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

  5. Combined General Catalogue of Variable Stars (Vol. I-III)

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

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

note (category: star names): VEGA; Wega; Fidis; Harp Star.

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

position, motion, parallax:

position (J2000) RA: 18h 36min 56,3sec DEC: +38 47' 1''
position (J1900) 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
note (category: radial and/or rotational velocities): Pulsation 0.1903d.


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 -0,03
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'' 0,06 arcsec source: 15
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 0,012 arcsec source: 25
galactic coord. (B1950) longitude: 67,45 latitude: 19,24
GCI unit vector (J2000) X: 0,125096 Y: -0,769413 Z: 0,626381


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 0,05 B-V-magnitude 0
U-magnitude 0,02 0,05 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


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 (J1950) RA: 18h 35min 14,655sec DEC: +38 44' 9,68'' 0,003 arcsec
position (J2000) RA: 18h 36min 56,336sec DEC: +38 47' 1,18''
proper motion J1950 (FK4) RA: 0,0171 arcsec/a DEC: 0,285 arcsec/a 0,001 arcsec/a in RA
0,001 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


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.


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
1946 173 62,8''
AC 1864 4 299 46,9'' 0 11 - STF 9
1899 285 54,4''
AE 1905 3 39 124,5'' 0 9,5 - STF 9
1921 - 118,5''
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.


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 (J1950) 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


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'


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.

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.