TYCHO-2+ for the HNSKY planetarium program
The Tycho-2+ star catalog in the HNSKY format. It is made from the combined Tycho-2 and Tycho-1 star catalogs as free available from the CDS (Centre de Données astronomiques de Strasbourg) webpage. The Tycho-2 contains 2.5 million stars. Some faint stars originally in the Tycho-1 where omitted in Tycho-2. This special Tycho-2+ version contains 6197 more stars (total 2563686 stars) then the original Tycho-2 . See article of Bill Anderson
These converted HNSKY files and this webpage have been created only to prevent that you have to download and to convert the original Tycho-2 ASCII files yourself. All legal obligations/conditions/rules as described in the CDS. webpages are still applicable/valid. As long the Tycho-2 can be downloaded free, I will provide these to HNSKY format converted files. By downloading this file you agree to all conditions/rules as described/defined in CDS.
The stars in the HNSKY files are sorted from bright to faint with an
accuracy of 0.1 magnitude. The file format is described in the HNSKY.HLP
file. Total size is about 23 Mbyte.
Hipparcos Description: The Hipparcos and Tycho Catalogues are the primary products of the European Space Agency's astrometric mission, Hipparcos. The satellite, which operated for four years, returned high quality scientific data from November 1989 to March 1993. Each of the catalogues contains a large quantity of very high quality astrometric and photometric data. In addition there are associated annexes featuring variability and double/multiple star data, and solar system astrometric and photometric measurements. In the case of the Hipparcos Catalogue, the principal parts are provided in both printed and machine-readable form (on CDROM). In the case of the Tycho Catalogue, results are provided in machine-readable form only (on CDROM). Although in general only the final reduced and calibrated astrometric and photometric data are provided, some auxiliary files containing results from intermediate stages of the data processing, of relevance for the more-specialised user, have also been retained for publication. (Some, but not all, data files are available from the Centre de Donnees astronomiques de Strasbourg.) The global data analysis tasks, proceeding from nearly 1000 Gbit of raw satellite data to the final catalogues, was a lengthy and complex process, and was undertaken by the NDAC and FAST Consortia, together responsible for the production of the Hipparcos Catalogue, and the Tycho Consortium, responsible for the production of the Tycho Catalogue. A fourth scientific consortium, the INCA Consortium, was responsible for the construction of the Hipparcos observing programme, compiling the best-available data for the selected stars before launch into the Hipparcos Input Catalogue. The production of the Hipparcos and Tycho Catalogues marks the formal end of the involvement in the mission by the European Space Agency and the four scientific consortia. For more complete and detailed information on the data, the user is advised to refer to Volume 1 ("Introduction and Guide to the Data", ESA SP-1200) of the printed Hipparcos and Tycho Catalogues.