NGC 7020 is a barred lenticular galaxy located about 140 million light-years away in the constellation Pavo.[3][4] NGC 7020 was discovered by astronomer John Herschel on August 31, 1836.[5]
| NGC 7020 | |
|---|---|
 The ringed galaxy NGC 7020. | |
| Observation data (J2000 epoch) | |
| Constellation | Pavo |
| Right ascension | 21h 11m 20.1s[1] |
| Declination | −64° 01′ 31″.[1] |
| Redshift | 0.010677[1] |
| Heliocentric radial velocity | 3201 km/s[1] |
| Distance | 138 Mly (42.4 Mpc)[1] |
| Apparent magnitude (V) | 12.78[1] |
| Characteristics | |
| Type | (R)SA0^+(r)[1] |
| Size | ~110,000 ly (33.6 kpc) (estimated)[2] |
| Apparent size (V) | 3.7 x 1.8[1] |
| Other designations | |
| NGC 7021, ESO 107-13, PGC 66291[1] | |
Physical characteristics
editNGC 7020 has a large outer ring surrounding a bright inner hexagonal zone containing an inner ring and possibly a bar. The large outer ring is completely detached from the inner hexagonal zone of the galaxy and is dominated by numerous flocculent spiral features. The outer ring has an estimated diameter of 110,000 ly (33.6 kpc). The ring is knotty and bluer than the rest of the galaxy and shows where recent star formation is occurring in NGC 7020. The possible inner ring shows protruding features at the ends of its major axis therefore classifying it as a bar. The galaxy appears to be fairly free of ionized gas, which is not surprising for an early-type galaxy.[2][6]
Nearby galaxies
editNGC 7020 is member of a sparse group of galaxies that contains IC 5084, IC 5092, IC 5096, NGC 6943, NGC 7083, NGC 7096, NGC 7125, NGC 7126 and ESO 107-14.[7] However, NGC 7020 is not interacting with any other galaxy in the group.[8]
See also
edit- NGC 7098
- NGC 7013
- NGC 4429 galaxy in the Virgo Cluster with a similar structure
- List of NGC objects (7001–7840)
References
edit- ^ a b c d e f g h i "NASA/IPAC Extragalactic Database". Results for NGC 7020. Retrieved 2017-06-06.
- ^ a b 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. arXiv:1004.5063. Bibcode:2010AJ....139.2465G. doi:10.1088/0004-6256/139/6/2465. S2CID 119099302.
- ^ Rojas, Sebastián García. "Galaxy NGC 7020 - Galaxy in Pavo Constellation · Deep Sky Objects Browser". DSO Browser. Archived from the original on 2017-08-13. Retrieved 2017-06-07.
- ^ "Your NED Search Results". ned.ipac.caltech.edu. Retrieved 2017-09-23.
- ^ "New General Catalog Objects: NGC 7000 – 7049". cseligman.com. Retrieved 2017-04-15.
- ^ "NGC 7020 - (R)SAB(r?)0/a". Retrieved 2017-06-07.
- ^ Buta, R. (June 1990). "Weakly barred early-type ringed galaxies. III - The remarkable outer-ringed S0+ galaxy NGC 7020". The Astrophysical Journal. 356: 87–99. Bibcode:1990ApJ...356...87B. doi:10.1086/168819. ISSN 0004-637X.
- ^ Ronald, Buta (November 1990). "The ringed X-galaxy NGC 7020". NASA Conference Publication. 3098 (124): 189. Bibcode:1990NASCP3098..189B.
External links
edit- NGC 7020 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images