PKS 2155-304

PKS 2155-304
Image of PKS 2155-304 obtained in R band at ESO-NTT
Observation data (Epoch J2000)
ConstellationPiscis Austrinus
Right ascension21h 58m 52.0651817803s
Declination−30° 13′ 32.120657891″
Redshift0.116
Distance1.5 Gly
TypeBL Lac
Apparent magnitude (V)13.09
Other designations
QSO B2155-304,
See also: Quasar, List of quasars

PKS 2155-304 is a BL Lac object, a galaxy hosting a type of blazar. It is a strong emitter from radio to high-energy frequencies.

PKS 2155-304 is at redshift z = 0.116 (Falomo, Pesce & Treves 1993)[full citation needed]. It is one of the brightest and most studied BL Lacs, one of the first identified through X-ray observations.[1]

  1. ^ Aharonian, F.; et al. (2007). "An Exceptional Very High Energy Gamma-Ray Flare of PKS 2155-304". The Astrophysical Journal. 664 (2): L71–L78. arXiv:0706.0797. Bibcode:2007ApJ...664L..71A. doi:10.1086/520635. S2CID 119319369.