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	o Her, omi Her, 103 Her, HR 6779, HD 166014, SAO 85750, BD +28 2925, FK5: 681, WDS 18075+2846
constellation	Hercules

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

position, motion, parallax:

position (J2000)	RA: 18h 7min 32.6sec	DEC: +28° 45' 45''
position (B1900)	RA: 18h 3min 38.4sec	DEC: +28° 44' 55''
proper motion (J2000)	RA: 0.001 arcsec/a	DEC: 0.009 arcsec/a
radial velocity	-30 km/s note: spectroscopic binaries
rotational velocity	134 km/s (uncertain) (variable)
trigonometric parallax	0.005 arcsec
galactic coordinates	longitude: 55.19°	latitude: 21.59°

magnitude

visual magnitude

3.83 (V on UBV Johnson system)

spectral / color information

spectral class	B9.5V
B-V-magnitude	-0.03
U-B-magnitude	-0.07
R-I-magnitude

note (category: spectra):

H alpha emission.

variability information

variable star identification

Omi Her

note (category: variability):

Gamma Cas 3.81 - 3.9B, 4.1 - 4.2p.

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

position, motion, parallax:

position (J2000)	RA: 18h 7min 32.555sec	DEC: +28° 45' 45.01''	±0.06 arcsec	source: 15
proper motion (J2000)	RA: 0.0001 arcsec/a	DEC: 0.009 arcsec/a		source: 25
radial velocity	-30 km/s			source: 25
trigonometric parallax	0.005 arcsec		-	source: 25
galactic coord. (B1950)	longitude: 55.19°	latitude: 21.59°

magnitude:

visual	3.83 (observed)	source: 25
photovisual	3.8	source: 2

spectral information:

spectral class	A0		source: 96
Morgan-Keenan	B9.5V		source: 25
B-magnitude	3.8 ±0.05	B-V-magnitude	-0.03
U-magnitude	3.73 ±0.05	U-B-magnitude	-0.07

variability information:

source of data: 30

variability type	264
var. amplitude	0.07

double/multiple star system information:

source of data: 19

separation between brightest and second brightest component	0.1 arcsec
position angle	107 °

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: 18h 5min 35.418sec	DEC: +28° 45' 15.79''	±0.004 arcsec
position (J2000)	RA: 18h 7min 32.554sec	DEC: +28° 45' 45.04''
proper motion B1950 (FK4)	RA: -0.0001 arcsec/a	DEC: 0.01 arcsec/a	±0.001 arcsec/a in RA ±0.001 arcsec/a in DEC
proper motion J2000 (FK5)	RA: 0.0001 arcsec/a	DEC: 0.01 arcsec/a
source of proper motion data	Determined by source catalog

magnitude:

visual	3.8 (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: 681
Durchmusterung	BD+28 2925
Boss General Catalogue	24711
Henry Draper Catalogue	166014

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

position and proper motion:

position (J2000)	RA: 18h 7.5min	DEC: +28° 46'
proper motion (J2000)	RA: 0.001 arcsec/a	DEC: 0.01 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
-	1981	1	107°	0.1''	3.83	-	B9.5V	STA

discoverer information:

discoverer code	discoverer	reference
STA	Starikova, G.A.

notes:

note	Omicron Her. A spectroscopic and interferometric binary.

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

position:

position (equinox 1950.0)

RA: 18h 5min 35.4sec

DEC: +28° 45' 16''

variability informations:

variability type	GCAS	eruptive variable star
magnitute at max. brightness	3.8
magnitute amplitude	0.07
photometric system

spectral information

spectral class

B9Ve

references

to a chart/photograph

no chart is avaible, but the star is contained in the 'Bonner Durchmusterung'

miscanellous

ID in the GCVS catalogue	40/9015
constellation	Hercules
notes on existence	The star is equivalent to '0409024 ome'.
There are notes in published catalog.

variability type description

variability type	description
GCAS	Eruptive irregular variables of the Gamma Cas type. These are rapidly rotating B III-IVe stars with mass outflow from their equatorial zones. The formation of equatorial rings or disks is often accompanied by temporary fading. Light amplitudes may reach 1.5 mag in V.