Sheliak
catalogues and names | Sheliak, b Lyr, bet Lyr, 10 Lyr, HR 7106, HD 174638, SAO 67451, 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 (J1900) | 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 |
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 | 0,02 |
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 |
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° | ||
GCI unit vector (J2000) | X: 0,181056 | Y: -0,815345 | Z: 0,549937 |
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:
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 | 2451625,55 22. March 2000, 01:12:00 UT |
double/multiple star system information:
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 (J1950) | RA: 18h 48min 13,935sec | DEC: +33° 18' 12,51'' | ±0,004 arcsec |
position (J2000) | RA: 18h 50min 4,8sec | DEC: +33° 21' 45,75'' | |
proper motion J1950 (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 (J1950) | 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] | 2451625,518406 22. March 2000, 00:26:30 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. |