3C 20 | |
---|---|
Observation data ( J2000 epoch) | |
Constellation | Cassiopeia |
Right ascension | 00h 43m 08.84s [1] |
Declination | +52° 03′ 33.8″ [1] |
Redshift | 0.174 |
Distance | ~ 700 Mpc |
Apparent magnitude (V) | 19 [2] |
Characteristics | |
Type | E [1] |
Apparent size (V) | 76.8 × 76.8 arcsec² [3] (radiogalaxy) |
Other designations | |
DA 22, LEDA 2817481, 3C 20 |
3C 20 is a radio galaxy [4] located in the constellation Cassiopeia. It is one of largest known galaxies with a diameter of 850,000 ly (260 kpc). [a] The galaxy features a prominent double hotspot in its eastern lobe. An unusually low fraction of the flux lies within the radio core, which is suggested to be caused by a combination of factors, including jet orientation, synchrotron self-absorption and aging, as well as interactions with surrounding gas and dust. [5]