P Cyg
| catalogues and names | P Cyg, 34 Cyg, HR 7763, HD 193237, SAO 69773 |
| constellation | Cygnus |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
position, motion, parallax:
| position (J2000) | RA: 20h 17min 47,2sec | DEC: +38° 1' 59'' |
| position (J1900) | RA: 20h 14min 6sec | DEC: +37° 43' 19'' |
| proper motion (J2000) | RA: -0,005 arcsec/a | DEC: -0,004 arcsec/a |
| radial velocity | -9 km/s note: variable radial velocity |
|
| rotational velocity | 75 km/s (uncertain) (variable) | |
| trigonometric parallax | 0,004 arcsec | |
| note (category: radial and/or rotational velocities): | Outermost shell RV varies -180 to -240k/s in period 114d. Mass loss 0.0004? solar masses/y. |
magnitude
| visual magnitude | 4,81 (V on UBV Johnson system) |
spectral / color information
| spectral class | B2pe |
| B-V-magnitude | 0,42 |
| U-B-magnitude | -0,58 |
| R-I-magnitude | 0,26 |
variability information
| variable star identification | P Cyg |
| note (category: variability): | SD 3 - 6v. Since 18th century, 4.6 - 5.6v. Shell star, Nova 1600. |
miscellaneous information
| note (category: group membership): | Cyg OB1. |
| note (category: miscellaneous): | Possible radio source. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 20h 17min 47,195sec | DEC: +38° 1' 58,55'' | ±0,2 arcsec | source: 52 |
| proper motion (J2000) | RA: -0,0007 arcsec/a | DEC: -0,006 arcsec/a | source: 25 | |
| radial velocity | -9 km/s | source: 25 | ||
| trigonometric parallax | 0,004 | - | source: 25 | |
| galactic coord. (B1950) | longitude: 75,83° | latitude: 1,32° | ||
| GCI unit vector (J2000) | X: 0,445529 | Y: -0,649544 | Z: 0,616114 | |
magnitude:
| visual | 4,81 (observed) | source: 25 |
| photovisual | 4,9 | source: 2 |
| photographic | 4,7 | source: 16 |
spectral information:
| spectral class | B1 | source: 96 | |
| Morgan-Keenan | B2pe | source: 25 | |
| B-magnitude | 5,23 ±0,05 | B-V-magnitude | 0,42 |
| U-magnitude | 4,65 ±0,05 | U-B-magnitude | -0,58 |
variability information:
| variability type | 350 |
| var. amplitude | 3 |
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 | |
| 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 | |
| 52 | PPMN-HP subset |
| PPMN Star Catalogue (Reference 16) High-Precision Subset (Code H) | |
| 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: 20h 15min 56,5sec | DEC: +37° 52' 35,55'' | ±0,025 arcsec |
| position (J2000) | RA: 20h 17min 47,17sec | DEC: +38° 1' 58,87'' | |
| proper motion J1950 (FK4) | RA: -0,0007 arcsec/a | DEC: -0,002 arcsec/a | ±0,004 arcsec/a in RA ±0,003 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: -0,0004 arcsec/a | DEC: -0,004 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 4,9 (accuracy: 2 decimals) |
| source of visual magnitude data | Taken from Harvard or San Luis photometry. |
spectral information:
| spectral class | B1p |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
catalogues
| source catalogue | GC, catalogue number: 28218 |
| Durchmusterung | BD+37 3871 |
| Boss General Catalogue | 28218 |
| Henry Draper Catalogue | 193237 |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
| position (J1950) | RA: 20h 15min 56,5sec | DEC: +37° 52' 36'' |
variability informations:
| variability type | SDOR | eruptive variable star |
| magnitute at max. brightness | 3 | |
| magnitute at min. brightness | 6 | |
| photometric system | visual, photovisual or Johnson's V |
spectral information
| spectral class | B1Iapeq |
references
| to a chart/photograph | Vol. I GCVS (see Kholopov et al. 1985-1988) |
miscanellous
| ID in the GCVS catalogue | 31/9216 |
| constellation | Cygnus |
| notes on existence | The star is equivalent to '0319217 Q'. |
| There are notes in published catalog. | |
variability type description
| variability type | description |
| SDOR | Variables of the S Doradus type. These are eruptive, high-luminosity Bpec-Fpec stars showing irregular (sometimes cyclic) light changes with amplitudes in the range 1-7 mag in V. They belong to the brightest blue stars of their parent galaxies. As a rule, these stars are connected with diffuse nebulae and surrounded by expanding envelopes (P Cyg, Eta Car). |