Messier 84

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Messier 84
Messier 84 nucleus by HST
M84. Credit:NOAO.
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)10.1[2]
Absolute magnitude (V)−22.41±0.10[4]
Characteristics
TypeE1[4]
Apparent size (V)6′.5 × 5′.6[2]
Half-light radius (apparent)72.5±6[4]
Other designations
M84, NGC 4374, PGC 40455, UGC 7494, VCC 763[5]
See also: Galaxy, List of galaxies

Messier 84 or M84, also known as NGC 4374, is an elliptical or lenticular galaxy in the constellation Virgo. Charles Messier discovered Messier 84 on 18 March 1781 in a systematic search for "nebulous objects" in the night sky.[6] The object is the 84th in the Messier Catalogue. M84 is situated in the heavily populated inner core of the Virgo Cluster of galaxies.[7]

This is a giant elliptical galaxy with a morphological classification of E1, indicating a flattening of 10%. The half-light radius is 72.5″ and the extinction-corrected total luminosity in the visual band is 7.64×1010 L. The central mass-to-light ratio is 6.5, which steadily increases away from the core. The visible galaxy is surrounded by a massive dark matter halo.[4]

Radio observations and Hubble Space Telescope images of M84 have revealed two jets of matter shooting out from the galaxy's center as well as a disk of rapidly rotating gas and stars indicating the presence of a 1.5 ×109 M[8] supermassive black hole. It also has a few young stars and star clusters, indicating star formation at a very low rate.[9] The number of globular clusters is 1,775±150, which is much lower than expected for an elliptical galaxy.[10]

Two supernovae have been observed in M84: SN 1957[11] and SN 1991bg.[12] Possibly, a third, SN 1980I is part of M84 or, alternatively, one of its neighboring galaxies, NGC 4387 and M86.[13] This high rate of supernova events is rare for elliptical galaxies, which may indicate there is a population of stars of intermediate age in M84.[10]

References[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 c "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. 50.
  4. ^ 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.
  5. ^ "M 84". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2009-12-17.
  6. ^ Jones, K. G. (1991). Messier's Nebulae and Star Clusters (2nd ed.). Cambridge: Cambridge University Press. ISBN 978-0-521-37079-0.
  7. ^ 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.
  8. ^ 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.
  9. ^ 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.
  10. ^ 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.
  11. ^ Götz, W. (1958). "Supernova in NGC 4374 (= M 84)". Astronomische Nachrichten. 284 (3): 141–142. Bibcode:1958AN....284..141G. doi:10.1002/asna.19572840308.
  12. ^ Kosai, H.; et al. (1958). "Supernova 1991bg in NGC 4374". IAU Circular. 5400: 1. Bibcode:1991IAUC.5400....1K.
  13. ^ Smith, H. A. (1981). "The spectrum of the intergalactic supernova 1980I". Astronomical Journal. 86: 998–1002. Bibcode:1981AJ.....86..998S. doi:10.1086/112975.

External links[edit]

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