Suhail al Muhlif
| catalogues and names | Suhail al Muhlif, g2Vel, gam 2 Vel, HR 3207, HD 68273, SAO 219504, FK5: 309, WDS 08095-4720A |
| other names | Al Suhail al Muhlif, Spectral Gem of Southern |
| constellation | Vela |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
| note (category: star names): | Suhail al Muhlif; Al Suhail al Muhlif; "Spectral Gem of Southern Skies". |
position, motion, parallax:
| position (J2000) | RA: 8h 9min 32sec | DEC: -47° 20' 12'' |
| position (J1900) | RA: 8h 6min 27sec | DEC: -47° 2' 30'' |
| proper motion (J2000) | RA: -0,004 arcsec/a | DEC: 0,006 arcsec/a |
| radial velocity | 35 km/s note: spectroscopic binaries, double lined spectra note: orbital data avaible |
|
| trigonometric parallax | 0,017 arcsec | |
magnitude
| visual magnitude | 1,78 (V on UBV Johnson system) |
spectral / color information
| spectral class | WC8+O9I |
| B-V-magnitude | -0,22 |
| U-B-magnitude | -0,99 |
| R-I-magnitude | -0,13 |
| note (category: spectra): | Magnesium and iron depleted by factor of 100 relative to the sun. UV spectrum dominated by supergiant companions. The Wolf-Rayet component appears to be the most massive known. Radio emission indicates a circumstellar gas cloud extending beyond the orbit of the binary. Also classified WC8+O7.5e. |
variability information
| variable star identification | Gam2 Vel |
| note (category: variability): | 1.6 - 1.8V, 154 sec. Sp. var. in about 200 sec. Variability too great to be explained by the 78.5d SB companion. Possibly a third close companion: a collapsed star of less than 2 solar masses. |
double/multiple star system information
| number of components of multiple star system | 5 |
| separation | 41,2 arcsec |
| mag difference (of double or brightest multiple) | 2,3 |
| component ID | AB |
| note | Worley (1978) update of the IDS |
| note (category: double and multiple data): | See HR 3206. Mag. and colors blended with other companions. C = CoD -46d3848, 7.65V, B6V at 63", physical. D, 9.07V, Am at 94", SB, over 7d?, optical. |
| note (category: spectroscopic binaries): | Comp. A of visual double, 78.5d, K 43.1k/s, V0 -18.0k/s, asini 45.8. Alternate orbit 78.5002d, K 70k/s, V0 +12k/s, msin3i 32, asini 67. Possible mass transfer from WR to O-type component. |
miscellaneous information
| note (category: group membership): | Gamma Velorum group which includes HR 3206, probably also HD 68157 at 20' and HR 3213 at 36' from A; HII region. |
| note (category: stellar radii or diameters): | Diam. = 0.00043 - 0.00044". |
| note (category: miscellaneous): | Low degree of polarization indicates symmetric shell. The brightest O-type star and one of only four WR stars bright enough to have been observed spectroscopically in UV by COPERNICUS. With 3165, appears capable of producing most of the observed ionization of Gum Neb. The brightest and presumably the nearest Wolf-Rayet binary. Radio emission interpreted as coming from circumstellar gas cloud extending farther than the orbital radius of the binary. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 8h 9min 31,965sec | DEC: -47° 20' 11,91'' | ±0,06 arcsec | source: 15 |
| proper motion (J2000) | RA: -0,0004 arcsec/a | DEC: 0,006 arcsec/a | source: 25 | |
| radial velocity | 35 km/s | source: 25 | ||
| trigonometric parallax | 0,017 | ±0,002 arcsec | source: 25 | |
| galactic coord. (B1950) | longitude: 262,81° | latitude: -7,69° | ||
| GCI unit vector (J2000) | X: -0,362956 | Y: 0,572299 | Z: -0,735348 | |
magnitude:
| visual | 1,81 (observed) | source: 30 |
| photovisual | 1,9 | source: 2 |
spectral information:
| spectral class | O0 | source: 96 | |
| Morgan-Keenan | WC8+O9I | source: 25 | |
| B-magnitude | 1,56 ±0,05 | B-V-magnitude | -0,22 |
| U-magnitude | 0,57 ±0,05 | U-B-magnitude | -0,99 |
variability information:
| variability type | 201 |
| var. amplitude | 0,06 |
double/multiple star system information:
| separation between brightest and second brightest component | 41,3 arcsec |
| magnitude difference between brightest and second brightest component | 2,49 |
| position angle | 220 ° |
| component | magnitude | spectral class | catalogue(s)/name(s) |
| A | 1,81 | O0 | Suhail al Muhlif, g2Velorum, HR 3207, HD 68273, SAO 219504 |
| B | 4,27 | B3 | g1Velorum, HR 3206, HD 68243, SAO 219501 |
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 (J1950) | RA: 8h 7min 59,465sec | DEC: -47° 11' 18,31'' | ±0,009 arcsec |
| position (J2000) | RA: 8h 9min 31,99sec | DEC: -47° 20' 12,04'' | |
| proper motion J1950 (FK4) | RA: -0,0006 arcsec/a | DEC: 0,004 arcsec/a | ±0,002 arcsec/a in RA ±0,002 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: -0,0001 arcsec/a | DEC: 0,005 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 1,9 (accuracy: 2 decimals) |
| source of visual magnitude data | Taken from the "Henry Draper Catalogue". |
spectral information:
| spectral class | Oap |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
catalogues
| source catalogue | FK4, catalogue number: 309 |
| Durchmusterung | CD-46 3847 |
| Boss General Catalogue | 11105 |
| Henry Draper Catalogue | 68273 |
data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)
position and proper motion:
| position (J2000) | RA: 8h 9,5min | DEC: -47° 20' |
| proper motion (J2000) | RA: -0,004 arcsec/a | DEC: 0,006 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 | 1826 | 22 | 220° | 41,3'' | 1,78 | 4,27 | WC8+O7.5e | DUN 65 |
| AC | 1835 | 10 | 151° | 62,3'' | 2,2 | 8,5 | - | DUN 65 |
| AD | 1846 | 4 | 141° | 93,5'' | 2,2 | 9,4 | - | DUN 65 |
| BC | 1835 | 4 | 112° | 61'' | 6 | 8 | - | DUN 65 |
| BD | 1902 | 2 | 116° | '' | - | - | - | DUN 65 |
| CD | 1826 | 6 | 125° | 33'' | 9 | 11 | - | DUN 65 |
| DE | 1928 | 3 | 146° | 1,6'' | 9,4 | 12,8 | - | I 1175 |
discoverer information:
| discoverer code | discoverer | reference |
| DUN 65 | Dunlop, J. | - |
| I 1175 | Innes, R.T.A. | - |
notes:
| note | Gamma (2) Vel. B is CD-46@3846, Gamma (1) Vel. Both components are spectroscopic binaries, and B is variable. A is probably the nearest Wolf-Rayet system. Spectrum: WC8+O7.5e. Spectrum of B B1IV. DE: DE is I 1175 (= RST 4878) at 08 09.5 -47 25. |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
| position (J1950) | RA: 8h 7min 59,5sec | DEC: -47° 11' 18'' |
variability informations:
| variability type | WR | eruptive variable star |
| magnitute at max. brightness | 1,81 | |
| magnitute at min. brightness | 1,87 | |
| photometric system | visual, photovisual or Johnson's V |
spectral information
| spectral class | WC8+O9I |
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 'Cordoba Durchmusterung' |
miscanellous
| ID in the GCVS catalogue | 85/90032 |
| constellation | Vela |
| notes on existence | The star is equivalent to '0859011 lam'. |
| There are notes in published catalog. | |
variability type description
| variability type | description |
| WR | Eruptive Wolf-Rayet variables. Stars with broad emission features of He I and He II as well as C II-C IV, O II-O IV, and N III-N V. They display irregular light changes with amplitudes up to 0.1 mag in V, which are probably caused by physical processes, in particular, by nonstable mass outflow from their atmospheres. |