V0819 Herculis

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

position, motion, parallax:

position (J2000)	RA: 17h 21min 43.6sec	DEC: +39° 58' 28''
position (B1900)	RA: 17h 18min 26.6sec	DEC: +40° 4' 22''
proper motion (J2000)	RA: 0.009 arcsec/a	DEC: -0.063 arcsec/a
radial velocity	3 km/s note: spectroscopic binaries, double lined spectra
rotational velocity	12 km/s (uncertain) (variable)
trigonometric parallax	0.021 arcsec
galactic coordinates	longitude: 64.69°	latitude: 33.58°

magnitude

visual magnitude

5.51
(V on UBV Johnson system)

spectral / color information

spectral class	F9Vn:
B-V-magnitude	0.68
U-B-magnitude	0.21

note (category: spectra):

Also classified F7V?+G5IV. Weak H alpha emission.

variability information

variable star identification

V819 Her

note (category: variability):

E, amp. 0.085V, 2.2299d. Also long period var. outside eclipse, amp. 0.04V, 83.2d; probably the rotation period of the G5IV component.

double/multiple star system information

separation	0 arcsec
note	doublicity discoverd by speckle interferometry

note (category: double and multiple data):

Recognized as triple system by speckle interferometry: single star G5IV and close pair of which the brighter component is F7V eclipsing, sep. 0.045".

note (category: spectroscopic binaries):

5.53y.

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

position, motion, parallax:

position (J2000)	RA: 17h 21min 43.645sec	DEC: +39° 58' 28.75''	ą0.2 arcsec	source: 52
proper motion (J2000)	RA: 0.0012 arcsec/a	DEC: -0.065 arcsec/a		source: 25
radial velocity	3 km/s			source: 25
trigonometric parallax	0.021 arcsec		ą0.002 arcsec	source: 25
galactic coord. (B1950)	longitude: 64.69°	latitude: 33.58°

magnitude:

visual	5.51 (observed)	source: 25
photovisual	5.7	source: 2
photographic	6.2	source: 16

spectral information:

spectral class	F8		source: 96
Morgan-Keenan	G5IV+F2V		source: 25
B-magnitude	6.19 ą0.05	B-V-magnitude	0.68
U-magnitude	6.4 ą0.05	U-B-magnitude	0.21

variability information:

source of data: 27

variability type	10
var. amplitude	0.1

double/multiple star system information:

source of data: 19

separation between brightest and second brightest component	0.1 arcsec
position angle	330 °

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
16	PPM North and PPM South Catalogs and PPM Supplement
Roser, S., and U. Bastian, "Catalogue of Positions and Proper Motions," A&AS, Vol. 74, p. 449, 1988, and Bastian, U., et al., "Catalogue of Positions and Proper Motions - South," 1993
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
27	Catalog of Red Magnitudes (CRM)
Warren, W.H. Jr., Northern Hemisphere Catalog of Red Magnitudes, 1994
52	PPMN-HP subset
PPMN Star Catalogue (Reference 16) High-Precision Subset (Code H)
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: 17h 20min 5.031sec	DEC: +40° 1' 21.48''	ą0.022 arcsec
position (J2000)	RA: 17h 21min 43.609sec	DEC: +39° 58' 28.27''
proper motion B1950 (FK4)	RA: 0.0003 arcsec/a	DEC: -0.065 arcsec/a	ą0.004 arcsec/a in RA ą0.003 arcsec/a in DEC
proper motion J2000 (FK5)	RA: 0.0008 arcsec/a	DEC: -0.064 arcsec/a
source of proper motion data	Determined by source catalog

magnitude:

visual	5.7 (accuracy: 2 decimals)
source of visual magnitude data	Taken from Harvard or San Luis photometry.

spectral information:

spectral class	F8
source of spectral data	Taken from the Henry Draper Catalogue or no spectrum in source catalog.

catalogues

source catalogue	GC, catalogue number: 23487
Durchmusterung	BD+40 3136
Boss General Catalogue	23487
Henry Draper Catalogue	157482

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

position and proper motion:

position (J2000)	RA: 17h 21.7min	DEC: +39° 58'
proper motion (J2000)	RA: 0.014 arcsec/a	DEC: -0.054 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
-	1980	15	92°	0''	5.5	-	F9V	MCA 47
-	1993	15	330°	0.1''	5.5	-	F9V	MCA 47

discoverer information:

discoverer code	discoverer	reference
MCA 47	McAlister, H.A.	-

notes:

note	P = 5.54yr., a = 0.072", motion direct.

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

position:

position (equinox 1950.0)

RA: 17h 20min 5sec

DEC: +40° 1' 21''

variability informations:

variability type	EA/D+BY	close binary eclipsing system rotating variable star
magnitute at max. brightness	5.51
magnitute amplitude	0.12
photometric system	visual, photovisual or Johnson's V

references

to a study	L.J.Boyd, R.M.Genet, D.S.Hall, W.T.Persinger, R.E.Fried, N.F.Wasson, H.J.Stelzer, R.D.Lines, P.A.Brooks, D.Hoff, IBVS No.2675,1985.
to a chart/photograph	no chart is avaible, but the star is contained in the 'Bonner Durchmusterung'

miscanellous

ID in the GCVS catalogue	40/819
constellation	Hercules
notes on existence	The star is equivalent to '68385'.

variability type description

variability type	description
EA	Eclipsing binary systems. These are binary systems with orbital planes so close to the observer's line of sight (the inclination i of the orbital plane to the plane orthogonal to the line of sight is close to 90 deg) that the components periodically eclipse each other. Consequently, the observer finds changes of the apparent combined brightness of the system with the period coincident with that of the components' orbital motion. EA Algol (Beta Persei)-type eclipsing systems. Binaries with spherical or slightly ellipsoidal components. It is possible to specify, for their light curves, the moments of the beginning and end of the eclipses. Between eclipses the light remains almost constant or varies insignificantly because of reflection effects, slight ellipsoidality of components, or physical variations. Secondary minima may be absent. An extremely wide range of periods is observed, from 0.2 to >= 10000 days. Light amplitudes are also quite different and may reach several magnitudes. EB Beta Lyrae-type eclipsing systems. These are eclipsing systems having ellipsoidal components and light curves for which it is impossible to specify the exact times of onset and end of eclipses because of a continuous change of a system's apparent combined brightness between eclipses; secondary minimum is observed in all cases, its depth usually being considerably smaller than that of the primary minimum; periods are mainly longer than 1 day. The components generally belong to early spectral types (B-A). Light amplitudes are usually <2 mag in V. EW W Ursae Majoris-type eclipsing variables. These are eclipsers with periods shorter than 1 days, consisting of ellipsoidal components almost in contact and having light curves for which it is impossible to specify the exact times of onset and end of eclipses. The depths of the primary and secondary minima are almost equal or differ insignificantly. Light amplitudes are usually <0.8 mag in V. The components generally belong to spectral types F-G and later.
D	Detached systems, with components not filling their inner Roche lobes.
BY	BY Draconis-type variables, which are emission-line dwarfs of dKe-dMe spectral type showing quasiperiodic light changes with periods from a fraction of a day to 120 days and amplitudes from several hundredths to 0.5 mag in V. The light variability is caused by axial rotation of a star with a variable degree of nonuniformity of the surface brightness (spots) and chromospheric activity. Some of these stars also show flares similar to those of UV Cet stars, and in those cases they also belong to the latter type and are simultaneously considered eruptive variables.