Black Eye Galaxy

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Messier 64[1]
Blackeyegalaxy.jpg
The core of the Black Eye Galaxy (M64) as taken with Hubble's Wide Field Planetary Camera 2
Observation data (J2000 epoch)
ConstellationComa Berenices[2]
Right ascension 12h 56m 43.696s[3]
Declination+21° 40′ 57.57″[3]
Redshift0.001361±0.000013[4]
Helio radial velocity410[5]
Galactocentric velocity400±4[6]
Distance (comoving)17.3 Mly (5.30 Mpc)[5]
Group or clusterCVn I[7]
Apparent magnitude (V)8.52[8]
Apparent magnitude (B)9.36[8]
Characteristics
Type(R)SA(rs)ab,[4] HIISy2
Apparent size (V)10.71 × 5.128 arcminute[9]
Other designations
Evil Eye Galaxy, M64, NGC 4826, PGC 44182, UGC 8062[9]
See also: Galaxy, List of galaxies

The Black Eye Galaxy (also called Evil Eye Galaxy and designated Messier 64, M64, or NGC 4826) is a relatively isolated[7] spiral galaxy located 17 million light years away in the northern constellation of Coma Berenices. It was discovered by Edward Pigott in March 1779, and independently by Johann Elert Bode in April of the same year, as well as by Charles Messier in 1780. A dark band of absorbing dust in front of the galaxy's bright nucleus gave rise to its nicknames of the "Black Eye" or "Evil Eye" galaxy. M64 is well known among amateur astronomers because of its appearance in small telescopes.

This galaxy is inclined 60° to the line-of-sight and has a position angle of 112°.[7] At the distance of this galaxy, it has a linear scale of 65 ly (20 pc) per arcsecond.[7] The morphological classification of NGC 4826 in the De Vaucouleurs system is (R)SA(rs)ab,[4] where the '(R)' indicates an outer ring-like structure, 'SA' denotes a non-barred spiral, '(rs)' means a transitional inner ring/spiral structure, and 'ab' says the spiral arms are fairly tightly wound.[10] Ann et al. (2015) gave it a class of SABa,[11] suggesting a weakly-barred spiral galaxy with tightly wound arms.

M64 is a type 2 Seyfert galaxy[12] with an HII/LINER nucleus. The central region is a weak source of radio emission.[7] A soft X-ray source has been detected at the nucleus, which is most likely coming from the circumnuclear region rather than directly from an active galactic nucleus.[13] There is an inner disk of molecular gas that is truncated at a radius of 2,300 ly (700 pc). At present, the non-rotational motions of this disk do not significantly feed the core, but the disk does produce a vigorous rate of star formation. There is also evidence of a recent large inflow of mass.[14]

The interstellar medium of Messier 64 consists of two counter-rotating disks that are approximately equal in mass.[15] The inner disk contains the prominent dust lanes of the galaxy. The stellar population of the galaxy exhibits no measurable counter-rotation.[16] Possible formation scenarios include a merger with a gas-rich satellite galaxy in a retrograde orbit, or the continued accretion of gas clouds from the intergalactic medium.[15][16] It has a diameter of 54,000 light-years (17 kpc).[17]

References[edit]

  1. ^ Tonry, J. L.; et al. (2001), "The SBF Survey of Galaxy Distances. IV. SBF Magnitudes, Colors, and Distances", Astrophysical Journal, 546 (2): 681–693, arXiv:astro-ph/0011223, Bibcode:2001ApJ...546..681T, doi:10.1086/318301.
  2. ^ Dreyer, J. L. E. (1988), Sinnott, R. W. (ed.), The Complete New General Catalogue and Index Catalogue of Nebulae and Star Clusters, Sky Publishing Corporation/Cambridge University Press, ISBN 978-0-933346-51-2.
  3. ^ a b 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.
  4. ^ a b c de Vaucouleurs, G.; et al. (1991), Third reference catalogue of bright galaxies, 9, New York: Springer-Verlag.
  5. ^ 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.
  6. ^ "NASA/IPAC Extragalactic Database", Results for NGC 4826, retrieved 2018-12-13.
  7. ^ a b c d e Israel, F. P. (January 2009), "CI and CO in nearby galaxy centers. The bright galaxies NGC 1068 (M 77), NGC 2146, NGC 3079, NGC 4826 (M 64), and NGC 7469", Astronomy and Astrophysics, 493 (2): 525–538, arXiv:0811.4058, Bibcode:2009A&A...493..525I, doi:10.1051/0004-6361:200810655.
  8. ^ a b Gil de Paz, Armando; et al. (2007), "The GALEX Ultraviolet Atlas of Nearby Galaxies", Astrophysical Journal Supplement Series, 173 (2): 185–255, arXiv:astro-ph/0606440, Bibcode:2007ApJS..173..185G, doi:10.1086/516636.
  9. ^ a b "M 64". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-12-13.
  10. ^ de Vaucouleurs, Gérard (April 1963), "Revised Classification of 1500 Bright Galaxies", Astrophysical Journal Supplement, 8: 31, Bibcode:1963ApJS....8...31D, doi:10.1086/190084.
  11. ^ Ann, H. B.; et al. (2015), "A Catalog of Visually Classified Galaxies in the Local (z ∼ 0.01) Universe", The Astrophysical Journal Supplement Series, 217 (2): 27–49, arXiv:1502.03545, Bibcode:2015ApJS..217...27A, doi:10.1088/0067-0049/217/2/27.
  12. ^ Malkan, Matthew A.; et al. (September 2017), "Emission Line Properties of Seyfert Galaxies in the 12 μm Sample", The Astrophysical Journal, 846 (2): 26, arXiv:1708.08563, Bibcode:2017ApJ...846..102M, doi:10.3847/1538-4357/aa8302, 102.
  13. ^ Grier, C. J.; Mathur, S.; Ghosh, H.; Ferrarese, L. (April 2011), "Discovery of Nuclear X-ray Sources in Sings Galaxies", The Astrophysical Journal, 731 (1): 13, arXiv:1011.4295, Bibcode:2011ApJ...731...60G, doi:10.1088/0004-637X/731/1/60, 60.
  14. ^ García-Burillo, S.; et al. (August 2003), "Molecular Gas in NUclei of GAlaxies (NUGA). I. The counter-rotating LINER NGC 4826", Astronomy and Astrophysics, 407 (2): 485–502, arXiv:astro-ph/0306140, Bibcode:2003A&A...407..485G, doi:10.1051/0004-6361:20030866.
  15. ^ a b Brawn, R.; Walterbos, R. A. M.; Kennicutt, Robert C., Jr. (1992). "Counter-rotating gaseous disks in the "Evil Eye" galaxy NGC4826". Nature. 360 (6403): 442. Bibcode:1992Natur.360..442B. doi:10.1038/360442a0.
  16. ^ a b Rix, Hans-Walter R.; Kennicutt, Robert C., Jr.; Walterbos, Rene A. M. (1995). "Placid stars and excited gas in NGC 4826". Astrophysical Journal. 438: 155. Bibcode:1995ApJ...438..155R. doi:10.1086/175061.
  17. ^ From trigonometry: diameter = distance × sin( diameter_angle) = 17.3 Myr × sin(10.71′) = 53,896 ly.

External links[edit]

Coordinates: Sky map 12h 56m 43.7s, +21° 40′ 58″