Astronomy:ESO 198-13
| ESO 198-13 | |
|---|---|
 Ring galaxy ESO 198-13. | |
| Observation data (J2000 epoch) | |
| Constellation | Eridanus |
| Right ascension | 02h 29m 16.1s[1] |
| Declination | −48° 29′ 29″[1] |
| Redshift | 0.018186/5452 km/s[1] |
| Distance | 237,147,400 ly |
| Apparent magnitude (V) | 13.64 |
| Characteristics | |
| Type | (R')SA(r)ab[1] |
| Size | ~162,773 ly (estimated) |
| Apparent size (V) | 1.7' x 1.2[1] |
| Notable features | Multiple-ringed Hoag-type galaxy |
| Other designations | |
| PGC 9463 [1] | |
ESO 198-13 is a ring galaxy with multiple ring-like structures[2] located about 240 million light-years away[3] in the constellation Eridanus.[4]
Physical characteristics
This galaxy has three ring structures. There is a small bright inner ring located close to the nucleus. This feature has been interpreted as a nuclear ring due to being similar to the nuclear rings in a barred spiral galaxy (e.g. NGC 1512, NGC 4314). Also this ring has a diameter of 15,527.12 light-years (4.76 kpc) which is larger than the average diameter of a nuclear ring (4,893 light-years/1.5 kpc). Surrounding the nuclear ring, a flocculent inner ring with a diameter of 54,801.6 light-years (16.8 kpc) can be found. It appears to be made of a very tightly wound spiral arm. It also could be a superposition of two rings offset from each other. Outside of the flocculent inner ring, there is a very large and faint outer ring with a diameter of 162,773.8 light-years (49.9 kpc).[2]
See also
- Hoag's object
- PGC 100174
- List of ring galaxies
- Cartwheel Galaxy
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 "NASA/IPAC Extragalactic Database". Results for ESO 198-13. http://nedwww.ipac.caltech.edu/.
- ↑ 2.0 2.1 Grouchy, R. D.; Buta, R. J; Salo, H.; Laurikainen, E. (3 May 2010). "Ring Star Formation Rates in Barred and Nonbarred Galaxies". The Astronomical Journal 139 (6): 2465–2493. doi:10.1088/0004-6256/139/6/2465. Bibcode: 2010AJ....139.2465G.
- ↑ "Your NED Search Results". http://ned.ipac.caltech.edu/cgi-bin/objsearch?objname=ESO+198-13&extend=no&hconst=73&omegam=0.27&omegav=0.73&corr_z=1&out_csys=Equatorial&out_equinox=J2000.0&obj_sort=RA+or+Longitude&of=pre_text&zv_breaker=30000.0&list_limit=5&img_stamp=YES.
- ↑ "Principal Galaxy Catalog (PGC) Objects 9000 - 9499" (in en-US). http://cseligman.com/text/atlas/pgc09.htm.
External links
- ESO 198-13 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images
- The de Vaucouleurs Atlas of Galaxies entry on ESO 198-13
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