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[a] 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]

Messier 84
Messier 84 nucleus by HST
Galaxy Messier 84 in Virgo, imaged by the Hubble Space Telescope
Observation data (J2000 epoch)
ConstellationVirgo
Right ascension12h 25m 03.74333s[1]
Declination+12° 53′ 13.1393″[1]
Redshift1,060±6 km/s[2]
Heliocentric 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]

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 L. 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 edit

References and footnotes edit

  1. ^ a b 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. Bibcode:2009A&A...493..317L. doi:10.1051/0004-6361:200810582.
  2. ^ a b "NASA/IPAC Extragalactic Database". Results for NGC 4374. Retrieved 2006-11-14.
  3. ^ a b Tully, 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. S2CID 250737862. 50.
  4. ^ "Messier 84". SEDS Messier Catalog. Retrieved 30 April 2022.
  5. ^ a b c d 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. arXiv:1010.1533. Bibcode:2011MNRAS.411.2035N. doi:10.1111/j.1365-2966.2010.17833.x. S2CID 52221902.
  6. ^ "M 84". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2009-12-17.
  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. arXiv:astro-ph/0204046. Bibcode:2002ApJ...574..754F. doi:10.1086/340997. S2CID 17551432.
  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. arXiv:astro-ph/9710264. Bibcode:1998ApJ...492L.111B. doi:10.1086/311109. S2CID 119456112.
  10. ^ Ford, Alyson; Bregman, J. N. (2012). "Detection of Ongoing, Low-Level Star Formation in Nearby Ellipticals". American Astronomical Society. 219: 102.03. Bibcode:2012AAS...21910203F.
  11. ^ a b Gómez, M.; Richtler, T. (February 2004). "The globular cluster system of NGC 4374". Astronomy and Astrophysics. 415 (2): 499–508. arXiv:1703.00313. Bibcode:2004A&A...415..499G. doi:10.1051/0004-6361:20034610.
  12. ^ Götz, W. (1958). "Supernova in NGC 4374 (= M 84)". Astronomische Nachrichten. 284 (3): 141–142. Bibcode:1958AN....284..141G. doi:10.1002/asna.19572840308.
  13. ^ Kosai, H.; et al. (1958). "Supernova 1991bg in NGC 4374". IAU Circular. 5400: 1. Bibcode:1991IAUC.5400....1K.
  14. ^ Smith, H. A. (1981). "The spectrum of the intergalactic supernova 1980I". Astronomical Journal. 86: 998–1002. Bibcode:1981AJ.....86..998S. doi:10.1086/112975.
  1. ^ on 18 March

External links edit