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The Sky This Week

a weekly set of pictures and descriptions of the sky, stars, and planets.

Astronomical Applications


  • Optical/IR Products

    Optical/infrared image and catalog products provided by the USNO.  Astrometric catalogs include NOMAD, UCAC, USNO-B1, etc.  Imaging products include digital scans of a number of the major Schmidt telescope surveys of the skies, along with the catalogs of astronomical objects created from those images.  

  • VLBI-based Products

    Very Long Baseline Interferometry (VLBI) is a technique used by radio astronomers and geodesists to determine the celestial and terrestrial reference frames and to predict the variable orientation of the Earth in three-dimensional space.

  • Astrometry Information Center

    Your one-stop-source for astrometry related information.



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