catalogues and names

The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version)

SKY2000 - Master Star Catalog

Smithsonian Astrophysical Observatory Star Catalog

The Washington Visual Double Star Catalog, 1996.0

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

catalogues and names

catalogues and names	a Mus, alf Mus, HR 4798, HD 109668, SAO 251974, CP -68 1702, 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 (2000.72)	RA: 12h 37min 14sec	DEC: -69° 8' 22''
position (B1900)	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)
galactic coordinates	longitude: 301.66°	latitude: -6.3°

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

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
position (2000.72)	RA: 12h 37min 14sec	DEC: -69° 8' 22''	JD: 2451809.17
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°

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 (B1950)	RA: 12h 34min 10.693sec	DEC: -68° 51' 36.83''	±0.012 arcsec
position (2000.72)	RA: 12h 37min 14sec	DEC: -69° 8' 21''	JD: 2451809.17
position (J2000)	RA: 12h 37min 10.956sec	DEC: -69° 8' 7.65''
proper motion B1950 (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 (equinox 1950.0)

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.