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A photometric study of BL Herculis
Photometric observations of the prototype variable BL Her are described.The reddening, metallicity, temperature, and surface gravity of the starare determined. A Baade-Wesselink analysis is made to determine theradius and distance to the variable. The mass of the star is determinedto be 0.75 solar, placing it in the range of RR Lyrae variables. Themetallicity of +0.20, however, is greater than that of any known RRLyrae variable.
| Revised photometric properties for the multiperiodic variable HD 200925
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Osservazione e dati astrometrici
| Costellazione: | Ercole |
| Ascensione retta: | 18h01m52.04s |
| Declinazione: | +20°08'40.9" |
| Magnitudine apparente: | 8.289 |
| Distanza: | 121.065 parsec |
| Moto proprio RA: | -7.3 |
| Moto proprio Dec: | -9.9 |
| B-T magnitude: | 8.723 |
| V-T magnitude: | 8.325 |
Cataloghi e designazioni:
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