Remarkable increase in the optical brightness of 1ES 1959

ATel #15778; K. Rosenlehner, J. Seufert, D. Scheuermayer, F. Molz, B. Mengelkamp, J. Ludwig, A. Lessing, D. Kuberek, B. Horst, F. Hemrich, M. Heidemann, O. Domann, L. Bertsch, N. Bader, T. Apell, E. Ankara, M. Feige, D. Reinhart, N. Zottmann, C. Lorey (all Friedrich-Koenig-Gymnasium / Hans-Haffner-Sternwarte) A. Scherbantin, K. Mannheim (Universitaet Wuerzburg), D. Elsaesser (TU Dortmund)
on 25 Nov 2022; 16:00 UT
Credential Certification: Dominik Elsaesser (dominik.elsaesser@tu-dortmund.de)

Tweet

The BL Lac type object 1ES 1959+650 (RA: 19 59 59.8520 Dec: +65 08 54.6525; ICRS J2000; z=0,048) underwent a rapid increase in optical brightness in R-band from 14.65mag (JD 2459897.2152) to 14.23mag (JD 2459908.3377) during the last few nights.
During 2022, the brightness of this blazar in the R-band ranged from about 14.6mag to 14.8mag, with a smaller increase in brightness in September and the first half of October to a maximum of 14.4mag around September 21. / 22. (JD 2459844.5).
From three Swift-XRT observations conducted from June 12 to June 14, 2022 (ATel #15433), a count rate of 10.5 - 14.5 cts/s was reported. During that time-frame, we however did not observe particular optical activity.
While the current brightness is well below that displayed by the object from 2016 to 2019, we do find the sharp increase to be noteworthy. 1ES 1959 may be entering a new phase of optical activity. Therefore, we encourage continued multiwavelength observations.

We report the following preliminary R-band magnitudes:
JD 2459889.3174: 14.617 ± 0.012
JD 2459894.3936: 14.572 ± 0.011
JD 2459895.2393: 14.628 ± 0.013
JD 2459897.2152: 14.649 ± 0.007
JD 2459906.4707: 14.324 ± 0.007
JD 2459907.1947: 14.269 ± 0.007
JD 2459908.2049: 14.240 ± 0.007
JD 2459908.3377: 14.229 ± 0.006
JD 2459908.5889: 14.242 ± 0.009


These measurements are carried out as part of the long-term AGN monitoring program of the Naturwissenschaftliches Labor fuer Schueler am Friedrich-Koenig-Gymnasium (FKG), the Universitaet Wuerzburg, and TU Dortmund with the 0.5m CDK-astrograph at the school and university observatory Hans-Haffner-Sternwarte in D-97265 Hettstadt (Germany).

NATUR­WISSEN­SCHAFT­LICHES LABOR FUER SCHUELER AM FKG E.V.