SIMBAD references

OJ 287 is one of the best studied blazars. It is also a prime target in our long-term blazar monitoring program carried out with the 1.56 m telescope at the Sheshan Station of the Shanghai Astronomical Observatory, China. Here, we present optical photometry results of V, R, and I passbands of the BL Lacertae object OJ 287 (0851+202) carried out from 2002 January to 2007 February. The largest variations of ΔV = 1.96 mag (14.01-15.97 mag), ΔR = 2.36 mag (13.39-15.75 mag), and ΔI = 1.95 mag (12.79-14.74 mag) were detected in our observations. Intraday variation timescales of ∼10 minutes to 2 hr were detected in optical passbands.