EE Draconis
catalogues and names
| catalogues and names | EE Dra, HR 7224, HD 177410, SAO 18103, BD +69 1018, FK5: 3517 |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
position, motion, parallax:
| position (J2000) | RA: 18h 58min 52.6sec | DEC: +69° 31' 52'' | ||
| position (B1900) | RA: 18h 59min 29.9sec | DEC: +69° 23' 20'' | ||
| proper motion (J2000) | RA: 0.005 arcsec/a | DEC: 0.004 arcsec/a | ||
| radial velocity | -15 km/s | |||
| galactic coordinates | longitude: 100.31° | latitude: 24.65° | ||
magnitude
| visual magnitude | 6.52 (V on UBV Johnson system) |
spectral / color information
| spectral class | A0pSi |
| B-V-magnitude | -0.15 |
| U-B-magnitude | -0.53 |
| note (category: spectra): | Also classified B9.5IIIpSi. |
variability information
| variable star identification | EE Dra |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 18h 58min 52.657sec | DEC: +69° 31' 51.97'' | ±0.35 arcsec | source: 34 |
| proper motion (J2000) | RA: 0.0014 arcsec/a | DEC: -0.002 arcsec/a | source: 25 | |
| radial velocity | -15 km/s | source: 25 | ||
| galactic coord. (B1950) | longitude: 100.32° | latitude: 24.65° | ||
magnitude:
| visual | 6.52 (observed) | source: 25 |
| photovisual | 6.4 | source: 2 |
| photographic | 6.4 | source: 16 |
spectral information:
| spectral class | B9 | source: 96 | |
| Morgan-Keenan | A0pSi | source: 25 | |
| B-magnitude | 6.37 ±0.05 | B-V-magnitude | -0.15 |
| U-magnitude | 5.84 ±0.05 | U-B-magnitude | -0.53 |
variability information:
| variability type | 160 |
| var. amplitude | 0 |
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 | |
| 27 | Catalog of Red Magnitudes (CRM) |
| Warren, W.H. Jr., Northern Hemisphere Catalog of Red Magnitudes, 1994 | |
| 34 | IRS Catalog |
| Corbin, T.E., 1991, U.S. Naval Observatory, International Reference Stars Catalog | |
| 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: 18h 59min 11.686sec | DEC: +69° 27' 34.99'' | ±0.064 arcsec |
| position (J2000) | RA: 18h 58min 52.958sec | DEC: +69° 31' 48.21'' | |
| proper motion B1950 (FK4) | RA: 0.0032 arcsec/a | DEC: -0.04 arcsec/a | ±0.012 arcsec/a in RA ±0.017 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: 0.0043 arcsec/a | DEC: -0.041 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 6.4 (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. |
catalogues
| source catalogue | GC, catalogue number: 26146 |
| Durchmusterung | BD+69 1018 |
| Boss General Catalogue | 26146 |
| Henry Draper Catalogue | 177410 |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
| position (equinox 1950.0) | RA: 18h 59min 11.7sec | DEC: +69° 27' 35'' |
variability informations:
| variability type | ACV | rotating variable star |
| magnitute at max. brightness | 5.84 | |
| magnitute amplitude | 0.05 | |
| photometric system |
references
| to a study | J.E.Winzer, Ph.D. Thesis, Univ Toronto,1974. |
| to a chart/photograph | no chart is avaible, but the star is contained in the 'Bonner Durchmusterung' |
miscanellous
| ID in the GCVS catalogue | 34/149 |
| constellation | Draco |
| notes on existence | The star is equivalent to '69255'. |
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. |