Astron. Astrophys. Suppl. Ser. 143, 357-368
Tuorla quasar monitoring
I. Observations of 1995-1997
S. Katajainen1 - L.O. Takalo1 - A. Sillanpää1 - K. Nilsson1 - T. Pursimo1 - M. Hanski1 - P. Heinämäki1 - E. Kotoneva1 - M. Lainela1 - P. Nurmi1 - H. Pietilä1 - R. Rekola1 - A. Riehokainen1 - P. Teerikorpi1 - E. Valtaoja1,2 - A. Lähteenmäki2
Send offprint request: S. Katajainen,
1 - Tuorla Observatory, Väisäläntie 20, FIN-21500 Piikkiö,
2 - Metsähovi Radio Observatory, Helsinki University of Technology,
FIN-02540 Kylmälä, Finland
Received March 30; accepted November 26, 1999
We present results of optical monitoring of quasars and
blazars obtained at Tuorla Observatory between September 1995 and May 1997.
The aim of our monitoring is to provide well sampled optical
light curves for quasar and blazar studies.
During the observing period the V
-band brightness of
S2 0109+224, 3C 66A, and ON 231 (W Comae)
reached some of the brightest values ever measured
for these objects. A strong outburst was observed in Mrk 421
and the large outburst, which was predicted earlier, in OJ 287 was
CTA 102 had over one magnitude outburst which happened
in a timescale of a few days. For OI 090.4 we measured one of the
-band brightness values ever.
Key words: galaxies: active -- BL Lacertae objects: general -- quasars: general
Copyright The European Southern Observatory (ESO)
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