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

GSC - The Online HST Guide Star Catalogue Visit

The Hipparcos Space Astrometry Mission -- European Space Agency's Hipparcos mission. Research tools, news, catalogues, education resources, and data. Visit

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

USNO PMM Star Catalogs -- 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 ten CD-ROMs) is also available provided you can provide a brief explanation of why USNO-SA2.0 isn't sufficient. That's information on over ½ a billion stars! Visit

The Hipparcos Catalogue Visit

White Dwarf Database -- An electronic database of the white dwarf stars. Visit

Catalog of White Dwarf Stars McCook & Sion -- A catalog of spectroscopically identified white dwarf stars, by George P. McCook & Edward M. Sion Visit

Astrometric holdings in ADC Archives -- Data sets in the Astronomical Data Center's Astrometric, & Positional data holdings. Contains site map, science data, news, and feedback. Visit

A New Reduction of the Hipparcos Catalogues -- ESA announcement of a recalculation of the data which improves accuracy by compensating for systematic errors of thermal & micrometeoritic origin. (September 27, 2007) Visit