Frankfurt Quasar Monitoring


S2 0109+22
Object data

  Cross-Identifications   GC 0109+22, TXS 0109+224, QSO B0109+224
  PKS 0109+224, GB6 B0109+2228, 0109+224
  1RXS J011205.2+224452, RX J0112.0+2244
  87GB 010923.5+222858, RGB J0112+227
  2E 0109.3+2228, 0FGL J0112.1+2247
  Equat. coordinates   RA  01 12 05.8     DE  +22 44 39     (J2000)
  Constellation   Pisces
  Type   BL Lac
  Redshift (2)   z=0.265
  Distance (2) (3)   1023 Mpc
  Total mag range (mv) (4)   13.86 - 18.08
  Catalog Magnitude (1)   15.66
  Absolute Magnitude (1)   --- MB
  Light Travel-Time (2)   2.968 × 109 yrs
(1) Véron-Cetty & Véron 2006, A&A 455, 776
(2) NASA/IPAC Extragalactic Database
(3) Co-Moving Radial Distance
(4) Literature


Finding chart
0109+224_chart_fqm.jpg

Comparison stars

star  B V Rc Ic
A 12.142 11.582 --- ---
B 13.251 12.511 12.111 11.761
C 14.042 13.372 --- ---
D 14.902 14.152 --- ---
E 15.191 14.451 14.091 ---
F 16.301 15.281 14.721 14.221
G 16.211 15.291 14.941 14.601
H 16.022 15.472 --- ---
I 16.322 15.752 --- ---
(1) comparison stars from Ciprini et al. 2003, A&A, 400, 487
(2) comparison stars from Miller et al. 1983, AJ, 88, 1301

Colour chart
0109+224_color_fqm.jpg
Credit: DSS2  /  Size 14´× 14´ /  Chart by S. Karge


High resolution images of S2 0109+22
0109+224_sdss_fqm.jpg
Credit: SDSS / Size 3´× 3´
This image shows the star-like
host galaxy
of S2 0109+22
0109+224_nilsson_fqm.jpg
Credit: Nilsson et al. (2003) / Size 26.6" × 26.6"
R-band image by the Nordic Optical Telescope (image inverted)


Light curve
0109+224_lc2301_fqm.jpg

Notes
The BL Lac object S2 0109+22 is a strong radio source in northern Pisces, located between the two stars Phi (85) Psc and Chi (84) Psc. The designation S2 0109+22 refers to the 2. Strong Source Catalog (S2), where this object was discovered as a radio source in the late 1960s. Since then, it has been catalogued by various other radio surveys. In 1976, the optical counterpart of this radio source was identified with a stellar object of 15.5 mag. Follow-up spectroscopic investigations revealed a continuous spectrum. Together with the strong optical polarization, S2 0109+22 was classified as a BL Lac-type object. It was not until 2008 when the first accurate redshift was published. The new redshift of z=0.265 corresponds to a light travel time of about 3 Gyrs. Besides the optical and radio, S2 0109+22 has been detected as a source of both X-ray and gamma emissions, too.

The most interesting feature about
S2 0109+22 is its large optical variability of more than 4 magnitudes. On average, the brightness ranges between about 14.8 mag and 15.4 mag. Visual observers will recognize S2:0109+22 as a stellar object. At maximum brightness, telescopes of 8- to 10-inch of aperture are fine, but usually observers need an aperture of 12- to 14-inches or larger to detect this BL Lac object in the eyepiece.
____________

Right next to S2 0109+22, only 6´ to the WSW, observers may like to test their skills with double star WDS 01117+2243 (= COU 147 = TYC 7.58-mag). This tight double consists of a 7.1-mag primary and an 11.8-mag companion, separated by a challenging 3.4". You find the WDS-double at the position of the 7.58-mag star in the lower right of the finding chart.
Deep sky observers find two bright face-on spirals in the near vicinity: The showpiece galaxies M 74 (9.0° SE) and M:33 (9.4° NE).
Those observers who like to focus on more very old quasi-stellar photons may turn to quasar I Zw 1, a bright 14-mag object at a distance of about 0.7×109 light-years, 11° SE of S2 0109+22.



Literature
Ciprini, S., Tosti, G., et al. 2003, A&A, 400, 487; Optical variability of the BL Lacertae object GC 0109+224.
Falomo, R., Scarpa, R., et al. 1994, ApJS, 93, 125; Optical Spectrophotometry of Blazars.
Karge, S.; Helle Quasare für 8- bis 10-Zoll Teleskope. Ein Beobachtungsführer zur visuellen Beobachtung von Quasaren
    und BL Lacertae Objekten; Frankfurt 2005.
Katajainen, S., Takalo, L.O., et al. 2000, A&AS, 143, 357; Tuorla quasar monitoring. I. Observations of 1995-1997.
Miller, H.R., Mullikin, T.L., et al. 1983, AJ, 88, 1301; Photoelectric comparison sequences in the fields of four
     BL Lacertae objects.
Nilsson, K., Pursimo, T., et al. 2003, A&A, 400, 95; R-band imaging of the host galaxies of RGB BL Lacertae objects.
Owen, F.N., Mufson, S.L. 1977, AJ, 82, 776; Extragalactic sources with strong Millimeter-Wave Emission.
Pica, A.J. 1977, AJ, 82, 12; Optical and radio properties of a newly discovered BL Lac object.
Pica, A.J., Pollock, J., Smith, A., et al. 1980, AJ, 85, 1442; Long-term optical behavior of 114 extragalactic sources.
Pica, A.J., Smith, A.G., et al. 1988, AJ, 96, 4; Long-term optical behavior of 144 compact extragalactic objects:
     1969-1988.
Puschell, J.J., Stein, W.A. 1980, ApJ, 237, 331; Observations of strongly polarized extragalactic sources.
Steinicke, W.; Katalog heller Quasare und BL Lacertae Objekte; Umkirch 1998.
Villata, M., Raiteri, C.M., et al. 1997, A&AS, 121, 119; Optical photometric monitoring of gamma-ray loud blazars. I.
Wills, B.J., Wills, D. 1979, ApJS, 41, 689; Spectroscopy of 125 QSO Candidates and Radio Galaxies.
Véron-Cetty, M.-P., Véron, P. 2001, A&A 374, 92; A Catalogue of Quasars and Active Nuclei: 10th edition.
Véron-Cetty, M.-P., Véron, P. 2003, A&A 412, 399; A Catalogue of Quasars and Active Nuclei: 11th edition.
Véron-Cetty, M.-P., Véron, P. 2006, A&A 455, 776; A Catalogue of Quasars and Active Nuclei: 12th edition.
Véron-Cetty, M.-P., Véron, P. 2010, A&A 518, 10; A Catalogue of Quasars and Active Nuclei: 13th edition.
Xie, G.Z., Li, K.H., et al. 1992, ApJS, 80, 683; CCD Photometry of 14 BL Lacertae objects and theoretical model.




Links:

Landessternwarte Heidelberg

Chara/PEGA

AAVSO

Sloan Digital Sky Survey


© Stefan Karge  /  last obs. 2023-01-25




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