Algenib
| catalogues and names | Algenib, g Peg, gam Peg, 88 Peg, HR 39, HD 886, SAO 91781, FK5: 7, WDS 00132+1511A |
| constellation | Pegasus |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
| note (category: star names): | ALGENIB. |
position, motion, parallax:
| position (J2000) | RA: 0h 13min 14,2sec | DEC: +15° 11' 1'' |
| position (J1900) | RA: 0h 8min 5,1sec | DEC: +14° 37' 40'' |
| proper motion (J2000) | RA: 0,003 arcsec/a | DEC: -0,012 arcsec/a |
| radial velocity | 4 km/s note: spectroscopic binaries note: orbital data avaible |
|
| rotational velocity | 3 km/s (uncertain) (variable) | |
| trigonometric parallax | -0,002 arcsec | |
| note (category: radial and/or rotational velocities): | RV also varies with period 0.151750125d. |
magnitude
| visual magnitude | 2,83 (V on UBV Johnson system) |
spectral / color information
| spectral class | B2IV |
| B-V-magnitude | -0,23 |
| U-B-magnitude | -0,87 |
| R-I-magnitude | -0,19 |
| note (category: spectra): | Lyman beta observed from COPERNICUS. Chlorine in spectrum. |
| note (category: colors): | Color excess E(B-V) = +0.01. |
variability information
| variable star identification | Gam Peg |
| note (category: variability): | Beta C 2.80 - 2.87V, 0.1517495d. |
double/multiple star system information
| number of components of multiple star system | 3 |
| separation | 163,4 arcsec |
| mag difference (of double or brightest multiple) | 8,9 |
| component ID | AB |
| note | Worley (1978) update of the IDS |
| note (category: spectroscopic binaries): | 6.830713d, K 1.34k/s, V0 2.5k/s, asini 0.181Solar R. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 0h 13min 14,154sec | DEC: +15° 11' 0,8'' | ±0,06 arcsec | source: 15 |
| proper motion (J2000) | RA: 0,0002 arcsec/a | DEC: -0,012 arcsec/a | source: 25 | |
| radial velocity | 4 km/s | source: 25 | ||
| galactic coord. (B1950) | longitude: 109,45° | latitude: -46,68° | ||
| GCI unit vector (J2000) | X: 0,963483 | Y: 0,055705 | Z: 0,261912 | |
magnitude:
| visual | 2,83 (observed) | source: 20 |
| photovisual | 2,9 | source: 2 |
spectral information:
| spectral class | B2 | source: 96 | |
| Morgan-Keenan | B2IV | source: 25 | |
| B-magnitude | 2,6 ±0,011 | B-V-magnitude | -0,23 |
| U-magnitude | 1,73 ±0,013 | U-B-magnitude | -0,86 |
variability information:
| variability type | 140 |
| var. amplitude | 0,11 |
| var. period | 0,15 |
| var. epoch | 2441225 30. September 1971, 12:00:00 UT |
| next max light | 2451621,35 17. March 2000, 20:24:00 UT |
double/multiple star system information:
| separation between brightest and second brightest component | 163,4 arcsec |
| magnitude difference between brightest and second brightest component | 9 |
| position angle | 286 ° |
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 | |
| 20 | Catalogue of Homogeneous Means in the UBV System |
| Mermilliod, J.C., Catalogue of Homogeneous Means in the UBV System, Institut d'Astronomie, Universite de Lausanne, 1994 | |
| 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: 0h 10min 39,447sec | DEC: +14° 54' 20,57'' | ±0,003 arcsec |
| position (J2000) | RA: 0h 13min 14,156sec | DEC: +15° 11' 0,8'' | |
| proper motion J1950 (FK4) | RA: 0,0002 arcsec/a | DEC: -0,007 arcsec/a | ±0,001 arcsec/a in RA ±0,001 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: 0,0002 arcsec/a | DEC: -0,012 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 | B2 |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
catalogues
| source catalogue | FK4, catalogue number: 7 |
| Durchmusterung | BD+14 14 |
| Boss General Catalogue | 238 |
| Henry Draper Catalogue | 886 |
data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)
position and proper motion:
| position (J2000) | RA: 0h 13,2min | DEC: +15° 11' |
| proper motion (J2000) | RA: 0,003 arcsec/a | DEC: -0,012 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 | 2 | 286° | 161,8'' | 2,83 | 11,8 | B2IV | BUP 3 |
| 1907 | - | 163,4'' | ||||||
| BC | 1879 | 2 | 199° | 21'' | 11,8 | 12,4 | - | BUP 3 |
| 1907 | 196° | 20,4'' |
discoverer information:
| discoverer code | discoverer | reference |
| BUP 3 | - | - |
notes:
| note | Gamma Peg. Beta CMa variable and spectroscopic binary. |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
| position (J1950) | RA: 0h 10min 39,4sec | DEC: +14° 54' 21'' |
variability informations:
| variability type | BCEP | pulsating variable star |
| magnitute at max. brightness | 2,78 | |
| magnitute at min. brightness | 2,89 | |
| photometric system | visual, photovisual or Johnson's V | |
| epoch for maximum light [JD] | 2441224,64 30. September 1971, 03:21:36 UT |
|
| period [d] | 0,151750125 | |
| next maximum light [JD] | 2451621,344564 17. March 2000, 20:16:10 UT |
|
| rising time | 50 % of period |
spectral information
| spectral class | B2IV |
references
| to a study | Vol. III GCVS |
| to a chart/photograph | Vol. I GCVS (see Kholopov et al. 1985-1988) |
miscanellous
| ID in the GCVS catalogue | 62/9003 |
| constellation | Pegasus |
| notes on existence | The star is equivalent to '0629005 eps'. |
variability type description
| variability type | description |
| 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. |