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] |
| Heliocentric 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, 2MASX J08585649-0454072, 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
- ^ a b c d e f g h i j k "Results for object NGC 2721". NASA/IPAC Extragalactic Database. NASA and Caltech. Retrieved 19 January 2026.
- ^ "Distance Results for NGC 2721". NASA/IPAC Extragalactic Database. NASA. Retrieved 19 January 2026.
- ^ 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. Bibcode:1789RSPT...79..212H. doi:10.1098/rstl.1789.0021.
- ^ Seligman, Courtney. "New General Catalogue Objects: NGC 2721". Celestial Atlas. Retrieved 19 January 2026.
- ^ 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. arXiv:2111.13217. Bibcode:2022ApJS..258...29C. doi:10.3847/1538-4365/ac4157.
- ^ "NGC 2721". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 19 January 2026.
- ^ "SN 2024xjl". Transient Name Server. IAU. Retrieved 19 January 2026.
External links
- Media related to NGC 2721 at Wikimedia Commons
- NGC 2721 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images