NASA Astrophysics Data System

The Astrophysics Data System (ADS) is a NASA- funded project which maintains three bibliographic databases containing more than 4.5 million records: Astronomy and Astrophysics, Physics, and ArXiv e-prints. The main body of data in the ADS consists of bibliographic records, which are searchable through our Abstract Service query forms, and full-text scans of much of the astronomical literature which can be browsed though our Browse interface. Integrated in its databases, the ADS provides access and pointers to a wealth of external resources, including electronic articles, data catalogs and archives. We currently have links to over 4.4 million records maintained by our collaborators. (Updated regularly)

Database Permalink

This permalink is a direct, persistent URL to the database that will always work and won't break.


19th century - present

License Info

Unlimited simultaneous users


Harvard-Smithsonian Center for Astrophysics, Computation Facility, and NASA


19th century - present

Resource Types

Article Database

Online Availability

View Online