galaxies
–FR II, higher power, edge-brightened lobes
•Quasars, radio galaxies
–Other stuff.
More messes, oh yes! Messes
in deep space.
–
•Optical IDs
–Tough game historically – point sources,
(elliptical) galaxies