NGC 4194 | |
---|---|
Observation data (J2000 epoch) | |
Constellation | Ursa Major |
Right ascension | 12 14 09.64 |
Declination | +54° 31′ 34.60″ |
Redshift | 0.008433 |
Heliocentric radial velocity | 2,511±12 km/s |
Distance | 128 Mly (39.1 Mpc) |
Apparent magnitude (V) | 13.30 |
Apparent magnitude (B) | 13.79 |
Characteristics | |
Type | Imeger |
Apparent size (V) | 0.14′ × 0.13′ |
Notable features | Interacting, starburst |
Other designations | |
Medusa galaxy merger, NGC 4194, Arp 160, UGC 7241, Mrk 201, PGC 39068 |
NGC 4194, the Medusa merger, is a galaxy merger in the constellation Ursa Major about 128 million light-years (39.1 Mpc) away. It was discovered on April 2, 1791 by German-British astronomer William Herschel. Due to its disturbed appearance, it is object 160 in Halton Arp's 1966 Atlas of Peculiar Galaxies.
The morphological classification of NGC 4194 is Imeger, indicating an irregular form. This galaxy consists of a brighter central region spanning an angular size 9″ across, with an accompanying system of loops and arcs. Additional material is thinly spread out to a radius of 75″ from the central region. There is a tidal tail and regions undergoing high levels of star formation, making this a starburst galaxy. It is a source for strong infrared and radio emission. These features indicate NGC 4194 is a late-stage galaxy merger. A region of extreme star formation 500 ly (150 pc) across exists in the center of the Eye of Medusa, the central gas-rich region.
Within 1.2 kpc (3.9 kly) of the dynamic center of NGC 4194, star formation is occurring at a rate of 8 M☉·yr. The star forming regions in this volume range from 5 to 9 million years in age, with the youngest occurring in areas of the highest star formation rate. As of 2014, no galactic nucleus has been detected based on radio emissions, nor have the respective nuclei of the merger galaxies. However, X-ray emission from a black hole in the tidal tail was detected by Chandra in 2009.
References
- ^ Samsonyan, Anahit; et al. (September 2016). "Neon and [C II] 158 μm Emission Line Profiles in Dusty Starbursts and Active Galactic Nuclei". The Astrophysical Journal Supplement Series. 226 (1). id. 11. arXiv:1608.02277. Bibcode:2016ApJS..226...11S. doi:10.3847/0067-0049/226/1/11.
- ^ 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. S2CID 119253507.
- Falco, Emilio E.; et al. (April 1999). "The Updated Zwicky Catalog (UZC)". Publications of the Astronomical Society of the Pacific. 111 (758): 438. arXiv:astro-ph/9904265. Bibcode:1999PASP..111..438F. doi:10.1086/316343. S2CID 14298026.
- ^ Lianou, S.; et al. (November 2019). "Dust properties and star formation of approximately a thousand local galaxies". Astronomy & Astrophysics. 631: 19. arXiv:1906.02712. Bibcode:2019A&A...631A..38L. doi:10.1051/0004-6361/201834553. S2CID 174801441. A38.
- ^ Véron-Cetty, M.-P.; Véron, P. (2010). "A catalogue of quasars and active nuclei: 13th edition". Astronomy & Astrophysics. 518 (A10): A10. Bibcode:2010A&A...518A..10V. doi:10.1051/0004-6361/201014188.
- "Results for NGC 4194". NASA/IPAC Extragalactic Database. Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. January 12, 2007. Retrieved 2024-03-24.
- ^ "NGC 4194". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2024-03-24.
- Seligman, Courtney. "NGC Objects: NGC 4150 - 4199". Celestial Atlas. Retrieved 2024-04-01.
- Demoulin, Marie-Helene (April 1969). "The Peculiar Galaxy NGC 4194". Astrophysical Journal. 156: 325. Bibcode:1969ApJ...156..325D. doi:10.1086/149967.
- Weistrop, D.; et al. (March 2004). "Looking Closely at Medusa: Star-forming Knots at the Center of NGC 4194". The Astronomical Journal. 127 (3): 1360–1370. Bibcode:2004AJ....127.1360W. doi:10.1086/382092.
- Hancock, M.; et al. (December 2003). "A Spectroscopic Study of the Star-Forming Properties of the Center of NGC 4194". The Astronomical Journal. 131 (1): 1394. Bibcode:2003AAS...20311515H. doi:10.1086/497969.
- Joseph, R. D.; Wright, G. S. (May 1985). "Recent star formation in interacting galaxies - II. Super starbursts in merging galaxies". Monthly Notices of the Royal Astronomical Society. 214 (2): 87–95. Bibcode:1985MNRAS.214...87J. doi:10.1093/mnras/214.2.87.
- "Unknown extreme star formation discovered". Space Daily. 17 June 2015. Retrieved 2024-03-24.
- Weistrop, D.; et al. (April 2012). "Characteristics of Star-forming Regions in the Advanced Minor-merger, Luminous Infrared Galaxy NGC 4194". The Astronomical Journal. 143 (4). id. 98. Bibcode:2012AJ....143...98W. doi:10.1088/0004-6256/143/4/98.
- Beck, Sara C.; et al. (May 2014). "Ionized Gas Kinematics at High Resolution. IV. Star Formation and a Rotating Core in the Medusa (NGC 4194)". The Astrophysical Journal. 787 (1). id. 85. arXiv:1404.1562. Bibcode:2014ApJ...787...85B. doi:10.1088/0004-637X/787/1/85.
- "NGC 4194: A Black Hole in Medusa's Hair". Chandra Photo Album. March 11, 2009. Retrieved 2024-04-01.
Further reading
- König, S.; et al. (July 2018). "Major impact from a minor merger. The extraordinary hot molecular gas flow in the Eye of the NGC 4194 Medusa galaxy". Astronomy & Astrophysics. 615. id. A122. arXiv:1712.04030. Bibcode:2018A&A...615A.122K. doi:10.1051/0004-6361/201732436.
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: CS1 maint: multiple names: authors list (link) - Aalto, S.; et al. (November 2010). "CO 1-0 imaging of the Medusa merger, NGC 4194. Large scale variations in molecular cloud properties". Astronomy and Astrophysics. 522. id.A59. arXiv:1008.2095. Bibcode:2010A&A...522A..59A. doi:10.1051/0004-6361/200913511.
- Kaaret, Philip; Alonso-Herrero, Almudena (August 2008). "X-Ray Sources in the Star-Forming Galaxies NGC 4194 and NGC 7541". The Astrophysical Journal. 682 (2): 1020–1028. arXiv:0805.0683. Bibcode:2008ApJ...682.1020K. doi:10.1086/589764.
External links
- NGC 4194 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images