4C 58.17
| 4C 58.17 | |
|---|---|
SDSS image of 4C 58.17 | |
| Observation data (J2000.0 epoch) | |
| Constellation | Ursa Major |
| Right ascension | 08h 54m 41.99s[1] |
| Declination | +57° 57′ 29.93″[1] |
| Redshift | 1.317368[1] |
| Heliocentric radial velocity | 394,937 km/s[1] |
| Distance | 9.036 Gly |
| Apparent magnitude (V) | 18.18 |
| Apparent magnitude (B) | 18.56 |
| Characteristics | |
| Type | LPQ FSRQ[1] |
| Size | ~215,000 ly (65.8 kpc) (estimated)[1] |
| Notable features | superluminal quasar |
| Other designations | |
| SDSS J085442.00+575729.9, LEDA 2821457, NVSS J085441+575729, VLSS J0854.7+5757, 6C B085050.2+580854, S4 0850+58, VIPS 163, RX J0854.6+5757, 2CXO J085442.0+575730[1] | |
4C 58.17 also known as 0850+581, is a quasar located in the northern constellation of Ursa Major. The redshift of the object is (z) 1.317 estimating a light-travel time distance of 9 billion light years away from Earth[1] and was first discovered as an astronomical radio source by astronomers in 1981.[2] It is a flat-spectrum radio quasar and a superluminal source.[3][4]
Description
4C 58.17 has a compact triple radio structure.[5][4] When imaged with Very Long Baseline Interferometry (VLBI), it is shown to have a core-jet morphology that is typical of powerful observed quasars, being mainly dominated by strong nuclear radio emission with a bright radio core and a secondary component present at a position angle of 170° with its distance being 4.5 milliarcseconds away.[6] New VLBI and Very Large Array (VLA) observations showed there is a northern component on mas-scale, several secondary components and a weak resolved feature present in the quasar. This northern component is estimated to hold 85% of the flux density.[7]
A study published in 1986 found 4C 58.17 has superluminal motion in its core. Based on studies, the core of the source is found to be expanding at a speed of 5.3 ± 0.8 per hour with its components separation increasing while the position angle of the components decreases per year.[4] A new component has emerged close to the core position, described as elongated along the position angle of 174 ± 4°.[7] The core itself is variable at slight frequencies with a fairly steep spectrum of between 15 and 5 GHz.[4] It is suggested the core might also be shifting by one milliarcsecond between 2 and 8 GHz.[8]
The jet travelling from the core region towards a southeast hotspot on arcsecond scales in 4C 58.17 is described as both curved and knotty, and also displaying a cork-screw behavior.[4][9] When imaged by the Very Long Baseline Array (VLBA), it takes the form of a two-sided jet moving at relativistic speeds with a counter-jet feature displaying diffused radio emission. There is a noted switch in its orientation, indicating it might be interacting with the surround interstellar medium. The Faraday rotation polarization located downstream from the core by 2 milliarcseconds shows a negative unit of -1612 ± 102 rad/m2, before rising to 270 ± 70 rad/m2 upon reaching 3.5 milliarcseconds.[10] A supermassive black hole mass of 8.49 Mʘ has been estimated for this quasar.[11]
References
- ^ a b c d e f g h "NED Search results for 4C 58.17". NASA/IPAC Extragalactic Database. Retrieved 2025-09-13.
- ^ Pearson, T. J.; Readhead, A. C. S. (August 1981). "The milli-arcsecond structure of a complete sample of radio sources. I. VLBI maps of seven sources". The Astrophysical Journal. 248: 61–81. Bibcode:1981ApJ...248...61P. doi:10.1086/159130. ISSN 0004-637X.
- ^ Zensus, J. A.; Porcas, R. W.; Pauliny-Toth, I. I. K. (April 1984). "VLBI study of 57 flat spectrum radio sources at 5 GHz". Astronomy and Astrophysics. 133: 27–30. Bibcode:1984A&A...133...27Z. ISSN 0004-6361.
- ^ a b c d e Barthel, P. D.; Pearson, T. J.; Readhead, A. C. S.; Canzian, B. J. (November 1986). "0850+581: Another Superluminal Radio Source". The Astrophysical Journal. 310: L7. Bibcode:1986ApJ...310L...7B. doi:10.1086/184771. ISSN 0004-637X.
- ^ Pearson, T. J.; Readhead, A. C. S. (May 1988). "The Milliarcsecond Structure of a Complete Sample of Radio Sources. II. First-Epoch Maps at 5 GHz". The Astrophysical Journal. 328: 114. Bibcode:1988ApJ...328..114P. doi:10.1086/166274. ISSN 0004-637X.
- ^ Hooimeyer, J. R. A.; Barthel, P. D.; Schilizzi, R. T.; Miley, G. K. (July 1992). "The radio structure of extended quasars. I. A VLBI survey of the nuclear emission". Astronomy and Astrophysics. 261: 18–24. Bibcode:1992A&A...261...18H. ISSN 0004-6361.
- ^ a b Hooimeyer, J. R. A.; Schilizzi, R. T.; Miley, G. K.; Barthel, P. D. (July 1992). "The radio structure of extended quasars. II. The radio emission on pc- and kpc-scales". Astronomy and Astrophysics. 261: 25–40. Bibcode:1992A&A...261...25H. ISSN 0004-6361.
- ^ Kovalev, Y. Y.; Lobanov, A. P.; Pushkarev, A. B. (2008-10-13). "Physics of the central region in the quasar 0850+581". Memorie della Societa Astronomica Italiana. 79: 1153. arXiv:0810.2240. Bibcode:2008MmSAI..79.1153K.
- ^ Rusk, R. E.; Seaquist, E. R. (September 1986). "The Arcsecond Brightness and Polarization Structure of 0850+581". Bulletin of the American Astronomical Society. 18: 994. Bibcode:1986BAAS...18..994R.
- ^ Kravchenko, E. V.; Kovalev, Y. Y. (2017-12-02). "Multi-Frequency VLBA Polarimetry and the Twin-Jet Quasar 0850+581". Galaxies. 5 (4): 92. arXiv:1712.00572. Bibcode:2017Galax...5...92K. doi:10.3390/galaxies5040092.
- ^ Liu, Yi; Jiang, Dong Rong; Gu, Min Feng (2005-10-08). "The Jet Power, Radio Loudness, and Black Hole Mass in Radio-loud Active Galactic Nuclei". The Astrophysical Journal. 637 (2): 669–681. arXiv:astro-ph/0510241. doi:10.1086/498639.