The NASA Science Explorer (SciX) is a digital library portal for researchers in astronomy, earth science, heliophysics, physics, and planetary science. The Smithsonian Astrophysical Observatory (SAO) operates SciX for the scientific community under a NASA cooperative agreement.

SciX is a multidisciplinary library based on the successful NASA Astrophysics Data Service (ADS) that has served astronomers and astrophysicists for more than a quarter century. Because ADS has increased the research efficiency of astronomers by at least 6%, NASA is expanding this valuable resource. By serving a broader range of disciplines, SciX will also foster interdisciplinary studies.

The four bibliographic collections maintained by SciX cover astronomy (including astrophysics, heliophysics, and planetary science), physics, earth science, and general science. Over all the system contains over 20 million records covering refereed publications plus all arXiv, ESS Open Archive, and EarthArXiv preprints. SciX has bibliographic records for 99% of the refereed literature in astrophysics, in part because of our longevity in the community; SciX earth science collection is continuously expanding, with the goal of 95% completeness by the end of 2024. Abstracts and full-text of publications are indexed and searchable through the new SciX search form as well as the legacy ADS search form.

In addition to its bibliographic corpus, SciX tracks citations and usage of its records to provide advanced discovery and evaluation capabilities. Integrated in its collections, SciX provides access and pointers to a wealth of external resources. Its rich web of links includes electronic articles available from publishers’ websites, preprints, astronomical object information, planetary features, data catalogs, and data sets hosted by external archives. SciX currently links to over 13.3 million records maintained by our collaborators. This depth of information has enabled multiple publications (refereed, non-refereed) in fields such as bibliometrics and information science.

As a critical component of NASA’s strategic initiative for open science, SciX empowers researchers to maximize their use of existing scientific knowledge. This rich global expertise is concentrated in the professional literature and associated information sources. Through SciX, scientists access these resources by direct, intelligent searches and by curated links between documents, software, and data. Multiple societies and individuals have recognized the unsurpassed role that ADS, the forerunner to SciX, has played in supporting the scientific community.

SciX is committed to the FAIR (Findable, Accessible, Interoperable, and Reusable) principles. Its advanced discovery tools enable researchers to Find relevant literature, refereed or non-refereed, along with associated software and data. Its records link to open source, preprint, and publisher’s versions of articles so that researchers can Access articles, current and historic. SciX is exploring machine learning techniques and collaborating with data archives to enrich the metadata associated with its records for both Interoperability and Reusability. Developed by scientists for scientists, SciX is continuously improving using open source code, models, and datasets.

Please note that SciX does not hold the copyright for the abstracts and articles, and their use is free for personal use only; open access abstracts and articles may have distinct terms. For more information, please read our page detailing the Terms and Conditions regulating the use of our resources.

If you wish to acknowledge SciX in a publication, please use a phrase such as: “This research has made use of NASA’s Science Explorer.”