beta 2 Cygni

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

position, motion, parallax:

position (J2000)	RA: 19h 30min 45,3sec	DEC: +27° 57' 55''
position (2001,17)	RA: 19h 30min 48sec	DEC: +27° 58' 4''
position (B1900)	RA: 19h 26min 43,4sec	DEC: +27° 45' 18''
proper motion (J2000)	RA: -0,009 arcsec/a	DEC: 0 arcsec/a
radial velocity	-18 km/s note: variable radial velocity
rotational velocity	250 km/s (uncertain) (variable)
trigonometric parallax	0,017 arcsec
galactic coordinates	longitude: 62,12°	latitude: 4,57°

note (category: dynamical parallaxes):

0.009".

magnitude

visual magnitude

5,11
(V on UBV Johnson system)

spectral / color information

double/multiple star system information

number of components of multiple star system	3
separation	34,7 arcsec
mag difference (of double or brightest multiple)	2
component ID	AB

note (category: double and multiple data):

See HR 7417. Unresolved by speckle interferometry 1981.47, sep. <0.03".

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

position, motion, parallax:

magnitude:

spectral information:

double/multiple star system information:

source of data: 25

separation between brightest and second brightest component	34,4 arcsec
magnitude difference between brightest and second brightest component	2

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
16	PPM North and PPM South Catalogs and PPM Supplement
Roser, S., and U. Bastian, "Catalogue of Positions and Proper Motions," A&AS, Vol. 74, p. 449, 1988, and Bastian, U., et al., "Catalogue of Positions and Proper Motions - South," 1993
17	ACRS
Corbin, T.E., and S.E. Urban, Astrographic Catalog Reference Stars, United States Naval Observatory, 1991
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 28min 44,302sec	DEC: +27° 51' 32,69''	ą0,022 arcsec
position (2001,17)	RA: 19h 30min 48sec	DEC: +27° 58' 4''	JD: 2451973,10
position (J2000)	RA: 19h 30min 45,338sec	DEC: +27° 57' 55,18''
proper motion B1950 (FK4)	RA: -0,0008 arcsec/a	DEC: 0,002 arcsec/a	ą0,003 arcsec/a in RA ą0,004 arcsec/a in DEC
proper motion J2000 (FK5)	RA: -0,0007 arcsec/a	DEC: 0 arcsec/a
source of proper motion data	Determined by source catalog

magnitude:

visual	5,4 (accuracy: 2 decimals)
source of visual magnitude data	Taken from Harvard or San Luis photometry.

spectral information:

spectral class	B9
source of spectral data	Taken from the Henry Draper Catalogue or no spectrum in source catalog.

remarks for duplicity and variability

Double star in Aitken's Double Star Catalogue (Aitken 1932)

catalogues

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

position and proper motion:

position (J2000)	RA: 19h 30,7min	DEC: +27° 58'
proper motion (J2000)	RA: 0,002 arcsec/a	DEC: -0,002 arcsec/a

double/multiple star system information:

discoverer information:

notes:

note	Aa: Beta (1) Cyg. Resolved in 1976 by speckle interferometry and has also been seen visually. Aa-B: B is BD+27@3411. Proper motion of B +003 -004, spectrum B8V.

catalogues and names	b²Cyg, 6 Cyg, HR 7418, HD 183914, SAO 87302, BD +27 3411, WDS 19307+2758B
constellation	Cygnus