A second correlated radio-optical outburst in the BL Lacertae-type quasi-stellar object 0235+164

Evidence for a correlation between a recent radio outburst in 0235+164 and the optical outburst of early 1979 is presented. The simultaneous peaks of the optical and radio emission have the same pattern as the 1975 outburst, implying a common energy source for both the radio and optical radiation. Measurements at five radio frequencies show that the radio spectrum has remained very flat at all epochs.