56 Cygni is a single[8] star in the northern constellation of Cygnus, located 135[1] light years from Earth. It is visible to the naked eye as a white-hued star with an apparent visual magnitude of 5.06.[2] The star is moving closer to the Earth with a heliocentric radial velocity of −21.5.[2] It has a relatively high proper motion, traversing the celestial sphere at an angular rate of 0.181″/yr.[9] According to Eggen (1998), this is a member of the Hyades Supercluster.[10]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cygnus |
| Right ascension | 20h 50m 04.93129s[1] |
| Declination | +44° 03′ 33.4862″[1] |
| Apparent magnitude (V) | 5.06[2] |
| Characteristics | |
| Spectral type | A6 V[3] |
| B−V color index | 0.198±0.002[4] |
| Astrometry | |
| Radial velocity (Rv) | −21.5±3.5[2] km/s |
| Proper motion (μ) | RA: +123.450[1] mas/yr Dec.: +132.420[1] mas/yr |
| Parallax (π) | 24.1034 ± 0.1344 mas[1] |
| Distance | 135.3 ± 0.8 ly (41.5 ± 0.2 pc) |
| Absolute magnitude (MV) | 2.00[4] |
| Details[5] | |
| Mass | 1.72 M☉ |
| Luminosity | 13.19[4] L☉ |
| Surface gravity (log g) | 4.28±0.14 cgs |
| Temperature | 8,124±276 K |
| Rotational velocity (v sin i) | 73[6] km/s |
| Age | 394 Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an A-type main-sequence star with a stellar classification of A6 V.[3] Cowley et al. (1969) classified it as a Delta Delphini star,[11] which is a type of suspected Am star. The star is around 394[5] million years old with a projected rotational velocity of 73 km/s.[6] It has 1.72[5] times the mass of the Sun and is radiating 13[4] times the Sun's luminosity from its photosphere at an effective temperature of 8,124 K.[5]
56 Cygni has a visual companion: a magnitude 11.9 star at an angular separation of 55.4″ along a position angle of 48°, as of 2015.[12]
References
edit- ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c d Gontcharov, G. A. (2006), "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system", Astronomy Letters, 32 (11): 759–771, arXiv:1606.08053, Bibcode:2006AstL...32..759G, doi:10.1134/S1063773706110065, S2CID 119231169.
- ^ a b Abt, Helmut A.; Morrell, Nidia I. (July 1995), "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars", Astrophysical Journal Supplement, 99: 135, Bibcode:1995ApJS...99..135A, doi:10.1086/192182
- ^ a b c d Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
- ^ a b c d David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal, 804 (2): 146, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146, S2CID 33401607.
- ^ a b Royer, F.; et al. (October 2002), "Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin i", Astronomy and Astrophysics, 393: 897–911, arXiv:astro-ph/0205255, Bibcode:2002A&A...393..897R, doi:10.1051/0004-6361:20020943, S2CID 14070763.
- ^ "56 Cyg". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-01-16.
- ^ Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
- ^ Lépine, Sébastien; Shara, Michael M. (March 2005), "A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)", The Astronomical Journal, 129 (3): 1483–1522, arXiv:astro-ph/0412070, Bibcode:2005AJ....129.1483L, doi:10.1086/427854, S2CID 2603568.
- ^ Eggen, Olin J. (July 1998), "The Age Range of Hyades Stars", The Astronomical Journal, 116 (1): 284–292, Bibcode:1998AJ....116..284E, doi:10.1086/300413.
- ^ Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819.
- ^ Mason, Brian D.; et al. (December 2001), "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog", The Astronomical Journal, 122 (6): 3466–3471, Bibcode:2001AJ....122.3466M, doi:10.1086/323920.