NGC 3021
| NGC 3021 | |
|---|---|
 NGC 3021 (right of center) as seen by theHST | |
| Observation data (J2000epoch) | |
| Constellation | Leo Minor[1] |
| Right ascension | 09h50m57.146s[2] |
| Declination | 33° 33′ 12.94″[2] |
| Redshift | 0.00514±0.000013[3] |
| Heliocentric radial velocity | 1,537±4 km/s[4] |
| Galactocentric velocity | 1,502±4 km/s[4] |
| Distance | 92.8Mly(28.44Mpc)[4] |
| Apparent magnitude(V) | 10.88[3] |
| Apparent magnitude(B) | 12.54[4] |
| Absolute magnitude(V) | −21.25[3] |
| Characteristics | |
| Type | SA(rs)bc,[5]4.0[4] |
| Apparent size(V) | 1.6′×0.9′[3] |
| Notable features | Starburst galaxy[5] |
| Other designations | |
| 2MASXJ09505711+3333124,NGC3021,UGC5280,PGC28357[6] | |
NGC 3021is aspiral galaxyin the northernconstellationofLeo Minor.It is about 93 millionlight-yearsaway fromEarth,[4]and is receding with a heliocentricradial velocityof1,537±4 km/s.[4]This galaxy was discovered December 7, 1785 by Anglo-German astronomerWilliam Herschel.[7]Themorphological classificationof NGC 3021 is SA(rs)bc,[5]which indicates a spiral galaxy with no centralbar(SA), an incomplete inner ring structure (rs), and moderate to loosely woundspiral arms(bc).
Thegalaxycontains manyCepheid variable stars.Thesestarshave been used to measure the distances of galaxies. This galaxy was also used to help refine the measurement of theHubble constant.[8]
Supernova
[edit]On November 1, 1995, S. Pesci and P. Mazza in Milan, Italy reported the discovery of asupernovain the NGC 3021 galaxy. G. M. Hurst in England confirmed the finding, estimating the magnitude at 13.2. DesignatedSN 1995al,it was offset15.0″west and2.9″south of the galactic nucleus.[9]Thespectrummatched atype Ia supernovaand was found to be similar toSN 1981bnear maximum.[10]On 18 February 2023, a second supernova appeared in this galaxy: SN 2023bvj (Type II,mag. 17).[11]
References
[edit]- ^Hille, Karl (July 30, 2015)."Hubble View of a Cosmological Measuring Tape".NASA.RetrievedOctober 2,2015.
- ^abBrown, A. G. A.;et al. (Gaia collaboration) (August 2018)."GaiaData Release 2: Summary of the contents and survey properties ".Astronomy & Astrophysics.616.A1.arXiv:1804.09365.Bibcode:2018A&A...616A...1G.doi:10.1051/0004-6361/201833051.Gaia DR2 record for this sourceatVizieR.
- ^abcd"NASA/IPAC Extragalactic Database (NED)".California Institute of Technology.RetrievedOctober 2,2015.
- ^abcdefgTully, R. Brent; et al. (August 2016)."Cosmicflows-3".The Astronomical Journal.152(2): 21.arXiv:1605.01765.Bibcode:2016AJ....152...50T.doi:10.3847/0004-6256/152/2/50.S2CID250737862.50.
- ^abcAnupama, G. C. (November 1997). "Optical Spectra of Recent Supernovae of Type Ia: SN1995AL, SN1997Y, SN1997BP".Astronomical Journal.114:2054.Bibcode:1997AJ....114.2054A.doi:10.1086/118625.
- ^"NGC 3021".SIMBAD.Centre de données astronomiques de Strasbourg.Retrieved2021-12-17.
- ^Seligman, C."NGC Objects: NGC 3000 - 3049".Celestial Atlas.Retrieved2021-12-17.
- ^[email protected]."A cosmological measuring tape".spacetelescope.org.Retrieved2023-11-26.
- ^Pesci, S.; et al. (November 1995). Green, D. W. E. (ed.). "Supernova 1995al in NGC 3021".IAU Circular.6255(1): 1.Bibcode:1995IAUC.6255....1P.
- ^Wei, J. -Y.; et al. (November 1995). Green, D. W. E. (ed.). "Supernova 1995al in NGC 3021".IAU Circular.6256(1): 1.Bibcode:1995IAUC.6256....1W.
- ^"SN 2023bvj | Transient Name Server".wis-tns.org.Retrieved2023-07-06.
External links
[edit]
Media related toNGC 3021at Wikimedia Commons
