2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/10452Sillanpää, {\it et al.} (1996) have demonstrated that the AGN OJ287 has intensity peaks which recur with a period of about 12 years. I suggest that this is the result of the sweeping of a precessing relativistic beam across our line of sight. In analogy to Her~X-1 and SS433, precession is attributed to the torque exerted by a companion mass on an accretion disc. Secondary maxima observed 1.2 years after two of these peaks may be evidence of nodding motion.9 pp., tex, 0 figuresAstrophysicstext