o Draconis
catalogues and names
| catalogues and names | o Dra, omi Dra, 47 Dra, HR 7125, HD 175306, SAO 31218, BD +59 1925 A, FK5: 707, WDS 18512+5923A |
| constellation | Draco |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
position, motion, parallax:
| position (J2000) | RA: 18h 51min 12.1sec | DEC: +59° 23' 18'' | ||
| position (B1900) | RA: 18h 49min 43.5sec | DEC: +59° 15' 58'' | ||
| proper motion (J2000) | RA: 0.079 arcsec/a | DEC: 0.027 arcsec/a | ||
| radial velocity | -20 km/s note: spectroscopic binaries, single lined spectra note: orbital data avaible |
|||
| rotational velocity | 20 km/s (uncertain) (variable) | |||
| trigonometric parallax | 0.006 arcsec | |||
| galactic coordinates | longitude: 89.31° | latitude: 23.14° | ||
magnitude
| visual magnitude | 4.66 (V on UBV Johnson system) |
spectral / color information
| spectral class | G9IIIFe-0.5 |
| B-V-magnitude | 1.19 |
| U-B-magnitude | 1.04 |
| R-I-magnitude | |
| IR-note | object is infrared source (NASA merged infrared catalogue, Schmitz et al., 1978) |
variability information
| variable star identification | Omi Dra |
double/multiple star system information
| number of components of multiple star system | 3 |
| separation | 34.6 arcsec |
| mag difference (of double or brightest multiple) | 3.4 |
| component ID | AB |
| note (category: double and multiple data): | B is K3IIIp optical, vsini =<54k/s. C, 11.5v at 139" is receding from A. |
| note (category: spectroscopic binaries): | ADS 11799A, 138.420d, K 23.5k/s, V0 -19.5k/s, asini 44.5. Companion possibly early type. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 18h 51min 12.083sec | DEC: +59° 23' 18.13'' | ±0.06 arcsec | source: 15 |
| proper motion (J2000) | RA: 0.0104 arcsec/a | DEC: 0.027 arcsec/a | source: 25 | |
| radial velocity | -20 km/s | source: 25 | ||
| trigonometric parallax | 0.006 arcsec | ±0.001 arcsec | source: 25 | |
| galactic coord. (B1950) | longitude: 89.31° | latitude: 23.14° | ||
magnitude:
| visual | 4.66 (observed) | source: 25 |
| photovisual | 4.8 | source: 2 |
spectral information:
| spectral class | K0 | source: 29 | |
| Morgan-Keenan | G9IIIFe-0.5 | source: 25 | |
| B-magnitude | 5.85 ±0.05 | B-V-magnitude | 1.19 |
| U-magnitude | 6.89 ±0.05 | U-B-magnitude | 1.04 |
variability information:
| variability type | 273 |
| var. amplitude | 0.1 |
double/multiple star system information:
| separation between brightest and second brightest component | 34.6 arcsec |
| magnitude difference between brightest and second brightest component | 3.2 |
| position angle | 324 ° |
| component | magnitude | spectral class | catalogue(s)/name(s) |
| A | 4.66 | K0 | o Draconis, 47 Dra, HR 7125, HD 175306, SAO 31218 |
| B | 8.192 | - |
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 | |
| 27 | Catalog of Red Magnitudes (CRM) |
| Warren, W.H. Jr., Northern Hemisphere Catalog of Red Magnitudes, 1994 | |
| 29 | SAOJ2000 |
| SAO on FK5 at J2000, 1989 | |
data from Smithsonian Astrophysical Observatory Star Catalog (SAO Staff 1966; USNO, ADC 1990)
position and proper motion:
| position (B1950) | RA: 18h 50min 27.777sec | DEC: +59° 19' 36.36'' | ±0.004 arcsec |
| position (J2000) | RA: 18h 51min 12.066sec | DEC: +59° 23' 18.15'' | |
| proper motion B1950 (FK4) | RA: 0.0095 arcsec/a | DEC: 0.027 arcsec/a | ±0.001 arcsec/a in RA ±0.001 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: 0.0102 arcsec/a | DEC: 0.027 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 the "Henry Draper Catalogue". |
spectral information:
| spectral class | K0 |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
catalogues
| source catalogue | FK4, catalogue number: 707 |
| Durchmusterung | BD+59 1925A |
| Boss General Catalogue | 25905 |
| Henry Draper Catalogue | 175306 |
data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)
position and proper motion:
| position (J2000) | RA: 18h 51.2min | DEC: +59° 23' |
| proper motion (J2000) | RA: 0.079 arcsec/a | DEC: 0.027 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 | 1832 | 51 | 346° | 30.3'' | 4.66 | 7.9 | G7III-IV | STF2420 |
| 1961 | 324° | 34.6'' | ||||||
| AC | 1880 | 3 | 327° | 107.8'' | 4.8 | 11.5 | - | STF2420 |
| 1960 | 326° | 139.4'' |
discoverer information:
| discoverer code | discoverer | reference |
| STF2420 | Struve, F.G.W. | - |
notes:
| note | Omicron Dra. A is a spectroscopic binary. Proper motion of B -016 +020. A is also variable. |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
| position (equinox 1950.0) | RA: 18h 50min 27.8sec | DEC: +59° 19' 36'' |
variability informations:
| variability type | RS | eruptive variable star |
| magnitute at max. brightness | 4.63 | |
| magnitute amplitude | 0.1 | |
| photometric system | visual, photovisual or Johnson's V |
references
| to a study | D.S.Hall, W.T.Persinger, Cool Stars,Stellar Systems,and the Sun (Lecture Notes in Physics 254),88,1986. |
| to a chart/photograph | no chart is avaible, but the star is contained in the 'Bonner Durchmusterung' |
miscanellous
| ID in the GCVS catalogue | 34/9015 |
| constellation | Draco |
| notes on existence | The star is equivalent to '69253'. |
variability type description
| variability type | description |
| RS | Eruptive variables of the RS Canum Venaticorum type. This type is ascribed to close binary systems with spectra showing Ca II H and K in emission, their components having enhanced chromospheric activity that causes quasi-periodic light variability. The period of variation is close to the orbital one, and the variability amplitude is usually as great as 0.2 mag in V (UX Ari). They are X-ray sources and rotating variables. RS CVn itself is also an eclipsing system. |