a Muscae


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 a Mus, alf Mus, HR 4798, HD 109668, SAO 251974, FK5: 474, WDS 12372-6908
constellation Musca

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


position, motion, parallax:

position (J2000) RA: 12h 37min 11sec DEC: -69 8' 8''
position (J1900) RA: 12h 31min 13sec DEC: -68 35' 4''
proper motion (J2000) RA: -0,048 arcsec/a DEC: -0,013 arcsec/a
radial velocity 13 km/s
note: variable radial velocity
rotational velocity 147 km/s (uncertain) (variable)

magnitude

visual magnitude 2,69
(V on UBV Johnson system)

spectral / color information

spectral class B2IV-V
B-V-magnitude -0,2
U-B-magnitude -0,83
R-I-magnitude -0,24

variability information

variable star identification Alp Mus
note (category: variability): Beta C 2.68 - 2.73V, 2.17 - 2.24p, 0.0903d.

double/multiple star system information

separation 29,6 arcsec
mag difference (of double or brightest multiple) 10,1
note Worley (1978) update of the IDS
note (category: double and multiple data): Companion B4V, optical.

miscellaneous information

note (category: group membership): Sco-Cen cluster; certain member of the Sco-Cen cluster; lower Cen group of Sco-Cen assoc.

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

position, motion, parallax:

position (J2000) RA: 12h 37min 10,958sec DEC: -69 8' 7,96'' 0,06 arcsec source: 15
proper motion (J2000) RA: -0,009 arcsec/a DEC: -0,013 arcsec/a source: 25
radial velocity 13 km/s source: 25
galactic coord. (B1950) longitude: 301,66 latitude: -6,3
GCI unit vector (J2000) X: -0,351481 Y: -0,05753 Z: -0,934426

magnitude:

visual 2,69 (observed) source: 25
photovisual 2,9 source: 2
photographic 2,8 source: 2

spectral information:

spectral class B3 source: 96
Morgan-Keenan B2IV-V source: 25
B-magnitude 2,49 0,05 B-V-magnitude -0,2
U-magnitude 1,66 0,05 U-B-magnitude -0,83

variability information:

source of data: 30
variability type 140
var. amplitude 0,05
var. period 0,09

double/multiple star system information:

source of data: 19
separation between brightest and second brightest component 29,6 arcsec
magnitude difference between brightest and second brightest component 10,3
position angle 316

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
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: 12h 34min 10,693sec DEC: -68 51' 36,83'' 0,012 arcsec
position (J2000) RA: 12h 37min 10,956sec DEC: -69 8' 7,65''
proper motion J1950 (FK4) RA: -0,0074 arcsec/a DEC: -0,016 arcsec/a 0,003 arcsec/a in RA
0,003 arcsec/a in DEC
proper motion J2000 (FK5) RA: -0,0089 arcsec/a DEC: -0,009 arcsec/a
source of proper motion data Determined by source catalog

magnitude:

visual 2,9 (accuracy: 2 decimals)
source of visual magnitude data Taken from the "Henry Draper Catalogue".

spectral information:

spectral class B3
source of spectral data Taken from the Henry Draper Catalogue or no spectrum in source catalog.

catalogues

source catalogue FK4, catalogue number: 474
Durchmusterung CP-68 1702
Boss General Catalogue 17179
Henry Draper Catalogue 109668

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

position and proper motion:

position (J2000) RA: 12h 37,2min DEC: -69 8'
proper motion (J2000) RA: -0,048 arcsec/a DEC: -0,013 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
- 1932 2 316 29,6'' 2,69 13 B2IV-V DON 541

discoverer information:

discoverer code discoverer reference
DON 541 Donner, H.F. -

notes:

note Alpha Mus. Variable.

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

position:

position (J1950) RA: 12h 34min 10,7sec DEC: -68 51' 37''

variability informations:

variability type BCEP pulsating variable star
magnitute at max. brightness 2,68
magnitute at min. brightness 2,73
photometric system visual, photovisual or Johnson's V
period [d] 0,0903

spectral information

spectral class B2IV-V

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 'Cape Photographic Durchmusterung'

miscanellous

ID in the GCVS catalogue 56/9001
constellation Musca
notes on existence The star is equivalent to '0569005 eps'.
There are notes in published catalog.

variability type description

variability type description
BCEP Variables of the Beta Cephei type (Beta Cep, Beta CMa), which are pulsating O8-B6 I-V stars with periods of light and radial-velocity variations in the range of 0.1 - 0.6 days and light amplitudes from 0.01 to 0.3 mag in V. The light curves are similar in shape to average radial-velocity curves but lag in phase by a quarter of the period, so that maximum brightness corresponds to
maximum contraction, i.e., to minimum stellar radius. The majority of these stars probably show radial pulsations, but some (V649 Per) display nonradial pulsations; multiperiodicity is characteristic of many of these stars.