theta Cygni

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

position, motion, parallax:

magnitude

visual magnitude

4.48
(V on UBV Johnson system)

spectral / color information

spectral class	F4V
B-V-magnitude	0.38
U-B-magnitude	-0.03
R-I-magnitude
IR-note	object is infrared source (uncertain identification)

double/multiple star system information

number of components of multiple star system	3
separation	48.4 arcsec
mag difference (of double or brightest multiple)	6.9
component ID	AC

note (category: double and multiple data):

AB CPM. B, 13v at 3". C, optical.

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

position, motion, parallax:

magnitude:

visual	4.48 (observed)	source: 25
photovisual	4.6	source: 2

spectral information:

double/multiple star system information:

source of data: 19

separation between brightest and second brightest component	3.2 arcsec
magnitude difference between brightest and second brightest component	8.4
position angle	60 °

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 (B1950)	RA: 19h 35min 5.974sec	DEC: +50° 6' 16.12''	±0.003 arcsec
position (J2000)	RA: 19h 36min 26.463sec	DEC: +50° 13' 15.54''
proper motion B1950 (FK4)	RA: -0.0025 arcsec/a	DEC: 0.256 arcsec/a	±0.001 arcsec/a in RA ±0.001 arcsec/a in DEC
proper motion J2000 (FK5)	RA: -0.0022 arcsec/a	DEC: 0.255 arcsec/a
source of proper motion data	Determined by source catalog

magnitude:

visual	4.6 (accuracy: 2 decimals)
source of visual magnitude data	Taken from the "Henry Draper Catalogue".

spectral information:

spectral class	F5
source of spectral data	Taken from the Henry Draper Catalogue or no spectrum in source catalog.

catalogues

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

position and proper motion:

position (J2000)	RA: 19h 36.4min	DEC: +50° 13'
proper motion (J2000)	RA: -0.017 arcsec/a	DEC: 0.257 arcsec/a

double/multiple star system information:

discoverer information:

notes:

note	Theta Cyg. Young and Farnsworth (Astron. J. 35, 180; 1924) suggested that a faint companion 2' west was physical. Bidelman (Pub. Astron. Soc. Pacific 92, 345; 1980) confirms that the spectral type, M2/3 is consis- tant with this suggestion.

catalogues and names	q Cyg, 13 Cyg, HR 7469, HD 185395, SAO 31815, BD +49 3062, FK5: 738, WDS 19364+5013A
constellation	Cygnus