NGC 4818
| NGC 4818 | |
|---|---|
 NGC 4818 imaged by Hubble Space Telescope | |
| Observation data (J2000 epoch) | |
| Constellation | Virgo |
| Right ascension | 12h 56m 48.8829s[1] |
| Declination | −08° 31′ 30.906″[1] |
| Redshift | 0.003552 ± 0.000103 [1] |
| Heliocentric radial velocity | 1,065 ± 31 km/s[1] |
| Distance | 45.2 ± 14.2 Mly (13.9 ± 4.4 Mpc)[1] |
| Group or cluster | Virgo II Groups |
| Apparent magnitude (V) | 11.1[2] |
| Characteristics | |
| Type | SAB(rs)ab pec [1] |
| Size | ~56,000 ly (17.3 kpc) (estimated)[1] |
| Apparent size (V) | 4.3′ × 1.5′ [1] |
| Other designations | |
| IRAS 12542-0815, MCG -01-33-057, Mrk 9022, PGC 44191[1] | |
NGC 4818 is a spiral galaxy in the constellation Virgo. The galaxy lies about 45 million light years away from Earth, which means, given its apparent dimensions, that NGC 4818 is approximately 55,000 light years across.[1] It was discovered by William Herschel on March 3, 1786.[3]
NGC 4818 has an elliptical bulge with a bright nucleus. The galaxy has a bar which appears about 30 degrees offset from the makor axis of the bulge. Some loosely wrapped spiral arms emerge from the bulge. A faint disk with a low contrast broad spiral pattern is seen surrouding the bulge aligned with the major axis of the elliptical bulge.[4] The spectrum of the nucleus is similar with that of an HII region.[5] The total star formation rate is estimated to be 0.7 M☉ per year. The total gas mass is estimated to be 109.77 M☉ while the total star mass is about 1010.2 M☉.[6]
A. M. Garcia considers the galaxy to be a member of the NGC 4699 Group, or LGG 307. Other members of that group include NGC 4699, NGC 4700, NGC 4722, NGC 4742, NGC 4781, NGC 4790, and NGC 4802.[7] Makarov et al consider the galaxy to be a member of the Messier 104 Group, along with NGC 4802 and the Sombrero Galaxy among other members.[8] It is part of a Virgo II Groups, a chain of groups extending from the Virgo Cluster.[9]
Gallery
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NGC 4818 by Legacy Surveys
References
[edit]- ^ a b c d e f g h i j "Results for object NGC 4818". NASA/IPAC Extragalactic Database. NASA and Caltech. Retrieved 25 February 2025.
- ^ "Revised NGC Data for NGC 4818". spider.seds.org. Retrieved 30 March 2024.
- ^ Seligman, Courtney. "NGC 4818 (= PGC 44191)". Celestial Atlas. Retrieved 19 November 2018.
- ^ Eskridge, Paul B.; Frogel, Jay A.; Pogge, Richard W.; Quillen, Alice C.; Berlind, Andreas A.; Davies, Roger L.; DePoy, D. L.; Gilbert, Karoline M.; Houdashelt, Mark L.; Kuchinski, Leslie E.; Ramirez, Solange V.; Sellgren, K.; Stutz, Amelia; Terndrup, Donald M.; Tiede, Glenn P. (November 2002). "Near-Infrared and Optical Morphology of Spiral Galaxies". The Astrophysical Journal Supplement Series. 143 (1): 73–111. arXiv:astro-ph/0206320. Bibcode:2002ApJS..143...73E. doi:10.1086/342340.
- ^ Goulding, A. D.; Alexander, D. M. (21 September 2009). "Towards a complete census of AGN in nearby Galaxies: a large population of optically unidentified AGN". Monthly Notices of the Royal Astronomical Society. 398 (3): 1165–1193. arXiv:0906.0772. Bibcode:2009MNRAS.398.1165G. doi:10.1111/j.1365-2966.2009.15194.x.
- ^ Ramos Padilla, Andrés F; Ashby, M L N; Smith, Howard A; Martínez-Galarza, Juan R; Beverage, Aliza G; Dietrich, Jamie; Higuera-G., Mario-A; Weiner, Aaron S (31 October 2020). "The AGN contribution to the UV–FIR luminosities of interacting galaxies and its role in identifying the main sequence". Monthly Notices of the Royal Astronomical Society. 499 (3): 4325–4369. doi:10.1093/mnras/staa2813.
- ^ Garcia, A. M. (1 July 1993). "General study of group membership. II. Determination of nearby groups". Astronomy and Astrophysics Supplement Series. 100: 47–90. Bibcode:1993A&AS..100...47G. ISSN 0365-0138.
- ^ Makarov, Dmitry; Karachentsev, Igor (21 April 2011). "Galaxy groups and clouds in the local (z~ 0.01) Universe". Monthly Notices of the Royal Astronomical Society. 412 (4): 2498–2520. arXiv:1011.6277. Bibcode:2011MNRAS.412.2498M. doi:10.1111/j.1365-2966.2010.18071.x. S2CID 119194025. Retrieved 1 February 2025.
- ^ "The Virgo II Groups". www.atlasoftheuniverse.com. Retrieved 25 February 2025.
External links
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- NGC 4818 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images
- NGC 4818 on SIMBAD
