Messier 60

Messier 60 or M60, also known as NGC 4649, is an elliptical galaxy approximately 57[4] million light-years away in the equatorial constellation of Virgo. Together with NGC 4647, it forms a pair known as Arp 116.[7] Messier 60 and the nearby elliptical galaxy Messier 59 were both discovered by Johann Gottfried Koehler in April 1779 during observations of a comet in the same part of the sky.[8] Charles Messier added both to his catalogue about three days after Koehler's discovery.[8]

Messier 60
M60 by Hubble Space Telescope; 3.33′ view
Observation data (J2000 epoch)
ConstellationVirgo[1]
Right ascension 12h 43m 40.008s[2]
Declination+11° 33′ 09.40″[2]
Redshift0.003726[3]
Helio radial velocity1,108 km/s[4]
Distance56.7 Mly (17.38 Mpc)[4]
Group or clusterVirgo Cluster
Apparent magnitude (V)9.8[3]
Characteristics
TypeE1.5 or S0[5]
Apparent size (V)7′.4 × 6′.0[3]
Other designations
M60, NGC 4649, PGC 42831, UGC 7898.[6]

Characteristics

This is an elliptical galaxy of type E1/2 (E1.5), although some sources class it as S0 – a lenticular galaxy. An E2 class indicates a flattening of 20%, which has a nearly round appearance. The isophotes of the galaxy are boxy in shape, rather than simple ellipses. The mass-to-light ratio is a near constant 9.5 in the V (visual) band of the UBV system.[5] The galaxy has an effective radius of 128″ (about 10 kpc[5]), with an estimated mass of ~1012 M☉ within three times that radii, of which nearly half is dark matter.[9] The mass estimated from X-ray emission is (1.0±0.1)×1012 M☉ within 5 effective radii.[10]

Supermassive black hole

At the center of M60 is a supermassive black hole (SMBH) of 4.5±1.0 billion solar masses, one of the largest ever found.[11] It is currently inactive. X-ray emission from the galaxy shows a cavity created by jets emitted by the hole during past active periods, which correspond to weak radio lobes. The power needed to generate these features is in the range (6–7)×1041 erg·s−1.[12]

Supernovae

In 2004, supernova SN 2004W was observed in Messier 60.[13] It was a type 1a supernova located 51.6″ west and 78.7″ south of the nucleus.[14]

Environment

M60 is the third-brightest giant elliptical galaxy of the Virgo cluster of galaxies, and is the dominant member of a subcluster of four galaxies, the M60 group, which is the closest-known isolated compact group of galaxies.[15] It has several satellite galaxies, one of them being the ultracompact dwarf galaxy M60-UCD1, discovered in 2013.[16] The motion of M60 through the intercluster medium is resulting in ram-pressure stripping of gas from the galaxy's outer halo, beyond a radius of 12 kpc.[10]

NGC 4647 appears approximately 2′.5 from Messier 60; the optical disks of the two galaxies overlap. Although this overlap suggests that the galaxies are interacting, photographic images of the two galaxies do not reveal any evidence for gravitational interactions between the two galaxies as would be suggested if the two galaxies were physically close to each other.[17] This suggests that the galaxies are at different distances and are only weakly interacting if at all.[17] However, studies with the Hubble Space Telescope show indications that a tidal interaction may have just begun.[7]

Recession speed and distance estimations

Messier 60 was the fastest-moving galaxy included in Edwin Hubble's landmark 1929 paper concerning the relationship between recession speed and distance.[18] He used a value of 1090 km/s for the recession speed, quite close to the more recent value of about 1110 km/s (based on a redshift of 0.003726). But he estimated the distance of Messier 60, as well as of the other three nebulas of the Virgo Cluster which he included (Messier 85, 49, and 87), to be only two million parsecs, rather than the accepted value today of around 16 million parsecs. These errors in distance led him to propose a "Hubble constant" of 500 km/s/Mpc, whereas the present estimate is around 70 km/s/Mpc.

  • Arp 116 is composed of a giant elliptical galaxy known as Messier 60, and a much smaller spiral galaxy, NGC 4647.
  • M60 and the region around it, including the ultra-compact dwarf galaxy M60-UCD1 near the bottom.
  • M60 and NGC 4647

See also

References
  1. Sinnott, R. W., ed. (1988). The Complete New General Catalogue and Index Catalogue of Nebulae and Star Clusters by J. L. E. Dreyer. Sky Publishing Corporation /Cambridge University Press. ISBN 978-0-933346-51-2.
  2. Skrutskie, M. F.; et al. (February 2006), "The Two Micron All Sky Survey (2MASS)", The Astronomical Journal, 131 (2): 1163–1183, Bibcode:2006AJ....131.1163S, doi:10.1086/498708.
  3. "NASA/IPAC Extragalactic Database". Results for Messier 60. Retrieved 2006-12-13.
  4. 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.
  5. De Bruyne, V.; et al. (January 2001), "Toward an Alternative Way of Looking at Elliptical Galaxies: Case Studies for NGC 4649 and NGC 7097", The Astrophysical Journal, 546 (2): 903–915, Bibcode:2001ApJ...546..903D, doi:10.1086/318275.
  6. "M 60". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2006-11-16.
  7. "Odd Galaxy Couple On Space Voyage". Science Daily. September 6, 2012. Retrieved 2012-11-11.
  8. Jones, K. G. (1991). Messier's Nebulae and Star Clusters (2nd ed.). Cambridge University Press. ISBN 978-0-521-37079-0.
  9. Teodorescu, A. M.; et al. (July 2011), "Planetary Nebulae in the Elliptical Galaxy NGC 4649 (M 60): Kinematics and Distance Redetermination", The Astrophysical Journal, 736 (1): 16, arXiv:1105.1209, Bibcode:2011ApJ...736...65T, doi:10.1088/0004-637X/736/1/65, 65.
  10. Paggi, Alessandro; et al. (July 2017), "Constraining the Physical State of the Hot Gas Halos in NGC 4649 and NGC 5846", The Astrophysical Journal, 844 (1): 30, arXiv:1706.02303, Bibcode:2017ApJ...844....5P, doi:10.3847/1538-4357/aa7897, 5.
  11. Shen, Juntai; Gebhardt, Karl (2010). "The Supermassive Black Hole and Dark Matter Halo of NGC 4649 (M60)". The Astrophysical Journal. 711 (1): 484–494. arXiv:0910.4168. Bibcode:2010ApJ...711..484S. doi:10.1088/0004-637X/711/1/484.
  12. Shurkin, K.; et al. (January 2008), "Active galactic nuclei-induced cavities in NGC 1399 and NGC 4649", Monthly Notices of the Royal Astronomical Society, 383 (3): 923–930, arXiv:0710.5704, Bibcode:2008MNRAS.383..923S, doi:10.1111/j.1365-2966.2007.12651.x.
  13. "Supernova 2004W in M60". 2005.
  14. Moore, M.; et al. (February 2004), Green, D. W. E. (ed.), "Supernovae 2004T, 2004U, and 2004W", IAU Circular, 8286: 2, Bibcode:2004IAUC.8286....2M.
  15. Mamon, G. A. (July 1, 2008). "The nature of the nearest compact group of galaxies from precise distance measurements". Astronomy & Astrophysics. 486 (1): 113–117. arXiv:0803.3181. Bibcode:2008A&A...486..113M. doi:10.1051/0004-6361:200809827. ISSN 0004-6361.
  16. Sandoval, Michael A.; et al. (July 23, 2015). "Hiding in Plain Sight: Record-breaking Compact Stellar Systems in the Sloan Digital Sky Survey". The Astrophysical Journal. 808 (1): L32. arXiv:1506.08828. Bibcode:2015ApJ...808L..32S. doi:10.1088/2041-8205/808/1/L32.
  17. Sandage, A.; Bedke, J. (1994). Carnegie Atlas of Galaxies. Carnegie Institution of Washington. ISBN 978-0-87279-667-6.
  18. Edwin Hubble (1929). "A relation between distance and radial velocity among extra-galactic nebulae". PNAS. 15 (3): 168–173. Bibcode:1929PNAS...15..168H. doi:10.1073/pnas.15.3.168. PMC 522427. PMID 16577160.

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.