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Astrometry Information Center

Within the astrometry information center you will find useful FAQs and information regarding the astrometric products delivered by USNO.

Catalog Information

Information regarding our merged and standalone astrometric catalogs including recommendations for catalog usage.

Double Star Information

Information regarding all components related to the Washington Double Star (WDS) catalog.

VLBI-based Product Information

Information related to VLBI products including Reference Frames (CRF/TRF), Earth Orientation Parameters (EOP), and the Radio Reference Frame Image Database (RRFID).


Publications relevant to our mission.

Astrometry Help Desk

Still have a question regarding one of our products?  Ask the astrometry help desk.

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