u Cygni
catalogues and names
| catalogues and names | u Cyg, ups Cyg, 66 Cyg, HR 8146, HD 202904, SAO 71173, BD +34 4371, FK5: 1559, WDS 21179+3454A |
| constellation | Cygnus |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
position, motion, parallax:
| position (J2000) | RA: 21h 17min 55.1sec | DEC: +34° 53' 49'' | ||
| position (B1900) | RA: 21h 13min 48.3sec | DEC: +34° 28' 37'' | ||
| proper motion (J2000) | RA: 0.014 arcsec/a | DEC: -0.002 arcsec/a | ||
| radial velocity | 4 km/s note: spectroscopic binaries |
|||
| rotational velocity | 261 km/s (uncertain) (variable) | |||
| trigonometric parallax | 0.019 arcsec | |||
| galactic coordinates | longitude: 80.98° | latitude: -10.05° | ||
magnitude
| visual magnitude | 4.43 (V on UBV Johnson system) |
spectral / color information
| spectral class | B2Vne |
| B-V-magnitude | -0.11 |
| U-B-magnitude | -0.82 |
| R-I-magnitude |
variability information
| variable star identification | Ups Cyg |
| note (category: variability): | 4.28 - 4.50V. |
double/multiple star system information
| number of components of multiple star system | 3 |
| separation | 15.3 arcsec |
| mag difference (of double or brightest multiple) | 6.4 |
| component ID | AB |
| note (category: double and multiple data): | AB CPM; 79000?y. Component B, 10.0v G8.5V, probably optical. |
| note (category: spectroscopic binaries): | ADS 14831A. Expanding circumstellar shell. |
miscellaneous information
| note (category: group membership): | Cyg OB4. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 21h 17min 55.078sec | DEC: +34° 53' 48.68'' | ±0.06 arcsec | source: 15 |
| proper motion (J2000) | RA: 0.0012 arcsec/a | DEC: -0.002 arcsec/a | source: 25 | |
| radial velocity | 4 km/s | source: 25 | ||
| trigonometric parallax | 0.019 arcsec | ±0.002 arcsec | source: 25 | |
| galactic coord. (B1950) | longitude: 80.98° | latitude: -10.05° | ||
magnitude:
| visual | 4.225 (observed) | source: 31 |
| photovisual | 4.4 | source: 2 |
spectral information:
| spectral class | B3 | source: 96 | |
| Morgan-Keenan | B2Vne | source: 25 | |
| B-magnitude | 4.32 ±0.05 | B-V-magnitude | -0.11 |
| U-magnitude | 3.5 ±0.05 | U-B-magnitude | -0.82 |
variability information:
| variability type | 264 |
| var. amplitude | 0.22 |
double/multiple star system information:
| separation between brightest and second brightest component | 15.1 arcsec |
| magnitude difference between brightest and second brightest component | 5.6 |
| position angle | 220 ° |
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 | |
| 31 | CRM' (non-GCVS variable data) |
| Warren, W.H. Jr., Northern Hemisphere Catalog of Red Magnitudes, 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 (B1950) | RA: 21h 15min 51.555sec | DEC: +34° 41' 9.87'' | ±0.006 arcsec |
| position (J2000) | RA: 21h 17min 55.072sec | DEC: +34° 53' 48.58'' | |
| proper motion B1950 (FK4) | RA: 0.0009 arcsec/a | DEC: 0 arcsec/a | ±0.002 arcsec/a in RA ±0.001 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: 0.0011 arcsec/a | DEC: -0.003 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 4.4 (accuracy: 2 decimals) |
| source of visual magnitude data | Taken from the "Henry Draper Catalogue". |
spectral information:
| spectral class | B3p |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
catalogues
| source catalogue | FK4, catalogue number: 1559 |
| Durchmusterung | BD+34 4371 |
| Boss General Catalogue | 29802 |
| Henry Draper Catalogue | 202904 |
data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)
position and proper motion:
| position (J2000) | RA: 21h 17.9min | DEC: +34° 54' |
| proper motion (J2000) | RA: 0.014 arcsec/a | DEC: -0.002 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 | 1849 | 13 | 220° | 15.1'' | 4.43 | 10 | B2Vne | STT 433 |
| AC | 1849 | 14 | 177° | 21.2'' | 4.43 | 10 | - | STT 433 |
| 1982 | 183° | 21.2'' | ||||||
| AD | 1982 | 1 | 308° | 57.3'' | 4.4 | 12 | - | SLE 382 |
| BC | 1946 | 1 | 137° | 13.6'' | 10 | 10 | - | STT 433 |
discoverer information:
| discoverer code | discoverer | reference |
| STT 433 | Struve, O. | - |
| SLE 382 | Soulie, G. | - |
notes:
| note | Upsilon Cyg. Burnham refers to a star twice the distance of C in 60@. A Variable? |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
| position (equinox 1950.0) | RA: 21h 15min 51.6sec | DEC: +34° 41' 10'' |
variability informations:
| variability type | GCAS | eruptive variable star |
| magnitute at max. brightness | 4.28 | |
| magnitute at min. brightness | 4.5 | |
| photometric system | visual, photovisual or Johnson's V |
spectral information
| spectral class | B2Vne |
references
| to a chart/photograph | no chart is avaible, but the star is contained in the 'Bonner Durchmusterung' |
miscanellous
| ID in the GCVS catalogue | 31/9020 |
| constellation | Cygnus |
| notes on existence | The star is equivalent to '0319022 khi'. |
| There are notes in published catalog. | |
variability type description
| variability type | description |
| GCAS | Eruptive irregular variables of the Gamma Cas type. These are rapidly rotating B III-IVe stars with mass outflow from their equatorial zones. The formation of equatorial rings or disks is often accompanied by temporary fading. Light amplitudes may reach 1.5 mag in V. |