Spica
| catalogues and names | Spica, a Vir, alf Vir, 67 Vir, HR 5056, HD 116658, SAO 157923, FK5: 498, WDS 13252-1110 |
| other names | Azimech, Spica Virginis, Alaraph |
| constellation | Virgo |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
| note (category: star names): | SPICA; Azimech; Spica Virginis; Alaraph, a name also given HR 4540, 4932. |
position, motion, parallax:
| position (J2000) | RA: 13h 25min 11,6sec | DEC: -11° 9' 41'' |
| position (J1900) | RA: 13h 19min 55,4sec | DEC: -10° 38' 22'' |
| proper motion (J2000) | RA: -0,041 arcsec/a | DEC: -0,028 arcsec/a |
| radial velocity | 1 km/s note: spectroscopic binaries, double lined spectra note: orbital data avaible |
|
| rotational velocity | 159 km/s (uncertain) (variable) | |
| trigonometric parallax | 0,023 arcsec | |
magnitude
| visual magnitude | 0,98 (V on UBV Johnson system) |
spectral / color information
| spectral class | B1III-IV+B2V |
| B-V-magnitude | -0,23 |
| U-B-magnitude | -0,93 |
| R-I-magnitude | -0,24 |
| note (category: spectra): | Also variously classified B2V+B2V, B1.5IV-V+B3V, B1V+B3V. Rocket observations show hydrogen lines Lyman alpha through Zeta. |
| note (category: colors): | Color excess E(B-V) = +0.03. |
variability information
| variable star identification | Alp Vir |
| note (category: variability): | Ell (Beta C) 0.97 - 1.04V, 4.01454d, and Beta C, 0.1737853d. Period changes. |
double/multiple star system information
| number of components of multiple star system | 5 |
| separation | 0 arcsec |
| mag difference (of double or brightest multiple) | 1,5 |
| component ID | O |
| note | Worley (1978) update of the IDS |
| note (category: double and multiple data): | Interferometer indicates visual component A is multiple system. Occultations yield three companions: 3.1v at 0.0025", 4.5 at 0.05" and 7.5 at 0.5". Combined mag. and colors. Visual component B, 12.0v at 148". |
| note (category: spectroscopic binaries): | 4.0145d, K 120k/s, V0 0k/s, msin3i 7.16, asini 6.52. Rotation apsides 130 yrs. Rotational velocity 190k/s. vsini secondary 102k/s. |
miscellaneous information
| note (category: stellar radii or diameters): | Diam. = 0.00085 - 0.00087". |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 13h 25min 11,587sec | DEC: -11° 9' 40,71'' | ±0,06 arcsec | source: 15 |
| proper motion (J2000) | RA: -0,0028 arcsec/a | DEC: -0,028 arcsec/a | source: 25 | |
| radial velocity | 1 km/s | source: 25 | ||
| trigonometric parallax | 0,023 | ±0,002 arcsec | source: 25 | |
| galactic coord. (B1950) | longitude: 316,13° | latitude: 50,84° | ||
| GCI unit vector (J2000) | X: -0,91408 | Y: -0,356353 | Z: -0,193572 | |
magnitude:
| visual | 0,9 (observed) | source: 31 |
| photovisual | 1,2 | source: 2 |
| photographic | 1 | source: 2 |
spectral information:
| spectral class | B2 | source: 29 | |
| Morgan-Keenan | B1III-IV+B2V | source: 25 | |
| B-magnitude | 0,75 ±0,05 | B-V-magnitude | -0,23 |
| U-magnitude | -0,18 ±0,05 | U-B-magnitude | -0,93 |
variability information:
| variability type | 10 |
| var. amplitude | 0,1 |
| var. period | 4,01 |
| var. epoch | 2419530 7. May 1912, 12:00:00 UT |
| next max light | 2451622,03 18. March 2000, 12:43:12 UT |
double/multiple star system information:
| separation between brightest and second brightest component | 147,9 arcsec |
| magnitude difference between brightest and second brightest component | 11 |
| position angle | 32 ° |
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 | |
| 29 | SAOJ2000 |
| SAO on FK5 at J2000, 1989 | |
| 30 | GCVS, 4th edition |
| Kholopov, P.N., et al., General Catalogue of Variable Stars, fourth edition, Moscow: Nauka Publishing House, 1985-88 | |
| 31 | CRM' (non-GCVS variable data) |
| Warren, W.H. Jr., Northern Hemisphere Catalog of Red Magnitudes, 1994 | |
data from Smithsonian Astrophysical Observatory Star Catalog (SAO Staff 1966; USNO, ADC 1990)
position and proper motion:
| position (J1950) | RA: 13h 22min 33,301sec | DEC: -10° 54' 3,36'' | ±0,003 arcsec |
| position (J2000) | RA: 13h 25min 11,601sec | DEC: -11° 9' 40,64'' | |
| proper motion J1950 (FK4) | RA: -0,0029 arcsec/a | DEC: -0,033 arcsec/a | ±0,001 arcsec/a in RA ±0,001 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: -0,0026 arcsec/a | DEC: -0,027 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 1,2 (accuracy: 2 decimals) |
| source of visual magnitude data | Taken from the "Henry Draper Catalogue". |
spectral information:
| spectral class | B2 |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
catalogues
| source catalogue | FK4, catalogue number: 498 |
| Durchmusterung | BD-10 3672 |
| Boss General Catalogue | 18144 |
| Henry Draper Catalogue | 116658 |
data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)
position and proper motion:
| position (J2000) | RA: 13h 25,2min | DEC: -11° 10' |
| proper motion (J2000) | RA: -0,041 arcsec/a | DEC: -0,028 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 |
| - | 1879 | 2 | 33° | 144,4'' | 0,98 | 12 | - | BUP 150 |
| 1909 | 32° | 147,9'' | ||||||
| AC | 1879 | 1 | 62° | 359,8'' | 0,98 | 10,5 | - | BUP 150 |
discoverer information:
| discoverer code | discoverer | reference |
| BUP 150 | - | - |
notes:
| note | Alpha Vir. A is an Alpha CVn-type variable and a spectroscopic binary, spectrum B1III-IV+B2V. It has been resolved by intensity interferometry. |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
| position (J1950) | RA: 13h 22min 33,3sec | DEC: -10° 54' 3'' |
variability informations:
| variability type | ELL+BCEP | rotating variable star pulsating variable star |
| magnitute at max. brightness | 0,95 | |
| magnitute amplitude | 0,1 | |
| photometric system | visual, photovisual or Johnson's V | |
| epoch for maximum light [JD] | 2419530,49 7. May 1912, 23:45:36 UT |
|
| period [d] | 4,014604 | |
| next maximum light [JD] | 2451623,234376 19. March 2000, 17:37:30 UT |
spectral information
| spectral class | B1III-IV+B2V |
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 'Bonner Durchmusterung' |
miscanellous
| ID in the GCVS catalogue | 86/9001 |
| constellation | Virgo |
| notes on existence | The star is equivalent to '0869017 rho'. |
| There are notes in published catalog. | |
variability type description
| variability type | description |
| ELL | Rotating ellipsoidal variables (b Per, Alpha Vir). These are close binary systems with ellipsoidal components, which change combined brightnesses with periods equal to those of orbital motion because of changes in emitting areas toward an observer, but showing no eclipses. Light amplitudes do not exceed 0.1 mag in V. |
| 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. |