Astronomy:Messier 84

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Short description: Galaxy in the constellation Virgo
Messier 84
Messier 84 nucleus by HST
Galaxy Messier 84 in Virgo, imaged by the Hubble Space Telescope
Observation data (J2000 epoch)
ConstellationVirgo
Right ascension 12h 25m 03.74333s[1]
Declination+12° 53′ 13.1393″[1]
Redshift1,060±6 km/s[2]
Helio radial velocity999[3] km/s
Distance54.9 Mly (16.83 Mpc)[3]
Apparent magnitude (V)9.1[4]
Absolute magnitude (V)−22.41±0.10[5]
Characteristics
TypeE1[5]
Apparent size (V)6.5 × 5.6[2]
Half-light radius (apparent)72.5±6[5]
Other designations
M84, NGC 4374, PGC 40455, UGC 7494, VCC 763[6]

Messier 84 or M84, also known as NGC 4374, is a giant elliptical or lenticular galaxy in the constellation Virgo. Charles Messier discovered the object in 1781[lower-alpha 1] in a systematic search for "nebulous objects" in the night sky.[7] It is the 84th object in the Messier Catalogue and in the heavily populated core of the Virgo Cluster of galaxies, part of the local supercluster.[8]

This galaxy has morphological classification E1, denoting it has flattening of about 10%. The extinction-corrected total luminosity in the visual band is about 7.64×1010 solar luminosity. The central mass-to-light ratio is 6.5, which, to a limit, steadily increases away from the core. The visible galaxy is surrounded by a massive dark matter halo.[5]

Radio observations and Hubble Space Telescope images of M84 have revealed two jets of matter shooting out from its center as well as a disk of rapidly rotating gas and stars indicating the presence of a 1.5 ×109 M[9] supermassive black hole. It also has a few young stars and star clusters, indicating star formation at a very low rate.[10] The number of globular clusters is 1,775±150, which is much lower than expected for an elliptical galaxy.[11]

Viewed from Earth its half-light radius, relative angular size of its 50% peak of lit zone of the sky, is 72.5″, thus just over an arcminute.

Two supernovae have been observed in M84: SN 1957B[12] and SN 1991bg.[13] Seen between these dates, it may have bore a third, SN 1980I – which may have been in either neighboring galaxy NGC 4387 or M86.[14] This high rate of supernovae is rare for elliptical galaxies, which may indicate there is a population of stars of intermediate age in M84.[11]

Location of M84

See also

References and footnotes

  1. 1.0 1.1 Lambert, S. B.; Gontier, A.-M. (January 2009). "On radio source selection to define a stable celestial frame". Astronomy and Astrophysics 493 (1): 317–323. doi:10.1051/0004-6361:200810582. Bibcode2009A&A...493..317L. 
  2. 2.0 2.1 "NASA/IPAC Extragalactic Database". Results for NGC 4374. http://ned.ipac.caltech.edu/cgi-bin/objsearch?objname=m84&extend=no&hconst=73&omegam=0.27&omegav=0.73&corr_z=1&out_csys=Equatorial&out_equinox=J2000.0&obj_sort=RA+or+Longitude&of=pre_text&zv_breaker=30000.0&list_limit=5&img_stamp=YES. 
  3. 3.0 3.1 Tully, R. Brent et al. (August 2016). "Cosmicflows-3". The Astronomical Journal 152 (2): 21. doi:10.3847/0004-6256/152/2/50. 50. Bibcode2016AJ....152...50T. 
  4. "Messier 84". https://messier.seds.org/m/m084.html. 
  5. 5.0 5.1 5.2 5.3 Napolitano, N. R. et al. (March 2011). "The PN.S Elliptical Galaxy Survey: a standard ΛCDM halo around NGC 4374?". Monthly Notices of the Royal Astronomical Society 411 (3): 2035–2053. doi:10.1111/j.1365-2966.2010.17833.x. Bibcode2011MNRAS.411.2035N. 
  6. "M 84". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=M+84. 
  7. Jones, K. G. (1991). Messier's Nebulae and Star Clusters (2nd ed.). Cambridge: Cambridge University Press. ISBN 978-0-521-37079-0. 
  8. Finoguenov, A.; Jones, C. (2002). "Chandra Observation of Low-Mass X-Ray Binaries in the Elliptical Galaxy M84". Astrophysical Journal 574 (2): 754–761. doi:10.1086/340997. Bibcode2002ApJ...574..754F. 
  9. Bower, G.A. et al. (1998). "Kinematics of the Nuclear Ionized Gas in the Radio Galaxy M84 (NGC 4374)". Astrophysical Journal 492 (1): 111–114. doi:10.1086/311109. Bibcode1998ApJ...492L.111B. 
  10. Ford, Alyson; Bregman, J. N. (2012). "Detection of Ongoing, Low-Level Star Formation in Nearby Ellipticals". American Astronomical Society 219: 102.03. Bibcode2012AAS...21910203F. 
  11. 11.0 11.1 Gómez, M.; Richtler, T. (February 2004). "The globular cluster system of NGC 4374". Astronomy and Astrophysics 415 (2): 499–508. doi:10.1051/0004-6361:20034610. Bibcode2004A&A...415..499G. 
  12. Götz, W. (1958). "Supernova in NGC 4374 (= M 84)". Astronomische Nachrichten 284 (3): 141–142. doi:10.1002/asna.19572840308. Bibcode1958AN....284..141G. 
  13. Kosai, H. et al. (1958). "Supernova 1991bg in NGC 4374". IAU Circular 5400: 1. Bibcode1991IAUC.5400....1K. 
  14. Smith, H. A. (1981). "The spectrum of the intergalactic supernova 1980I". Astronomical Journal 86: 998–1002. doi:10.1086/112975. Bibcode1981AJ.....86..998S. 
  1. on 18 March

External links

Coordinates: Sky map 12h 25m 03.7s, +12° 53′ 13″