Astronomy:NGC 2721
| NGC 2721 | |
|---|---|
 NGC 2721 imaged by Legacy Surveys | |
| Observation data (J2000 epoch) | |
| Constellation | Hydra |
| Right ascension | 08h 58m 56.5367s[1] |
| Declination | −04° 54′ 06.677″[1] |
| Redshift | 0.012399±0.00000900[1] |
| Helio radial velocity | 3,717±3 km/s[1] |
| Distance | 190.90 ± 7.29 Mly (58.531 ± 2.235 Mpc)[1] |
| Apparent magnitude (V) | 12.5[1] |
| Characteristics | |
| Type | SB(rs)bc pec[1] |
| Size | ~133,200 ly (40.83 kpc) (estimated)[1] |
| Apparent size (V) | 2.3′ × 1.6′[1] |
| Other designations | |
| IRAS 08564-0442, MCG-01-23-015, PGC 25231[1] | |
NGC 2721 is a barred spiral galaxy in the constellation of Hydra. Its velocity with respect to the cosmic microwave background is 4,028±22 km/s, which corresponds to a Hubble distance of 193.8 ± 13.6 Mly (59.41 ± 4.17 Mpc).[1] Additionally, 13 non-redshift measurements give a similar mean distance of 190.90 ± 7.29 Mly (58.531 ± 2.235 Mpc).[2] It was discovered by German-British astronomer William Herschel on 1 February 1786.[3][4]
NGC 2721 is a Seyfert II galaxy, i.e. it has a quasar-like nucleus with very high surface brightnesses whose spectra reveal strong, high-ionisation emission lines, but unlike quasars, the host galaxy is clearly detectable.[5][6]
Supernova
One supernova has been observed in NGC 2721:
See also
References
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 "Results for object NGC 2721". NASA and Caltech. https://ned.ipac.caltech.edu/byname?objname=NGC+2721.
- ↑ "Distance Results for NGC 2721". NASA. https://ned.ipac.caltech.edu/cgi-bin/nDistance?name=NGC+2721.
- ↑ Herschel, William (1789). "Catalogue of a Second Thousand of New Nebulae and Clusters of Stars; with a Few Introductory Remarks on the Construction of the Heavens". Philosophical Transactions of the Royal Society of London 79: 212–255. doi:10.1098/rstl.1789.0021. Bibcode: 1789RSPT...79..212H.
- ↑ Seligman, Courtney. "New General Catalogue Objects: NGC 2721". https://cseligman.com/text/atlas/ngc27.htm#2721.
- ↑ Chen, Yan-Ping; Zaw, Ingyin; Farrar, Glennys R.; Elgamal, Sana (2022). "A Uniformly Selected, Southern-sky 6dF, Optical AGN Catalog". The Astrophysical Journal Supplement Series 258 (2): 29. doi:10.3847/1538-4365/ac4157. Bibcode: 2022ApJS..258...29C.
- ↑ "NGC 2721". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=NGC+2721.
- ↑ "SN 2024xjl". IAU. https://www.wis-tns.org/object/2024xjl.
External links
- NGC 2721 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images
Coordinates: 
08h 58m 56.5367s, −04° 54′ 06.677″
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