USNO is making the USNO-SA2.0 catalog (54,787,624 stars in all on one CD-ROM) available for free. The full USNO-A2.0 catalog (526,230,881 stars on 10 CD-ROMs) is also available provided you can provide a brief explanation of why USNO-SA2.0 is not sufficient. That's information on over half a billion stars!

European Space Agency's Hipparcos mission. Research tools, news, catalogues, education resources, and data.

A form that gives access to the catalogue of results from the Hipparcos mission.

The Double Star Library hopes to be a means by which various types of binary and multiple star information can be easily disseminated among binary star astronomers in IAU Commission 26 and related commissions.

Table with details about the 50 nearest stars. Names, distances, constellations, spectral types, magnitudes and coordinates.

A spectroscopic survey of 3600 nearby stars within 40pcs earlier than M0. Contains real-time spectral plots, and coordinate lists. Also MK standards.

Provides access to the all-sky astrometric and photometric catalogue from the set of two CD-ROMs produced by the Space Telescope Science Institute through its Catalogs and Surveys Branch.

ESA announcement of a recalculation of the data which improves accuracy by compensating for systematic errors of thermal and micrometeoritic origin.