56 Cygni
{{short description|Star in the constellation Cygnus}}
{{Starbox begin
| name = 56 Cygni
}}
{{Starbox observe
| epoch = J2000
| constell = Cygnus
| dec = {{DEC|+44|03|33.4862}}
}}
{{Starbox character
| type =
| u-b =
| variable =
}}
{{Starbox astrometry
| radial_v = {{Val|−21.5|3.5}}
| parallax = 24.1034
| p_error = 0.1344
}}
{{Starbox detail
| mass = 1.72
| radius =
| temperature = {{Val|8124|276|fmt=commas}}
| gravity = {{Val|4.28|0.14}}
| metal_fe =
| age_myr = 394
}}
{{Starbox catalog
| names = {{odlist | F=56 Cyg | BD=+43°3739 | FK5=3666 | HD=198639 | HIP=102843 | HR=7984 | SAO=50121 | WDS=J20501+4404 }}
}}
{{Starbox reference
| Simbad=56+Cyg
}}
{{Starbox end}}
56 Cygni is a single star in the northern constellation of Cygnus, located 135 light years from Earth. It is visible to the naked eye as a white-hued star with an apparent visual magnitude of 5.06. The star is moving closer to the Earth with a heliocentric radial velocity of −21.5. It has a relatively high proper motion, traversing the celestial sphere at an angular rate of {{Val|0.181|ul=arcsecond}}/yr. According to Eggen (1998), this is a member of the Hyades Supercluster.
This is an A-type main-sequence star with a stellar classification of A6 V. Cowley et al. (1969) classified it as a Delta Delphini star, which is a type of suspected Am star. The star is around 394 million years old with a projected rotational velocity of 73 km/s. It has 1.72 times the mass of the Sun and is radiating 13 times the Sun's luminosity from its photosphere at an effective temperature of 8,124 K.
56 Cygni has a visual companion: a magnitude 11.9 star at an angular separation of {{Val|55.4|u=arcsecond}} along a position angle of 48°, as of 2015.
References
{{reflist|refs=
{{cite simbad | title=56 Cyg | access-date=2019-01-16 }}
{{Cite Gaia DR2|2067050940754838656}}
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{{citation | display-authors=1
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| title=The Age Range of Hyades Stars
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| journal=The Astronomical Journal
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| doi=10.1086/300413 | bibcode=1998AJ....116..284E | doi-access=free }}
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| volume=32 | issue=11 | pages=759–771 | year=2006
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| postscript=. }}
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| title=The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog
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}}
{{Stars of Cygnus}}
Category:A-type main-sequence stars
Category:Cygnus (constellation)