PK 0048–09: a Possible Radio Variable Galaxy

Planets, Stars and Stellar Systems

“…Another important property of AGN is their variability, a property first discovered in the late 1960s (Cannon et al 1968;Kinman 1968;Pacholczyk and Wyemann 1968;Barnes 1968;Selove 1969;Zaitseva and Lyutyi 1969;Babadzhanyants and Hagen-Thorn 1969) in the optical, and a couple years later in the radio (Stull 1970;Ross 1970). This variability has since been found to extend to all wavebands (see Ulrich et al 1997 for a review), in both continuum and line emission.…”