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Two-colour photometry for 9473 components of close Hipparcos double and multiple stars 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.
| Early type high-velocity stars in the solar neighborhood. IV - Four-color and H-beta photometry Results are presented from photometric obaservations in the Stromgrenuvby four-color and H-beta systems of early-type high-velocity stars inthe solar neighborhood. Several types of photometrically peculiar starsare selected on the basis of their Stromgren indices and areprovisionally identified as peculiar A stars, field horizontal-branchstars, metal-poor stars near the Population II and old-disk turnoffs,metal-poor blue stragglers, or metallic-line A stars. Numerousphotometrically normal stars were also found.
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Osservazione e dati astrometrici
Costellazione: | Andromeda |
Ascensione retta: | 23h19m07.72s |
Declinazione: | +48°55'10.0" |
Magnitudine apparente: | 7.241 |
Distanza: | 136.612 parsec |
Moto proprio RA: | 75.5 |
Moto proprio Dec: | 8 |
B-T magnitude: | 7.559 |
V-T magnitude: | 7.268 |
Cataloghi e designazioni:
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