PKS 0521-365

PKS 2155-304 is one of the brightest active galaxies in the sky. The source (BL Lac object) is a strong emitter from radio to gamma frequencies. The object is at z = 0.116.

Optical image of the BL Lac object PKS 2155-304 (brightest object) obtained in R filter with ESO-NTT. Surrounding objects are close companion galaxies. Image was partly deconvolved for proper point spread function (PSF) to enhance features close to the bright nucleus.

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