NGC 6185
Spiral radio galaxy in the constellation Hercules
From Wikipedia, the free encyclopedia
NGC 6185, also called UGC 10444, is a LINER and spiral galaxy of morphological type Sa.[1] It is at redshift z = 0.034304, equivalent to 152 million parsecs (496 million light-years) away, in the constellation of Hercules, and has an apparent B magnitude of 14.5.[1][2] The galaxy was discovered in April 1827 by British astronomer John Herschel.[3]
| NGC 6185 | |
|---|---|
PanSTARRS DR1 image of NGC 6185 | |
| Observation data (J2000 epoch) | |
| Constellation | Hercules |
| Right ascension | 16h 33m 17.83s |
| Declination | +35° 20′ 32.43" |
| Redshift | 0.034304 |
| Heliocentric radial velocity | 10108 |
| Distance | 492.9 mly (152.04 mpc) |
| Group or cluster | Abell 2199 |
| Apparent magnitude (B) | 14.5 |
| Characteristics | |
| Type | Sa |
| Mass | 295.1 billion M☉ |
| Size | 239,400 ly (73,410 pc) |
| Apparent size (V) | 1.2' x 0.9' |
| Other designations | |
| UGC 10444, KUG 1631+354, CGCG 196-077 | |
Physical properties
NGC 6185 is a massive spiral Sa galaxy in the galaxy cluster Abell 2199. It is 239,000 light-years (73,000 parsecs) across based on an angular diameter of 1.2 arcmin and a distance of 152 million parsecs (496 million light-years) away.[2] It has a stellar mass of 295.1×109 M☉ and is believed to be a starburst galaxy.[4]
It has an active galactic nucleus (AGN) that is also classified as a quasar[1] and is estimated to be extremely bright with a luminosity of 131.5×109 L☉.[4] The active galactic nucleus of NGC 6185 is powered by a 600-million-M☉ black hole accreting matter that is ejected far beyond the physical galaxy, forming its immense radio lobes.[4] The central black hole mass is high; however, it is expected for giant radio galaxies (GRGs) and is comparable to similar spiral-hosted radio galaxies such as J2345-0449.[4] It is possible that the active galactic nucleus is inactive and the radio structure is a remnant.[4]
In 2016, an ultraluminous X-ray source was discovered in NGC 6185. It was designated CXOU J163317.7+352018 and has an estimated luminosity of 57.9 million L☉.[5]
In 2022, it was found in the LOFAR Two-metre Sky Survey for giants (LoTSS) that NGC 6185 generated radio lobes spanning ~2.54 megaparsecs, making it the largest known spiral galaxy-hosted radio galaxy. It greatly surpasses the previous largest spiral radio galaxy, J2345-0449, which has an extent of ~1.63 megaparsecs.[4][6] The radio structure is a Fanaroff-Riley class II radio galaxy which are edge-brightened and far more luminous than their counterpart, and it is also a double lobed radio galaxy, so it is technically classified as a spiral DRAGN.[4] The total exact length of the radio structure is 2.544 million parsecs (8.30×106 ly), comparable to the Local Group and other small galaxy clusters.[6] This estimate is based on an angular diameter of 60 arcmin, which is the second-largest of any GRG.[6]
See also
- List of spiral DRAGNs
- Abell 2199 – the galaxy cluster NGC 6185 is located in