Gienah Cygni


The object was found in the following catalogues:
  1. The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version)

  2. SKY2000 - Master Star Catalog

  3. Smithsonian Astrophysical Observatory Star Catalog

  4. The Washington Visual Double Star Catalog, 1996.0


catalogues and names Gienah Cygni, e Cyg, 53 Cyg, HR 7949, HD 197989, SAO 70474, FK5: 780, WDS 20462+3358A
other names Gienah
constellation Cygnus

data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)

note (category: star names): Gienah Cygni; Gienah, also applied to HR 4662.

object is infrared source (NASA merged infrared catalogue, Schmitz et al., 1978)

position, motion, parallax:

position (J2000) RA: 20h 46min 12,7sec DEC: +33° 58' 13''
position (J1900) RA: 20h 42min 9,8sec DEC: +33° 35' 44''
proper motion (J2000) RA: 0,356 arcsec/a DEC: 0,328 arcsec/a
radial velocity -11 km/s
note: spectroscopic binaries
rotational velocity <17 km/s (uncertain) (variable)
trigonometric parallax 0,057 arcsec

magnitude

visual magnitude 2,46
(V on UBV Johnson system)

spectral / color information

spectral class K0-III
B-V-magnitude 1,03
U-B-magnitude 0,87
R-I-magnitude 0,54

double/multiple star system information

number of components of multiple star system 3
separation 54,9 arcsec
mag difference (of double or brightest multiple) 9,3
component ID AB
note (category: double and multiple data): AB optical. C, 13v at 78" CPM.

data from SKY2000 - Master Star Catalog (Myers+ 1997)

position, motion, parallax:

position (J2000) RA: 20h 46min 12,684sec DEC: +33° 58' 12,92'' ±0,06 arcsec source: 15
proper motion (J2000) RA: 0,0286 arcsec/a DEC: 0,328 arcsec/a source: 25
radial velocity -11 km/s source: 25
trigonometric parallax 0,057 ±0,006 arcsec source: 25
galactic coord. (B1950) longitude: 75,95° latitude: -5,71°
GCI unit vector (J2000) X: 0,550102 Y: -0,620623 Z: 0,558762

magnitude:

visual 2,46 (observed) source: 25
photovisual 2,6 source: 2

spectral information:

spectral class K0 source: 96
Morgan-Keenan K0III source: 25
B-magnitude 3,49 ±0,05 B-V-magnitude 1,03
U-magnitude 4,36 ±0,05 U-B-magnitude 0,87

double/multiple star system information:

source of data: 19
separation between brightest and second brightest component 0 arcsec
position angle 350 °

sources:

2 HD and HDE Catalogs
Cannon, A.J., and E.C. Pickering, Harvard Annals, Vols 91-99, 1918-24, Cambridge, Massachusetts: Harvard University; Cannon, A.J., Harvard Annals, Vol. 100, 1925-36, Cambridge, Massachusetts: Harvard University; and Cannon, A.J., and M. Walton Mayall, Harvard Annals, Vol. 112, 1949, Cambridge, Massachusetts: Harvard University
15 FK5, FK5 Extension and FK5 Supplement
Fricke, W., H. Schwan and T. Lederle, "Fifth Fundamental Catalogue (FK5), Part I. The Basic Fundamental Stars," Veroff. Astronomisches Recheninstitut, No. 32, Heidelberg, Germany, 1988, and Fricke, W., H. Schwan, and T.E. Corbin, "Fifth Fundamental Catalogue (FK5), Part II. The FK5 Extension," Veröff. Astronomisches Recheninstitut, No. 33, Heidelberg, Germany, 1991
19 WDS Catalog
Worley, C.E., and G.G. Douglass, Washington Catalog of Visual Double Stars 1996.0, United States Naval Observatory, 1996
25 Bright Star Catalogue, 5th edition
Hoffleit, D. and Warren, W.H. Jr., The Bright Star Catalogue, 5th Revised Edition, Version 2, 1994
96 SAO or HD/HDE Catalog
Reference from Value 1 or Reference from Value 2

data from Smithsonian Astrophysical Observatory Star Catalog (SAO Staff 1966; USNO, ADC 1990)

position and proper motion:

position (J1950) RA: 20h 44min 11,168sec DEC: +33° 46' 55,15'' ±0,004 arcsec
position (J2000) RA: 20h 46min 12,686sec DEC: +33° 58' 12,92''
proper motion J1950 (FK4) RA: 0,0285 arcsec/a DEC: 0,329 arcsec/a ±0,001 arcsec/a in RA
±0,001 arcsec/a in DEC
proper motion J2000 (FK5) RA: 0,0287 arcsec/a DEC: 0,328 arcsec/a
source of proper motion data Determined by source catalog

magnitude:

visual 2,6 (accuracy: 2 decimals)
source of visual magnitude data Taken from the "Henry Draper Catalogue".

spectral information:

spectral class K0
source of spectral data Taken from the Henry Draper Catalogue or no spectrum in source catalog.

catalogues

source catalogue FK4, catalogue number: 780
Durchmusterung BD+33 4018
Boss General Catalogue 28959
Henry Draper Catalogue 197989

data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)

position and proper motion:

position (J2000) RA: 20h 46,2min DEC: +33° 58'
proper motion (J2000) RA: 0,356 arcsec/a DEC: 0,328 arcsec/a

double/multiple star system information:

component year number of measures position angle angular separation magnitude of 1st component magnitude of 2nd component spectral class(es) discoverer code
Aa 1983 2 180° 0,1'' 2,46 - K0III CHR 100
1991 350° 0''
Aa-B 1852 17 339° 40,7'' 2,46 11,6 - STT
1970 269° 47,3''
Aa-C 1959 1 265° 78,1'' 2,46 13,4 - BU 676

discoverer information:

discoverer code discoverer reference
CHR 100 - -
STT Struve, O.
BU 676 Burnham, S.W. -

notes:

note Epsilon Cyg. A spectroscopic binary.