57 Cygni

{{Starbox begin

| name = 57 Cygni

}}

{{Starbox observe

| epoch = J2000

| constell = Cygnus

| ra = {{RA|20|53|14.75503}}

| dec = {{DEC|+44|23|14.1408}}

| appmag_v = 4.80

}}

{{Starbox character

| type =

| class = B5 V

| b-v = {{Val|−0.134|0.006}}

| u-b =

| variable =

}}

{{Starbox astrometry

| radial_v = {{Val|−21.1|2.8}}

| prop_mo_ra = +11.94

| prop_mo_dec = −2.08

| parallax = 6.21

| p_error = 0.22

| parallax_footnote =

| absmag_v = −1.23

}}

{{Starbox orbit

| reference =

| period_unitless = 2.8548 days

| axis =

| axis_unitless =

| eccentricity = {{Val|0.139|0.014}}

| inclination = ≈ 48

| node =

| periastron = 2441571.275 JD

| periarg = 159.6

| periarg_primary =

| k1 = 111.9

| k2 = 126.0

}}

{{Starbox detail

| source =

| component1 = 57 Cyg A

| mass = {{Val|5.54|0.55}}

| radius = {{Val|3.3|0.4}}

| luminosity =

| temperature = 17,190

| gravity =

| metal_fe =

| rotational_velocity = 40

| age_myr =

| component2 = 57 Cyg B

| mass2 = {{Val|4.92|0.49}}

| radius2 = {{Val|2.9|0.4}}

| rotational_velocity2 = 30

}}

{{Starbox catalog

| names = {{odlist | F=57 Cyg | BD=+43°3755 | FK5= | HD=199081 | HIP=103089 | HR=8001 | SAO=50180 }}

}}

{{Starbox reference

| Simbad=57+Cyg

}}

57 Cygni is a close binary star system in the constellation Cygnus, located about 530 light years from Earth. It is visible to the naked eye as a blue-white hued star with a baseline apparent visual magnitude of 4.80. The pair have a magnitude difference of 0.34. This system is moving closer to the Earth with a heliocentric radial velocity of −21 km/s.

This is a double-lined spectroscopic binary with an orbital period of 2.85 days and an eccentricity of 0.15. They show a steady change in their longitude of periastron, showing an apsidal period of {{Val|203|4|u=years}}. The system does not form an eclipsing binary, having the orbital inclination of around 48°. Both components are B-type main-sequence stars with a stellar classification of B5 V.

References

{{reflist|refs=

{{citation

| last1=Zorec | first1=J. | last2=Cidale | first2=L.

| last3=Arias | first3=M. L. | last4=Frémat | first4=Y.

| last5=Muratore | first5=M. F. | last6=Torres | first6=A. F.

| last7=Martayan | first7=C. | last8=Martayan | first8=C.

| title=Fundamental parameters of B supergiants from the BCD system. I. Calibration of the (λ₁, D) parameters into T_eff

| display-authors=1 | journal=Astronomy and Astrophysics

| volume=501 | issue=1 | pages=297–320 | date=July 2009

| doi=10.1051/0004-6361/200811147 | bibcode=2009A&A...501..297Z

| arxiv=0903.5134 | s2cid=14969137 | postscript=. }}

{{citation | postscript=.

| last=Lesh | first=Janet Rountree

| title=The Kinematics of the Gould Belt: an Expanding Group?

| journal=Astrophysical Journal Supplement

| volume=17 | page=371 | date=December 1968

| doi=10.1086/190179 | bibcode=1968ApJS...17..371L | doi-access=free}}

{{citation

| title=XHIP: An extended hipparcos compilation

| last1=Anderson | first1=E. | last2=Francis | first2=Ch.

| journal=Astronomy Letters

| volume=38 | issue=5 | pages=331 | year=2012

| bibcode=2012AstL...38..331A | doi=10.1134/S1063773712050015

| arxiv=1108.4971 | s2cid=119257644 | postscript=. }}

{{citation

| title=Photometry of V 1794 Cygni between 1975 and 1995

| display-authors=1 | last1=Jetsu | first1=L.

| last2=Tuominen | first2=I. | last3=Bopp | first3=B. W.

| last4=Ezhkova | first4=O. V. | last5=Grankin | first5=K. N.

| last6=Hackman | first6=T. | last7=Heckert | first7=P. A.

| last8=Ibragimov | first8=M. A. | last9=Kondratiev | first9=V. B.

| last10=Mel'Nikov | first10=S. Yu. | last11=Oja | first11=T.

| last12=Nations | first12=H. L. | last13=Shevchenko | first13=V. S.

| journal=Astronomy and Astrophysics Supplement | postscript=.

| volume=139 | pages=513–523 | date=November 1999

| issue=3 | doi=10.1051/aas:1999397 | bibcode=1999A&AS..139..513J | doi-access=free }}

{{citation

| title=Validation of the new Hipparcos reduction

| last1=van Leeuwen | first1=F.

| journal=Astronomy and Astrophysics

| volume=474 | issue=2 | pages=653–664 | date=2007

| arxiv=0708.1752 | bibcode=2007A&A...474..653V

| doi=10.1051/0004-6361:20078357 | s2cid=18759600 | postscript=. }}

{{citation

| title=Testing gravitational theories using eccentric eclipsing detached binaries

| last1=De Laurentis | first1=M. | last2=De Rosa | first2=R.

| last3=Garufi | first3=F. | last4=Milano | first4=L.

| display-authors=1 | journal=Monthly Notices of the Royal Astronomical Society

| doi=10.1111/j.1365-2966.2012.21410.x | doi-access=free | bibcode=2012MNRAS.424.2371D | arxiv=1207.5410 | s2cid=119109320 }}

{{citation

| title=The binary system 57 Cygni - apsidal motion and effects of spectral line blending

| last1=Hilditch | first1=R. W. | postscript=.

| journal=Monthly Notices of the Royal Astronomical Society

| volume=164 | pages=101–110 | year=1973

| issue=2 | doi= 10.1093/mnras/164.2.101| bibcode=1973MNRAS.164..101H | doi-access=free}}

{{citation

| title=On the spectroscopic binary 57 Cygni

| last1=Tapia | first1=M. | last2=Smith | first2=R. C.

| journal=Monthly Notices of the Royal Astronomical Society

| doi=10.1093/mnras/189.3.551 | bibcode=1979MNRAS.189..551T | doi-access=free }}

{{citation

| display-authors=1 | last1=Abt | first1=Helmut A.

| last2=Levato | first2=Hugo | last3=Grosso | first3=Monica

| title=Rotational Velocities of B Stars | journal=The Astrophysical Journal

| volume=573 | issue=1 | pages=359–365 | date=July 2002

| doi=10.1086/340590 | bibcode=2002ApJ...573..359A | doi-access=free }}

}}

Category:B-type main-sequence stars

Category:Spectroscopic binaries

Category:Cygnus (constellation)

Category:Durchmusterung objects

Category:Suspected variables