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Using observations obtained with the Tycho instrument of the ESAHipparcos satellite, a two-colour photometry is produced for componentsof more than 7 000 Hipparcos double and multiple stars with angularseparations 0.1 to 2.5 arcsec. We publish 9473 components of 5173systems with separations above 0.3 arcsec. The majority of them did nothave Tycho photometry in the Hipparcos catalogue. The magnitudes arederived in the Tycho B_T and V_T passbands, similar to the Johnsonpassbands. Photometrically resolved components of the binaries withstatistically significant trigonometric parallaxes can be put on an HRdiagram, the majority of them for the first time. Based on observationsmade with the ESA Hipparcos satellite.
| Interstellar reddening in the Southern Hemisphere. I - The UVBY beta observations
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| Estimation of spectral classifications for bright southern stars with interesting Stromgren indices
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| On the decline stage of Nova V 3888 SGR /1974/
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Datos observacionales y astrométricos
| Constelación: | Sagitario |
| Ascensión Recta: | 17h47m27.09s |
| Declinación: | -18°06'25.6" |
| Magnitud Aparente: | 7.554 |
| Distancia: | 137.363 parsecs |
| Movimiento Propio en Ascensión Recta: | 7.8 |
| Movimiento Propio en Declinación: | -4 |
| B-T magnitude: | 7.888 |
| V-T magnitude: | 7.582 |
Catálogos y designaciones:
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