Compact Symmetric Source 4C31.04

Compact Symmetric Sources (CSOs) are small sources with lobe emission on both sides of an active core. They are very similar to classical extended radio sources but have a much smaller linear size, less than 1 kiloparsec. The study of these objects is particularly interesting because the CSO properties are related to the young source ages, 10,000 to 100,000 years. Unifying evolutionary models have been proposed whereby CSOs evolve into CSS (Compact Steep Spectrum) sources and then into Fanaroff-Riley type II galaxies or possibly Fanaroff-Riley type I radio galaxies. 4C31.04 is a nearby CSO (at a redshift z = 0.0592) with a faint central core and a flat spectrum and two extended lobes.

Legacy Astronomical Images

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Legacy Astronomical Image

4C31.04

Gabriele Giovannini, et al.

Gabriele Giovannini, et al.

Very Long Baseline Array (VLBA)

1992-01-30

continuum

C

6 cm

5.0 GHz

RA 1:19:35.000, Dec: 32:10:50.100 (J2000)

Active Galactic Nuclei Series

Radio Galaxies Unit