Merope
catalogues and names
| catalogues and names | Merope, V0971 Tau, 23 Tau, HR 1156, HD 23480, SAO 76172, BD +23 522 |
| constellation | Taurus |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
| note (category: star names): | Merope. |
position, motion, parallax:
| position (J2000) | RA: 3h 46min 19.6sec | DEC: +23° 56' 54'' | ||
| position (2000.72) | RA: 3h 46min 23sec | DEC: +23° 57' 2'' | ||
| position (B1900) | RA: 3h 40min 23.3sec | DEC: +23° 38' 13'' | ||
| proper motion (J2000) | RA: 0.021 arcsec/a | DEC: -0.045 arcsec/a | ||
| radial velocity | 6 km/s note: variable radial velocity |
|||
| rotational velocity | 282 km/s (uncertain) (variable) | |||
| galactic coordinates | longitude: 166.57° | latitude: -23.75° | ||
magnitude
| visual magnitude | 4.18 (V on UBV Johnson system) |
spectral / color information
| spectral class | B6IVe |
| B-V-magnitude | -0.06 |
| U-B-magnitude | -0.42 |
| R-I-magnitude |
variability information
| variable star identification | V971 Tau |
| note (category: variability): | Variable hydrogen emission. |
double/multiple star system information
| note (category: double and multiple data): | Suspected double probably single star. |
miscellaneous information
| note (category: group membership): | Pleiades cluster; Mel 22 #980; in reflection nebula; Pleiades nebula; member assoc. Tau R1 at 110 pc. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 3h 46min 19.537sec | DEC: +23° 56' 53.42'' | ±0.43 arcsec | source: 16 |
| position (2000.72) | RA: 3h 46min 23sec | DEC: +23° 57' 1'' | JD: 2451809.23 | |
| proper motion (J2000) | RA: 0.0008 arcsec/a | DEC: -0.057 arcsec/a | source: 25 | |
| radial velocity | 6 km/s | source: 25 | ||
| galactic coord. (B1950) | longitude: 166.57° | latitude: -23.75° | ||
magnitude:
| visual | 4.18 (observed) | source: 25 |
| photovisual | 4.3 | source: 2 |
| photographic | 4.1 | source: 16 |
spectral information:
| spectral class | B5 | source: 96 | |
| Morgan-Keenan | B6IVe | source: 25 | |
| B-magnitude | 4.12 ±0.05 | B-V-magnitude | -0.06 |
| U-magnitude | 3.7 ±0.05 | U-B-magnitude | -0.42 |
variability information:
| variability type | 140 |
| 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 | |
| 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: 3h 43min 21.195sec | DEC: +23° 47' 38.99'' | ±0.018 arcsec |
| position (2000.72) | RA: 3h 46min 22sec | DEC: +23° 57' 4'' | JD: 2451809.23 |
| position (J2000) | RA: 3h 46min 19.589sec | DEC: +23° 56' 54.06'' | |
| proper motion B1950 (FK4) | RA: 0.0016 arcsec/a | DEC: -0.042 arcsec/a | ±0.003 arcsec/a in RA ±0.002 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: 0.0015 arcsec/a | DEC: -0.045 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 4.3 (accuracy: 2 decimals) |
| source of visual magnitude data | Taken from Harvard or San Luis photometry. |
spectral information:
| spectral class | B5 |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
catalogues
| source catalogue | GC, catalogue number: 4512 |
| Durchmusterung | BD+23 522 |
| Boss General Catalogue | 4512 |
| Henry Draper Catalogue | 23480 |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
| position (equinox 1950.0) | RA: 3h 43min 21.2sec | DEC: +23° 47' 39'' |
variability informations:
| variability type | BCEP | pulsating variable star |
| magnitute at max. brightness | 4.18 | |
| magnitute amplitude | 0.01 | |
| photometric system | visual, photovisual or Johnson's V |
references
| to a study | B.J.McNamara, ApJ 312,778,1987. |
| to a chart/photograph | no chart is avaible, but the star is contained in the 'Bonner Durchmusterung' |
miscanellous
| ID in the GCVS catalogue | 78/971 |
| constellation | Taurus |
| notes on existence | The star is equivalent to '69056'. |
variability type description
| variability type | description |
| BCEP | Variables of the Beta Cephei type (Beta Cep, Beta CMa), which are pulsating O8-B6 I-V stars with periods of light and radial-velocity variations in the range of 0.1 - 0.6 days and light amplitudes from 0.01 to 0.3 mag in V. The light curves are similar in shape to average radial-velocity curves but lag in phase by a quarter of the period, so that maximum brightness corresponds to maximum contraction, i.e., to minimum stellar radius. The majority of these stars probably show radial pulsations, but some (V649 Per) display nonradial pulsations; multiperiodicity is characteristic of many of these stars. |