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	e Cen, eps Cen, HR 5132, HD 118716, SAO 241047, CP -52 6655, FK5: 504, WDS 13399-5328
constellation	Centaurus

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

position, motion, parallax:

position (J2000)	RA: 13h 39min 53.2sec	DEC: -53° 27' 59''
position (2000.72)	RA: 13h 39min 56sec	DEC: -53° 28' 12''
position (B1900)	RA: 13h 33min 32.9sec	DEC: -52° 57' 28''
proper motion (J2000)	RA: -0.028 arcsec/a	DEC: -0.016 arcsec/a
radial velocity	3 km/s
rotational velocity	159 km/s (uncertain) (variable)
galactic coordinates	longitude: 310.19°	latitude: 8.72°

magnitude

visual magnitude

2.3 (V on UBV Johnson system)

spectral / color information

spectral class	B1III
B-V-magnitude	-0.22
U-B-magnitude	-0.92
R-I-magnitude

variability information

variable star identification

Eps Cen

note (category: variability):

Beta C 2.30 - 2.31V, 0.169608, 0.17696 or 0.2150d. Multi-periodic.

double/multiple star system information

separation	36.9 arcsec
mag difference (of double or brightest multiple)	8.4
note	Worley (1978) update of the IDS

note (category: double and multiple data):

Companion B1p, optical.

miscellaneous information

note (category: group membership):

Sco-Cen assoc.; probable member of Sco-Cen cluster.

note (category: stellar radii or diameters):

Diam. = 0.00047 - 0.00048".

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

position, motion, parallax:

position (J2000)	RA: 13h 39min 53.246sec	DEC: -53° 27' 58.99''	±0.06 arcsec	source: 15
position (2000.72)	RA: 13h 39min 56sec	DEC: -53° 28' 12''	JD: 2451809.17
proper motion (J2000)	RA: -0.0032 arcsec/a	DEC: -0.016 arcsec/a		source: 25
radial velocity	3 km/s			source: 25
galactic coord. (B1950)	longitude: 310.2°	latitude: 8.72°

magnitude:

visual	2.3 (observed)	source: 25
photovisual	2.6	source: 2
photographic	2.3	source: 2

spectral information:

spectral class	B1		source: 96
Morgan-Keenan	B1III		source: 25
B-magnitude	2.08 ±0.05	B-V-magnitude	-0.22
U-magnitude	1.16 ±0.05	U-B-magnitude	-0.92

variability information:

source of data: 30

variability type	140
var. amplitude	0.02
var. period	0.17
var. epoch	2441041 30. March 1971, 12:00:00 UT
next max light	2451809.31 21. September 2000, 19:26:24 UT

double/multiple star system information:

source of data: 19

separation between brightest and second brightest component	36.9 arcsec
magnitude difference between brightest and second brightest component	10.7
position angle	158 °

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: 13h 36min 42.322sec	DEC: -53° 12' 46.33''	±0.01 arcsec
position (2000.72)	RA: 13h 39min 56sec	DEC: -53° 28' 10''	JD: 2451809.17
position (J2000)	RA: 13h 39min 53.282sec	DEC: -53° 27' 58.72''
proper motion B1950 (FK4)	RA: -0.0025 arcsec/a	DEC: -0.017 arcsec/a	±0.002 arcsec/a in RA ±0.002 arcsec/a in DEC
proper motion J2000 (FK5)	RA: -0.0028 arcsec/a	DEC: -0.013 arcsec/a
source of proper motion data	Determined by source catalog

magnitude:

visual	2.6 (accuracy: 2 decimals)
source of visual magnitude data	Taken from the "Henry Draper Catalogue".

spectral information:

spectral class	B1
source of spectral data	Taken from the Henry Draper Catalogue or no spectrum in source catalog.

catalogues

source catalogue	FK4, catalogue number: 504
Durchmusterung	CP-52 6655
Boss General Catalogue	18458
Henry Draper Catalogue	118716

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

position and proper motion:

position (J2000)	RA: 13h 39.9min	DEC: -53° 28'
proper motion (J2000)	RA: -0.028 arcsec/a	DEC: -0.017 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
-	1948	2	158°	36''	2.3	13	B1III	RST5376
	1967		-	36.9''

discoverer information:

discoverer code	discoverer	reference
RST5376	Rossiter, R.A.	-

notes:

note	Epsilon Cen.

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

position:

position (equinox 1950.0)

RA: 13h 36min 42.3sec

DEC: -53° 12' 46''

variability informations:

variability type	BCEP	pulsating variable star
magnitute at max. brightness	2.29
magnitute at min. brightness	2.31
photometric system	visual, photovisual or Johnson's V
epoch for maximum light [JD]	2441040.965 30. March 1971, 11:09:36 UT
period [d]	0.169608
next maximum light [JD]	2451809.207312 21. September 2000, 16:58:32 UT

spectral information

spectral class

B1III

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 'Cordoba Durchmusterung'

miscanellous

ID in the GCVS catalogue	19/9005
constellation	Centaurus
notes on existence	The star is equivalent to '0199007 eta'.
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.