The Astrophysics Data System (ADS) is a gateway to over 13 million physics journal articles, preprints, conference proceedings, and books, one of the most comprehensive open science resources available to physicists world-wide. The digital library designed for NASA science indexes Physical Review ABCDEFMPRSX, Physica ABCD, Journal of Physics ABCDEFG CS, Physics Letters AB, Nuclear Physics AB, Journal of High Energy Physics, and more refereed journals plus non-refereed publications. In ADS, physicists can build complex queries of author, affiliation, title, keyword, or other metadata to find scholarly literature, data sets, and software. Links to the publisher’s version of record and open access versions increases access for all physicists. ADS visualizations map connections among authors and concepts, so physicists can pinpoint collaborations, influential works, and emerging trends quickly. Advanced ADS functions suggest review articles, trending papers, and similar research, essential for following rapidly evolving areas. Citation metrics and bibliographic tools allow physicists to track their impact and identify key papers. Custom libraries exported from ADS help physicists draft articles, grant proposals, and literature reviews. NASA directed ADS to cover planetary science, heliophysics, and earth science comprehensively. Therefore, ADS is expanding into a multidisciplinary search platform, the Science Explorer (SciX), which reveals commonalities across the physical sciences.