Vega

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

note (category: star names):

VEGA; Wega; Fidis; Harp Star.

position, motion, parallax:

position (J2000)	RA: 18h 36min 56.3sec	DEC: +38° 47' 1''
position (2000.73)	RA: 18h 36min 57sec	DEC: +38° 47' 4''
position (B1900)	RA: 18h 33min 33.1sec	DEC: +38° 41' 26''
proper motion (J2000)	RA: 0.202 arcsec/a	DEC: 0.286 arcsec/a
radial velocity	-14 km/s note: variable radial velocity
rotational velocity	15 km/s (uncertain) (variable)
trigonometric parallax	0.123 arcsec
galactic coordinates	longitude: 67.44°	latitude: 19.24°

note (category: radial and/or rotational velocities):

Pulsation 0.1903d.

magnitude

visual magnitude

0.03
(V on UBV Johnson system)

spectral / color information

spectral class	A0Va
B-V-magnitude	0
U-B-magnitude	-0.01
R-I-magnitude
IR-note	object is infrared source (NASA merged infrared catalogue, Schmitz et al., 1978)

note (category: spectra):

Cadmium found for first time in spectra from COPERNICUS.

note (category: colors):

Color excess E(B-V) = 0.00. Displays IR excess, however, attributed to possible proto-planetary debris.

variability information

variable star identification

Alp Lyr

note (category: variability):

Delta Sct -0.02 to +0.07V, 0.19d.

double/multiple star system information

number of components of multiple star system	5
separation	62.8 arcsec
mag difference (of double or brightest multiple)	10.4
component ID	AB

note (category: double and multiple data):

Companions in IDS optical. BD=+38d3231, 8.6v, 23' N. prec., may be CPM.

miscellaneous information

note (category: stellar radii or diameters):

Diam. = 0.00308 - 0.00324".

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

position, motion, parallax:

position (J2000)	RA: 18h 36min 56.332sec	DEC: +38° 47' 1.17''	ą0.06 arcsec	source: 15
position (2000.73)	RA: 18h 36min 57sec	DEC: +38° 47' 4''	JD: 2451810.88
proper motion (J2000)	RA: 0.0173 arcsec/a	DEC: 0.286 arcsec/a		source: 25
radial velocity	-14 km/s			source: 25
trigonometric parallax	0.123 arcsec		ą0.012 arcsec	source: 25
galactic coord. (B1950)	longitude: 67.45°	latitude: 19.24°

magnitude:

visual	0 (observed)	source: 31
photovisual	0.1	source: 2

spectral information:

spectral class	A0		source: 96
Morgan-Keenan	A0Va		source: 25
B-magnitude	0.03 ą0.05	B-V-magnitude	0
U-magnitude	0.02 ą0.05	U-B-magnitude	-0.01

variability information:

source of data: 30

variability type	10
var. amplitude	0.09
var. period	0.19

double/multiple star system information:

source of data: 19

separation between brightest and second brightest component	62.8 arcsec
magnitude difference between brightest and second brightest component	9.5
position angle	173 °

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
30	GCVS, 4th edition
Kholopov, P.N., et al., General Catalogue of Variable Stars, fourth edition, Moscow: Nauka Publishing House, 1985-88
31	CRM' (non-GCVS variable data)
Warren, W.H. Jr., Northern Hemisphere Catalog of Red Magnitudes, 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: 18h 35min 14.655sec	DEC: +38° 44' 9.68''	ą0.003 arcsec
position (2000.73)	RA: 18h 36min 57sec	DEC: +38° 46' 49''	JD: 2451810.88
position (J2000)	RA: 18h 36min 56.336sec	DEC: +38° 47' 1.18''
proper motion B1950 (FK4)	RA: 0.0171 arcsec/a	DEC: 0.285 arcsec/a	ą0.001 arcsec/a in RA ą0.001 arcsec/a in DEC
proper motion J2000 (FK5)	RA: 0.0173 arcsec/a	DEC: 0.286 arcsec/a
source of proper motion data	Determined by source catalog

magnitude:

visual	0.1 (accuracy: 2 decimals)
source of visual magnitude data	Taken from the "Henry Draper Catalogue".

spectral information:

spectral class	A0
source of spectral data	Taken from the Henry Draper Catalogue or no spectrum in source catalog.

catalogues

source catalogue	FK4, catalogue number: 699
Durchmusterung	BD+38 3238
Boss General Catalogue	25466
Henry Draper Catalogue	172167

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

position and proper motion:

position (J2000)	RA: 18h 36.9min	DEC: +38° 46'
proper motion (J2000)	RA: 0.202 arcsec/a	DEC: 0.286 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
AB	1836	43	138°	43''	0.03	9.5	A0Va	H 39
AB	1946	43	173°	62.8''	0.03	9.5	A0Va	H 39
AC	1864	4	299°	46.9''	0	11	-	STF 9
AC	1899	4	285°	54.4''	0	11	-	STF 9
AE	1905	3	39°	124.5''	0	9.5	-	STF 9
AE	1921	3	-	118.5''	0	9.5	-	STF 9
BC	1864	1	314°	89.6''	-	-	-	STF
CD	1897	1	35°	31.3''	11	-	-	STF 9

discoverer information:

discoverer code	discoverer	reference
H 39	Herschel, W.	-
STF 9	Struve, F.G.W.	-
STF	Struve, F.G.W.

notes:

note	AB: H V 39. Alpha Lyr. Proper motion of B +004 -006. Proper motion of B +002 +013. AE: Proper motion of E +007 -004. The components are optical.

data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)

position:

position (equinox 1950.0)

RA: 18h 35min 14.7sec

DEC: +38° 44' 10''

variability informations:

variability type	DSCTC	pulsating variable star
magnitute at max. brightness	-0.02
magnitute at min. brightness	0.07
photometric system	visual, photovisual or Johnson's V
period [d]	0.19

spectral information

spectral class

A0V

references

to a study	Vol. I GCVS (see Kholopov et al. 1985-1988)
to a chart/photograph	no chart is avaible, but the star is contained in the 'Bonner Durchmusterung'

miscanellous

ID in the GCVS catalogue	52/9001
constellation	Lyra
notes on existence	The star is equivalent to '0529002 bet'.
There are notes in published catalog.

variability type description

variability type

description

DSCTC

Variables of the Delta Scuti type. These are pulsating variables of spectral types A0-F5 III-V displaying light amplitudes from 0.003 to 0.9 mag in V (usually several hundredths of a magnitude) and periods from 0.01 to 0.2 days. The shapes of the light curves, periods, and amplitudes usually vary greatly. Radial as well as nonradial pulsations are observed. The variability of some
members of this type appears sporadically and sometimes completely ceases, this being a consequence of strong amplitude modulation with the lower value of the amplitude not exceeding 0.001 mag in some cases. The maximum of the surface layer expansion does not lag behind the maximum light for more than 0.1 periods. DSCT stars are representatives of the galactic disk (flat component) and are phenomenologically close to the SX Phe variables.

DSCTC
Low amplitude group of Delta Sct variables (light amplitude <0.1 mag in V). The majority of this type's representatives are stars of luminosity class V; objects of this subtype generally are representative of the Delta Sct variables in open clusters.

catalogues and names	Vega, a Lyr, alf Lyr, 3 Lyr, HR 7001, HD 172167, SAO 67174, BD +38 3238, FK5: 699, WDS 18369+3846A
other names	Wega, Fidis, Harp Star
constellation	Lyra