Beschreibung:
<jats:p>The various characteristics of the HIPPARCOS Input Catalogue are described:<jats:list list-type="number"><jats:list-item><jats:label>–</jats:label><jats:p>How to select 110 000 stars for HIPPARCOS observation from the 210 000 proposed stars, taking into account the following sometimes conflicting requirements : satisfy a maximum of scientific programmes and respect the observational constraints inherent in the HIPPARCOS satellite operation ?</jats:p></jats:list-item><jats:list-item><jats:label>–</jats:label><jats:p>What are the present results regarding the principal astrometric programmes ?</jats:p></jats:list-item><jats:list-item><jats:label>–</jats:label><jats:p>How to process the specific problems which are raised by the HIPPARCOS observation of double and multiple stars and of stars in dense areas ?</jats:p></jats:list-item><jats:list-item><jats:label>–</jats:label><jats:p>Which compilations and observations have been undertaken and are in progress within the frame of the Input Catalogue preparation ? What will be the quality of the final data ?</jats:p></jats:list-item></jats:list></jats:p><jats:p>Finally, the contents of the catalogues and annexes that will be published are briefly presented.</jats:p>