Frankfurt Quasar Monitoring


PG 1553+113
Object data

  Cross-Identifications   TXS 1553+113, MG1 J155545+1110, 1553+113
  SDSS J155542.97+111124.4, QSO B1553+113
  87GB 155321.5+112002, 2E 1553.3+1120
  0FGL J1555.8+1110, HESS J1555+111
  RX J1555.7+1111, 1ES 1553+113, PG 1553+11
  Equat. coordinates   RA  15 55 43.1     DE  +11 11 24     (J2000)
  Constellation   Serpens (Caput)
  Type   BL Lac
  Redshift (2) (5)   z=0.360
  Distance (2) (3)
  1365 Mpc
  Total mag range (mv) (4)   13.5 - 15.3
  Catalog Magnitude   15. (1) (2)  /  14.8 B (5)
  Absolute Magnitude (1)   -26.8 MB
  Light Travel-Time (2)   3.819 × 109 yrs
(1) Véron-Cetty & Véron 2006, A&A 455, 776
(2) NASA/IPAC Extragalactic Database
(3) Co-Moving Radial Distance
(4) Literature
(5) CDS Strasbourg Database


Finding chart
1553+113_chart_fqm.jpg

Comparison stars

star B V Rc Ic (1)
2 14.524 (0.023) 13.828 (0.001)
13.435 (0.001) 13.078 (0.012)
1 14.566 (0.024) 13.920 (0.008) 13.558 (0.004) 13.242 (0.013)
3 14.243 (0.024) 13.406 (0.005) 12.915 (0.003) 12.454 (0.013)
4 15.746 (0.028) 14.508 (0.008) 13.774 (0.006) 13.166 (0.018)
5 13.505 (0.024) 12.832 (0.007) 12.461 (0.005) 12.130 (0.014)
7 15.117 (0.026) 14.167 (0.009) 13.632 (0.005) 13.184 (0.013)
8 13.920 (0.024) 13.108 (0.007) 12.689 (0.009) 12.330 (0.015)
comparison stars from Doroshenko et al. 2005, Ap, 48, 304

Colour chart
1553+113_sdss_fqm.jpg
Credit: SDSS  /  Size 13´× 13´ /  Chart by S. Karge

Light curve
1553+113_lc1808_fqm.jpg

Notes
PG 1553+113 is a bright BL Lac object in Serpens (Caput), about 5° E of Delta Ser and close to the constellation Hercules. PG 1553+113 was discovered as a blue stellar object by the Palomar-Green Bright Quasar Survey (PG) between 1976 and 1982. In the early 1980s, it was classified as a BL Lac object due to its featureless spectrum. Besides a long list of quasars, PG 1553+113 was the only BL Lacertae object that was discovered in the course of the Palomar-Green Bright Quasar Survey. Besides the optical and the radio, PG 1553+113 was also detected as both an X-ray source and as a TeV gamma-ray emitter.

PG 1553+113 is slightly variable between 13.5 mag and 15.3 mag in the optical. During recent years, it has been a bright stellar object. Therefore, it is well suited for visual observers with telescopes of 8-inch and 10-inch of aperture. Due to its large distance of nearly 4×109 light-years it remains a stellar object in any kind of telescope.
CCD observers, as well as visual observers, shall use the comparison stars given above.
____________

An interesting deep sky object is located only 4° to the east: IC 4593, a bright planetary, also dubbed the "White-eyed Pea". The name refers to the high surface brightness of this planetary and the whitish-green colour of the small nebulous halo which surrounds the bright central star. Do not hesitate to use high powers! This planetary responds well to both UHC- and O-III filters.

Obervers who like to have look at another BL Lac object may turn to H 1722+119, a variable object about 22° E, at a distance of nearly 2×109 light-years.
Another bright 15-mag quasar is MRK 877 at a distance of more than 1×109 light-years, 8.6° to the NE.


Literature
Aleksić, J., et al. 2012, ApJ, 748, 46; PG 1553+113: Five Years of Observations with MAGIC.
Carangelo, N., Falomo, R., et al. 2003, A&A, 412, 651; Optical spectroscopy of BL Lac objects: new redshifts and
     mis-identified sources.
Doroshenko, V.T., Sergeev, S.G., et al. 2005, Ap, 48, 304D; BVRI CCD-Photometry of Comparison Stars in the
     Neighborhoods of Galaxies with Active Nuclei. II
Falomo, R., Treves, A., 1990, PASP, 102, 1120; PG 1553+11 - A bright optically selected BL Lacertae object.
Green, R.F., Schmidt, M., Liebert, J., 1986, ApJS, 61, 305; The Palomar Green Catalogue of Ultraviolet-Excess Stellar
     Objects.
Karge, S.; Helle Quasare für 8- bis 10-Zoll Teleskope. Ein Beobachtungsführer zur visuellen Beobachtung von
     Quasaren und BL Lacertae Objekten; Frankfurt 2005.
Perlman, E.S., Stocke, J.T., et al. 1996, ApJS, 104, 251; The Einstein Slew Survey.
Pica, A.J., Smith, A.G., et al. 1988, AJ, 96, 4; Long-term optical behavior of 144 compact extragalactic objects:
     1969-1988.
Snellen, I.A.G., et al. 2002, MNRAS, 329, 4; Automated optical identification of a large complete northern hemisphere
     sample of flat-spectrum radio sources with S6 cm > 200 mJy.
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.
Wenzel, K., Düskau, W., 2003, SuW 2/03, 60; BL-Lacertae-Objekte - Eine Herausforderung für den Amateur.




Links:

Landessternwarte Heidelberg

Chara/PEGA

Sloan Digital Sky Survey


© 2018-08-18 by Stefan Karge





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