Frankfurt Quasar Monitoring


3C 454.3
Object data

  Cross-Identifications  PKS 2251+158, 4C 15.76, OY+185, DA 586, 2251+158
  2EG J2253+1615, GEV J2253+1622, EGRET J2253+1615
  NRAO 701, VRO 15.22.05, 2MASSi J2253577+160853
  87GB 225129.8+155251, H 2251+158, LEDA 2819327
  TXS 2251+158, KUV 22515+1553, RX J2253.9+1608
  WMAP J2254+1608, SWIFT J2253.9+1608, RBS 1911  

  Equat. coordinates   RA  22 53 57.7     DE  +16 08 53     (J2000)
  Constellation   Pegasus
  Type   QSO
  Redshift   z=0.859
  Distance (2) (3)
  2869 Mpc
  Total mag range (mv) (4)   12.3 - 17.2
  Catalog Magnitude (1)   16.10
  Absolute Magnitude (1)   -27.3 MB
  Light Travel-Time (2)   6.914 × 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
2251+158_chart_fqm.jpg

Comparison stars

star  B V Rc Ic
A ----
15.86 (0.09)
15.32 (0.09)
14.80 (0.06)
B ----
15.21 (0.06)
14.73 (0.05)
14.31 (0.05)
E ---- 15.76 (0.09)
14.92 (0.08) 14.26 (0.08)
H
---- 13.65 (0.04)
13.10 (0.04)
12.58 (0.04)
C1 ---- 15.67 (0.06)
15.27 (0.06)
14.71 (0.06)
3 15.292 (0.025)
14.402 (0.012)
13.951 (0.003)
13.528 (0.004)
10 18.334 (0.958)
17.217 (0.164)
16.589 (0.088)
15.829 (0.030)
11 16.346 (0.610)
16.581 (0.031) 16.132 (0.055)
15.556 (0.038)
20 16.584 (0.125) 15.709 (0.029) 15.156 (0.026) 14.528 (0.051)
21 18.667 (0.679) 16.891 (0.156) 15.939 (0.073) 15.109 (0.062)
comparison stars 3-21 from Gonzŕlez-Pérez et al. 2001, AJ, 122, 2055 (selection)
comparison stars A-H from Fiorucci et al. 1998, PASP, 110, 105
Light curve
2251+158_lc1812_fqm.jpg

Colour chart
2251+158_sdss_fqm.jpg
Credit: SDSS  /  Size 13´× 13´ /  Chart by S. Karge

Notes
Quasar 3C 454.3 is a violently variable object located in Pegasus, 2.7° WSW of Alpha Pegasi. 3C 454.3 is a high polarization quasar (HPQ) and one of the most violent variable sources in the sky. The strong variability ranges from radio to gamma wavelength. This OVV is very active with a total range of about 5 magnitudes (!) in the optical. The optical events show fast, spike-like flares with sharply raising and falling fluxes.
3C 454.3 was discovered as a radio source during the 3. Cambridge Radio Survey (3C) in 1959. Since then, this quasar has been cataloged by several other radio surveys (e.g. 4C, PKS, 87GB, TXS). In the early 1960s, a faint blue stellar object of 18-mag was found as the optical counterpart, which turned out to be variable in both radio and optical wavelength. The first reliable redshift of z=0.859 was measured in 1967, which corresponds to a light travel time of nearly 7 Gyrs. 3C 454.3 has also been detected as an X-ray source since 1980 and as a source of gamma-rays since the early 1990s.
Quasar 3C 454.3 is a violently variable object with a total range of about 5 magnitudes in the optical. For visual observers with a 10- to 12-inch telescope or larger this is a difficult target, as it will only be visible during active state. 3C 454.3 appears as a stellar object even in large aperture telescopes. CCD observers, as well as visual observers, shall use the comparison stars given above. Other photometric sequences were published by Angione (1971), Raiteri et al. (1998) and Smith et al. (1998).
____________

Quasar 3C 454.3 is located in Pegasus, 2.7° WSW of Alpha Pegasi, also known as Markab. Turning the telescope 4.6° to the SE shows 11.7-mag NGC 7479, a very interesting face-on spiral with two prominent extended spiral arms. The core of NGC 7479 is also known as an AGN with Seyfert-1 spectrum.
By heading 5° further to the SE we reach the Pegasus-I galaxy cluster, which is dominated by the two bright ellipticals NGC 7619 (12.1 mag) and NGC 7626 (12.2 mag). A 10-inch telescope at high powers shows about 8 additional members of Pegasus-I galaxy cluster. Finally, one deep sky showpiece in southern Pegasus shall not be missed: globular cluster M15. This 6.2-mag globular is one of the brightest globular clusters in the northern sky and is located some 20° WSW of 3C 454.3. M15 appears bright and large with a very dense core. Inside M15, large aperture telescopes may reveal a very special object: Pease 1, a faint planetary nebula, only 3” in diameter.

A more challenging deep sky object is another quasar, MRK 304, a bright 14-mag object at a distance of about 0.8×109 light-years, 9° WSW of 3C 454.3.


 Literature
Altschuler, D.R., Gurvits, L.I., et al. 1995, A&AS, 114, 197; The Centi-Arcsecond Structure of 16 Low-Frequency Variable
     Sources at 92 cm.
Angione, R.J. 1971, AJ, 76, 412; Photoelectric Sequences for the Brighter QSO´s.
Blom, J.J., Bloemen, N., et al. 1995, A&A, 295, 330; COMPTEL Gamma-Ray Observations of the Quasars CTA 102 and
     3C 454.3.
Fiorucci, M., Tosti, G., Rizzi, N. 1998, PASP, 110, 105; VRI Photometry of Stars in the Fields of 16 Blazars.
Gonzŕlez-Pérez, J.N., et al. 2001, AJ, 122, 2055; Optical and Near-Infrared Calibration of AGN Field Stars: An All-Sky
     Network of faint Stars calibrated on the Landolt System.
Jorstad, S.G., Marscher, A.P., et al. 2010, ApJ, 715, 362; Flaring Behavior of the Quasar 3C 454.3 across the
     Electromagnetic Spectrum.
Lynds, C.R. 1967, ApJ, 147, 837L; New Spectroscopic Observations of Twenty Quasi-Stellar Sources.
Pauliny-Toth, I.I.K., Kellermann, K.I. 1966, ApJ, 146, 634; Variations in the Radio-Frequency Spectra of 3C 84, 3C 273,
     3C 279, and Other Radio Sources.
Raiteri, C.M., Villata, M., et al. 1998, A&AS, 130, 495; BVR Photometry of Comparison Stars in selected Blazar Fields. II.
Raiteri, C.M., Villata, M., et al. 2011, A&A 534, 87; The long-lasting activity of 3C 454.3. GASP-WEBT and satellite
     observations in 2008–2010.
Smith, P.S., Balonek, T.J. 1998, PASP, 110, 1164; Photometric Calibration of Stars in the Fields of Selected BL Lacertae
     Objects and Quasars.
Spinrad, H., Djorgovski, S., et al. 1985, PASP, 97, 932; A Third Update of the Status of the 3CR Sources - Further
     New Redshifts and New Identifications of Distant Galaxies.
Steinicke, W.; Katalog heller Quasare und BL Lacertae Objekte; Umkirch 1998.
Tananbaum, H., Wardle, J.F.C., et al. 1983, ApJ, 268, 60; X-ray Studies of Quasars with the Einstein Observatory.
     III. The 3CR sample.
Thompson, D.J., Bertsch, D.L., et al. 1995, ApJS, 101, 259; The Second EGRET Catalog of High-Energy Gamma-Ray
     Sources.
Villata, M., Raiteri, C.M. 1997, A&AS, 121, 119; Optical Photometric Monitoring of Gamma-Ray Loud Blazars.
     I. Observations from November 1994 to November 1995.
Xie, G.Z., Li, K.H., et al. 2001, ApJ, 548, 200; Search for Short Variability Timescale of the GEV Gamma-Ray-Loud
     Blazars.

 


Links:

Landessternwarte Heidelberg (1)

Landessternwarte Heidelberg (2)

Chara/PEGA

Hamburg Quasar Monitoring

Sloan Digital Sky Survey

AAVSO

VSNET Alert 17367: Quasar 3C 454.3 in outburst (6/2014)

Distant Blazar 3C 454.3 in Outburst (Universe Today)


© 2018-12-28 by Stefan Karge






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