Graffias
| catalogues and names | Graffias, b1Sco, NSV 07424, 8 Sco, HR 5984, HD 144217, SAO 159682, FK5: 597, WDS 16054-1948A |
| other names | Grafias, Grassias, Acrab, Akrab, Elacrab |
| constellation | Scorpius |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
| note (category: star names): | Graffias; Grafias; Grassias; Acrab; Akrab; Elacrab. |
position, motion, parallax:
| position (J2000) | RA: 16h 5min 26,2sec | DEC: -19° 48' 20'' |
| position (J1900) | RA: 15h 59min 37,2sec | DEC: -19° 31' 54'' |
| proper motion (J2000) | RA: -0,006 arcsec/a | DEC: -0,019 arcsec/a |
| radial velocity | -1 km/s note: spectroscopic binaries note: orbital data avaible |
|
| rotational velocity | 130 km/s (uncertain) (variable) | |
| trigonometric parallax | 0,009 arcsec | |
| note (category: dynamical parallaxes): | 0.004". |
magnitude
| visual magnitude | 2,62 (V on UBV Johnson system) |
spectral / color information
| spectral class | B1V |
| B-V-magnitude | -0,07 |
| U-B-magnitude | -0,87 |
| R-I-magnitude | -0,09 |
| note (category: spectra): | Ca and Na lines nearly stationary. |
variability information
| variable star identification | 7424 |
double/multiple star system information
| number of components of multiple star system | 5 |
| separation | 0 arcsec |
| mag difference (of double or brightest multiple) | 1,3 |
| component ID | O |
| note (category: double and multiple data): | CPM with HR 5985 = ADS 9913C, at 14" and with B, 5.9v at 0.5", possibly SB. Lunar occultations and speckle interferometry indicate companions 4.2v at 0.001" from A and 7.6v at 0.129" from C. Occultations by Jupiter and Io in 1971 indicate complex system. Component C occulted by Io revealed the 2.5 mag. fainter companion at 0.1". |
| note (category: spectroscopic binaries): | ADS 9913AD, 6.8281d, K 129.0k/s, V0 -1.0k/s, msin3i 16.0, asini 11.6. Mag. difference about 1v. Apsidal period 51000 times orbital. Unresolved by speckle interferometry. Possible third SB component. |
miscellaneous information
| note (category: group membership): | Sco OB2; Sco-Cen assoc.; probable member of Sco-Cen cluster; upper Sco region. |
| note (category: stellar radii or diameters): | From occult. by Jupiter, diam. Beta Sco A1 = 0.000422"; diam. Beta Sco A2 = 0.000264". |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 16h 5min 26,233sec | DEC: -19° 48' 19,5'' | ±0,06 arcsec | source: 15 |
| proper motion (J2000) | RA: -0,0004 arcsec/a | DEC: -0,019 arcsec/a | source: 25 | |
| radial velocity | -1 km/s | source: 25 | ||
| trigonometric parallax | 0,009 | ±0,001 arcsec | source: 25 | |
| galactic coord. (B1950) | longitude: 353,2° | latitude: 23,6° | ||
| GCI unit vector (J2000) | X: -0,450963 | Y: -0,825729 | Z: -0,338827 | |
magnitude:
| visual | 2,62 (observed) | source: 25 |
| photovisual | 2,9 | source: 2 |
| photographic | 2,7 | source: 2 |
spectral information:
| spectral class | B1 | source: 96 | |
| Morgan-Keenan | B1V | source: 25 | |
| B-magnitude | 2,55 ±0,05 | B-V-magnitude | -0,07 |
| U-magnitude | 1,68 ±0,05 | U-B-magnitude | -0,87 |
variability information:
| variability type | 9 |
| var. amplitude | 0,06 |
double/multiple star system information:
| separation between brightest and second brightest component | 0,4 arcsec |
| magnitude difference between brightest and second brightest component | 8 |
| position angle | 146 ° |
| component | magnitude | spectral class | catalogue(s)/name(s) |
| A | 2,62 | B1 | Graffias, b1Scorpii, 8 Sco, HR 5984, HD 144217, SAO 159682 |
| B | 4,92 | B1 | b2Scorpii, 8 Sco, HR 5985, HD 144218, SAO 159683 |
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 | |
| 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: 16h 2min 31,507sec | DEC: -19° 40' 12,45'' | ±0,004 arcsec |
| position (J2000) | RA: 16h 5min 26,238sec | DEC: -19° 48' 19,37'' | |
| proper motion J1950 (FK4) | RA: -0,0004 arcsec/a | DEC: -0,021 arcsec/a | ±0,001 arcsec/a in RA ±0,001 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: -0,0003 arcsec/a | DEC: -0,018 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 2,9 (accuracy: 2 decimals) |
| source of visual magnitude data | Taken from the "Henry Draper Catalogue". |
spectral information:
| spectral class | B1 |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
catalogues
| source catalogue | FK4, catalogue number: 597 |
| Durchmusterung | BD-19 4307 |
| Boss General Catalogue | 21609 |
| Henry Draper Catalogue | 144217 |
data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)
position and proper motion:
| position (J2000) | RA: 16h 5,4min | DEC: -19° 48' |
| proper motion (J2000) | RA: -0,006 arcsec/a | DEC: -0,019 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 | 1879 | 34 | 88° | 0,9'' | 2,62 | 10,6 | B1V | BU 947 |
| 1991 | 146° | 0,4'' | ||||||
| AC | 1823 | 58 | 24° | 13,6'' | 2,62 | 4,92 | B2V | H 7 |
| 1980 | 21° | - | ||||||
| CE | 1976 | 10 | 359° | 0,1'' | 4,9 | - | - | MCA 42 |
| 1989 | 121° | - |
discoverer information:
| discoverer code | discoverer | reference |
| BU 947 | Burnham, S.W. | - |
| H 7 | Herschel, W. | - |
| MCA 42 | McAlister, H.A. | - |
notes:
| note | Beta (1) Sco. Common Proper motion with Beta (2) Sco. Speckle and occultation measures indicate a complex multiple system. H III 7. C is, Beta (2) Sco, and is a close interferometer pair found by McAlister. |
data from Combined General Catalogue of Variable Stars (suspected variables) (Kholopov+ 1998)
position:
| position (J1950) | RA: 16h 2min 31,5sec | DEC: -19° 40' 12'' |
variability informations:
| magnitute at max. brightness | 2,61 |
| magnitute at min. brightness | 2,67 |
| photometric system | visual, photovisual or Johnson's V |
spectral information
| spectral class | * |
references
| to a study | 2472D (designation: BETA SCO) |
miscanellous
| There are notes in the published catalog (Kukarkin et al.(1982)). |