V0638 Cassiopeiae
catalogues and names
| catalogues and names | V0638 Cas, HR 8770, HD 217833, SAO 35092, BD +54 2900, WDS 23027+5514A |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
position, motion, parallax:
| position (J2000) | RA: 23h 2min 43.8sec | DEC: +55° 14' 11'' | ||
| position (B1900) | RA: 22h 58min 25.2sec | DEC: +54° 41' 53'' | ||
| proper motion (J2000) | RA: 0.008 arcsec/a | DEC: 0.012 arcsec/a | ||
| radial velocity | -13 km/s | |||
| galactic coordinates | longitude: 107.79° | latitude: -4.41° | ||
magnitude
| visual magnitude | 6.5 (V on UBV Johnson system) |
spectral / color information
| spectral class | B9IIIHe wk |
| B-V-magnitude | -0.08 |
| U-B-magnitude | -0.55 |
variability information
| variable star identification | V638 Cas |
| note (category: variability): | Alpha CV, amp. 0.10u, 5.36d. Spectrum variable. |
double/multiple star system information
| number of components of multiple star system | 4 |
| separation | 19.5 arcsec |
| mag difference (of double or brightest multiple) | 3.6 |
| component ID | AB |
| note (category: spectroscopic binaries): | Optical. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 23h 2min 43.897sec | DEC: +55° 14' 11.76'' | ±0.35 arcsec | source: 17 |
| proper motion (J2000) | RA: 0.002 arcsec/a | DEC: 0.017 arcsec/a | source: 25 | |
| radial velocity | -13 km/s | source: 25 | ||
| galactic coord. (B1950) | longitude: 107.8° | latitude: -4.41° | ||
magnitude:
| visual | 6.5 (observed) | source: 25 |
| photovisual | 6.5 | source: 2 |
| photographic | 6.4 | source: 16 |
spectral information:
| spectral class | B9 | source: 96 | |
| Morgan-Keenan | B9IIIHewk | source: 25 | |
| B-magnitude | 6.42 ±0.05 | B-V-magnitude | -0.08 |
| U-magnitude | 5.87 ±0.05 | U-B-magnitude | -0.55 |
variability information:
| variability type | 160 |
| var. amplitude | 0.1 |
| var. period | 5.36 |
| var. epoch | 2444115 29. August 1979, 12:00:00 UT |
| next max light | 2452219.32 5. November 2001, 19:40:48 UT |
double/multiple star system information:
| separation between brightest and second brightest component | 19.5 arcsec |
| magnitude difference between brightest and second brightest component | 3.3 |
| position angle | 50 ° |
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 | |
| 16 | PPM North and PPM South Catalogs and PPM Supplement |
| Roser, S., and U. Bastian, "Catalogue of Positions and Proper Motions," A&AS, Vol. 74, p. 449, 1988, and Bastian, U., et al., "Catalogue of Positions and Proper Motions - South," 1993 | |
| 17 | ACRS |
| Corbin, T.E., and S.E. Urban, Astrographic Catalog Reference Stars, United States Naval Observatory, 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 (B1950) | RA: 23h 0min 34.09sec | DEC: +54° 58' 1.22'' | ±0.04 arcsec |
| position (J2000) | RA: 23h 2min 43.787sec | DEC: +55° 14' 11.49'' | |
| proper motion B1950 (FK4) | RA: 0.0007 arcsec/a | DEC: 0.016 arcsec/a | ±0.007 arcsec/a in RA ±0.006 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: 0.0009 arcsec/a | DEC: 0.012 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 6.5 (accuracy: 2 decimals) |
| source of visual magnitude data | Taken from Harvard or San Luis photometry. |
spectral information:
| spectral class | B9 |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
remarks for duplicity and variability
| Double star in Aitken's Double Star Catalogue (Aitken 1932) |
catalogues
| source catalogue | GC, catalogue number: 32116 |
| Durchmusterung | BD+54 2900 |
| Boss General Catalogue | 32116 |
| Henry Draper Catalogue | 217833 |
data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)
position and proper motion:
| position (J2000) | RA: 23h 2.7min | DEC: +55° 14' |
| proper motion (J2000) | RA: 0.017 arcsec/a | DEC: 0.017 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 | 1843 | 11 | 53° | 21.7'' | 6.5 | 9.8 | B9IIIHewk | STT 485 |
| 1961 | 50° | 19.5'' | ||||||
| AC | 1907 | 5 | 260° | 56.6'' | 6.5 | 10 | - | STT 485 |
| 1961 | - | 56.1'' | ||||||
| AD | 1915 | 1 | 95° | 39.8'' | 6.5 | - | B9IIIHewk | STT 485 |
discoverer information:
| discoverer code | discoverer | reference |
| STT 485 | Struve, O. | - |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
| position (equinox 1950.0) | RA: 23h 0min 34.1sec | DEC: +54° 58' 1'' |
variability informations:
| variability type | ACV | rotating variable star |
| magnitute at max. brightness | 5.7 | |
| magnitute amplitude | 0.1 | |
| photometric system | ||
| epoch for maximum light [JD] | 2444115.24 29. August 1979, 17:45:36 UT |
|
| period [d] | 5.36 | |
| next maximum light [JD] | 2452219.56 6. November 2001, 01:26:24 UT |
spectral information
| spectral class | B9IIIp(He weak) |
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 | 18/638 |
| constellation | Cassiopeia |
| notes on existence | The star is equivalent to '0180639 V0639'. |
| There are notes in published catalog. | |
variability type description
| variability type | description |
| ACV | Alpha2 Canum Venaticorum variables. These are main-sequence stars with spectral types B8p-A7p and displaying strong magnetic fields. Spectra show abnormally strong lines of Si, Sr, Cr, and rare earths whose intensities vary with rotation. They exhibit magnetic field and brightness changes (periods of 0.5-160 days or more). The amplitudes of the brightness changes are usually withine 0.01-0.1 mag in V. ACVO Rapidly oscillating Alpha2 CVn variables. These are nonradially pulsating, rotating magnetic variables of Ap spectral type (DO Eri). Pulsation periods are in the range of 6-12 mmag (0.004-0.01 days), while amplitudes of light variation caused by the pulsation are about 0.01 mag in V. The pulsational variations are superposed on those caused by rotation. |