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	Sheliak, b Lyr, bet Lyr, 10 Lyr, HR 7106, HD 174638, SAO 67451, BD +33 3223, FK5: 705, WDS 18501+3322A
other names	Shelyak, Shiliak
constellation	Lyra

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

note (category: star names):

Sheliak; Shelyak; Shiliak.

position, motion, parallax:

position (J2000)	RA: 18h 50min 4.8sec	DEC: +33° 21' 46''
position (2000.73)	RA: 18h 50min 7sec	DEC: +33° 21' 49''
position (B1900)	RA: 18h 46min 23.2sec	DEC: +33° 14' 47''
proper motion (J2000)	RA: 0.003 arcsec/a	DEC: -0.003 arcsec/a
radial velocity	-19 km/s note: spectroscopic binaries note: orbital data avaible
trigonometric parallax	-0.002 arcsec
galactic coordinates	longitude: 63.19°	latitude: 14.78°

magnitude

visual magnitude

3.45 (V on UBV Johnson system)

spectral / color information

spectral class	B8IIpe
B-V-magnitude	0
U-B-magnitude	-0.56
R-I-magnitude
IR-note	object is infrared source (NASA merged infrared catalogue, Schmitz et al., 1978)

note (category: spectra):

Shell star. Far UV COPERNICUS spectrum shows many emission lines, some with P Cygni profiles, presumably originating from a hotter source than the visual primary. Helium I line 10830 arises in outermost envelope which surrounds the Beta Lyrae system as a whole. Radio and X-ray source.

note (category: colors):

Large infrared excess.

variability information

variable star identification

Bet Lyr

note (category: variability):

ADS 11745A, EB 3.25 - 4.36V, 12.913834d. Period varies. Presumed disk around secondary. Also radio flare activity. Prototype Beta Lyrae type, discovered by Goodricke in 1874.

double/multiple star system information

number of components of multiple star system	6
separation	45.7 arcsec
mag difference (of double or brightest multiple)	5.2
component ID	AB

note (category: double and multiple data):

AB fixed. B is 8.6v, B7v; may be collapsed star; vsini 120k/s. E, 9.9v A8pSr or B9V at 67" optical? F, 9.9v A8-9V or or B9V at 86". A, B, E and F are CPM.

note (category: spectroscopic binaries):

ADS 11745A, 12.9349d, K 184.0k/s, V0 -17.8k/s, asini 32.7. Also 4.2y. Possible radio binary. ADS 11745B also SB, 4.34d, K 12.0k/s, V0 -29.4k/s, asini 0.695.

miscellaneous information

note (category: group membership):

Member of the local association (Pleiades group).

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

position, motion, parallax:

position (J2000)	RA: 18h 50min 4.8sec	DEC: +33° 21' 45.65''	±0.06 arcsec	source: 15
position (2000.73)	RA: 18h 50min 7sec	DEC: +33° 21' 49''	JD: 2451810.11
proper motion (J2000)	RA: 0.0003 arcsec/a	DEC: -0.003 arcsec/a		source: 25
radial velocity	-19 km/s			source: 25
galactic coord. (B1950)	longitude: 63.19°	latitude: 14.78°

magnitude:

visual

3.45 (observed)

source: 25

spectral information:

spectral class	+++		source: 29
Morgan-Keenan	B8IIpe		source: 25
B-magnitude	3.45 ±0.05	B-V-magnitude	0
U-magnitude	2.89 ±0.05	U-B-magnitude	-0.56

variability information:

source of data: 27

variability type	320
var. amplitude	1.2
var. period	12.91
var. epoch	2408247.95 16. June 1881, 10:48:00 UT
next max light	2451819.2 1. October 2000, 16:48:00 UT

double/multiple star system information:

source of data: 19

separation between brightest and second brightest component	45.7 arcsec
magnitude difference between brightest and second brightest component	5.2
position angle	149 °

component	magnitude	spectral class	catalogue(s)/name(s)
A	3.45	+++	Sheliak, b Lyrae, 10 Lyr, HR 7106, HD 174638, SAO 67451
B	7.22	B3

sources:

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
27	Catalog of Red Magnitudes (CRM)
Warren, W.H. Jr., Northern Hemisphere Catalog of Red Magnitudes, 1994
29	SAOJ2000
SAO on FK5 at J2000, 1989

data from Smithsonian Astrophysical Observatory Star Catalog (SAO Staff 1966; USNO, ADC 1990)

position and proper motion:

position (B1950)	RA: 18h 48min 13.935sec	DEC: +33° 18' 12.51''	±0.004 arcsec
position (2000.73)	RA: 18h 50min 6sec	DEC: +33° 21' 49''	JD: 2451810.11
position (J2000)	RA: 18h 50min 4.8sec	DEC: +33° 21' 45.75''
proper motion B1950 (FK4)	RA: 0 arcsec/a	DEC: -0.002 arcsec/a	±0.001 arcsec/a in RA ±0.001 arcsec/a in DEC
proper motion J2000 (FK5)	RA: 0.0003 arcsec/a	DEC: -0.002 arcsec/a
source of proper motion data	Determined by source catalog

magnitude:

visual	3.9 (accuracy: 2 decimals)
source of visual magnitude data	Arithmetic mean of maximum and minimum magnitudes of a variable star

spectral information:

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

remarks for duplicity and variability

Variable star in visual magnitude in source catalog

catalogues

source catalogue	FK4, catalogue number: 705
Durchmusterung	BD+33 3223
Boss General Catalogue	25847
Henry Draper Catalogue	174638

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

position and proper motion:

position (J2000)	RA: 18h 50.1min	DEC: +33° 22'
proper motion (J2000)	RA: 0.003 arcsec/a	DEC: -0.003 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
AB	1835	33	149°	45.7''	3.4	8.6	B7Ve+A8p	STF 39
AC	1878	3	248°	46.6''	-	13	-	BU 293
AD	1898	1	68°	64.3''	-	14.3	-	BU 293
AE	1879	11	318°	66.9''	3.4	9.9	-	BU 293
AF	1879	11	19°	85.8''	3.4	9.9	-	BU 293
	1959		-	86''

discoverer information:

discoverer code	discoverer	reference
STF 39	Struve, F.G.W.	-
BU 293	Burnham, S.W.	-

notes:

note	Beta Lyrae. A is the prototype variable of its class. B is BD+33@3224. Proper motion of B -014 -013.

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

position:

position (equinox 1950.0)

RA: 18h 48min 13.9sec

DEC: +33° 18' 13''

variability informations:

variability type	EB	close binary eclipsing system
magnitute at max. brightness	3.25
magnitute at min. brightness	4.36
photometric system	visual, photovisual or Johnson's V
epoch for maximum light [JD]	2408247.95 16. June 1881, 10:48:00 UT
period [d]	12.913834
next maximum light [JD]	2451819.225916 1. October 2000, 17:25:19 UT

spectral information

spectral class

B8II-IIIep

references

to a study	Vol. I GCVS (see Kholopov et al. 1985-1988)
to a chart/photograph	Vol. I GCVS (see Kholopov et al. 1985-1988)

miscanellous

ID in the GCVS catalogue	52/9002
constellation	Lyra
notes on existence	The star is equivalent to '05290042del 2'.
There are notes in published catalog.

variability type description

variability type

description

EB

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.