First Double Star Observations in the HIPPARCOS Tycho Project
نویسندگان
چکیده
منابع مشابه
Comparison of the first results from the Hipparcos star mappers with the Hipparcos Input Catalogue
Preliminary positions and magnitudes derived from the analysis of 12 weeks of observations from the Hipparcos star mappers are systematically compared with the various sources of ground-based data used in the Hipparcos Input Catalogue. These comparisons allow to cross-check the accuracies claimed by the various sources of ground-based data and by the analysis method of star mapper data. The par...
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The Hipparcos and Tycho Catalogues offer an interesting possibility to study the local distribution of interstellar reddening from the combination of data contained in the catalogues: Hipparcos parallaxes, Tycho B V and spectral and luminosity classification compiled from the literature. Parallactic distances may be derived for known absorbing features such as local molecular clouds and for lar...
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ژورنال
عنوان ژورنال: International Astronomical Union Colloquium
سال: 1992
ISSN: 0252-9211
DOI: 10.1017/s0252921100006916