Sign on

SAO/NASA ADS -> Help -> The ADS Data
SAO/NASA ADS Help Pages Prev | Next

    1.2 - About the Data in the ADS

    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 Service

    1.2.1 - Origin

    The abstracts database contains data from many different sources. The initial dataset was from NASA's Scientific and Technical Information group (STI) and covered the years 1975-1995. After that, we began collecting data directly from the journals as agreements were reached with them individually. In addition, we have collected references from SIMBAD, NED, conference editors, and individual authors. We have created electronic records from table of contents of most journals and conference series back to volume 1 as we have scanned them in order to provide complete bibliographic coverage.

    All bibliographic records include an Origin field which details where a given abstract came from. In cases where we have the same paper from multiple sources, we currently list them in the order above, but will soon merge the information into one complete record. It should be noted that we no longer receive data from STI, but that those abstracts in the system from STI are rewritten versions of the original author abstract. Our list of origins includes information on where some of our data come from.

    Click on our Journal Abbreviation List to see a full list of journals and their abbreviations.

    The full-text scans available in the ADS can be browsed through the ADS Browse Service. The scans were created by digitizing printed issues of astronomical publications. For more information on the full-text archive, please see the Scanned Literature help page.

    Many articles that are not scanned in the ADS may be ordered from the Center for Aerospace Information (CASI).

    Many of the dissertation citations contained in the ADS are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600 Web page:
    1.2.2 - Coverage

    The abstract databases contain records from hundreds of publications, colloquia, symposia, proceedings, and internal NASA reports. These sources cover diverse loosely astronomy-related subjects, ranging from Electrical Engineering through Optics to Particle Physics. They include the larger American astronomical journals: Astronomical Journal, Astrophysical Journal, Icarus, Publications of the Astronomical Society of the Pacific, etc, as well as many Non-American journals: Astronomy & Astrophysics, Monthly Notices of the Royal Astronomical Society, Publications of the Astronomical Societ of Japan / Australia / India, Astrophysical Journal of the Soviet Union / Australia / Ireland, etc., as well as more general interest journals such as Science, New Scientist, Nature, Mercury, Sky and Telescope, etc.. Complete coverage is only guaranteed for those journals we have scanned and placed online. That information is listed on our article service page.

    1.2.3 - Bibliographic Identifiers

    Creating unique Bibliographic codes (bibcodes from here on) allows us to identify literature in our database. Using a standard bibliographic format, as explained below, we can easily identify different bibliographic records and users can efficiently search for them.

    The bibliographic code is a 19 digit identifier which describes the journal article. The format was originally adopted by the SIMBAD and NED projects, and follows the syntax:



    • YYYY: Year of publication

    • JJJJJ: A standard abbreviation for the journal (e.g. ApJ, AJ, MNRAS, Sci, PASP, etc.). A list of abbreviations is available.

    • VVVV: The volume number (for a serial) or an abbreviation that specifies what type of publication it is (e.g. conf for conference proceedings, meet for Meeting proceedings, book for a book, coll for colloquium proceedings, proc for any other type of proceedings).

    • M: Qualifier for publication:
      E: Electronic Abstract (usually a counter, not a page number)
      L: Letter
      P: Pink page
      Q-Z: Unduplicating character for identical codes

    • PPPP: Page number. Note that for page numbers greater than 9999, the page number is continued in the m column.

    • A: The first letter of the last name of the first author.

    The fields are padded with periods (.) so that the code is always 19 characters long. The journal is left-justified within its 5 characters, and the volume and page are right-justified. New journal abbreviations should be unique, and follow existing naming conventions. As an example, the bibliographic code:


    corresponds to the article: Astrophysical Journal Letters volume 400, page L1.

    A list of journal abbreviations already in use is available on-line. Here are some abbreviations for the most popular Journals:
     ApJ:   Astrophysical Journal
     ApJS:  Astrophysical Journal Supplements
     ApJ:   Astrophysical Journal Letters (with an L in the Qualifier position).
     AJ:    Astronomical Journal
     A&A:   Astronomy & Astrophysics
     A&AS:  Astronomy & Astrophysics Supplements
     MNRAS: Monthly Notices of the Royal Astronomical Society
     PASP:  Publications of the Astronomical Society of the Pacific
     PASA:  Publications of the Astronomical Society of Australia
     PASAu: Proceedings of the Astronomical Society of Australia
     PASJ:  Publications of the Astronomical Society of Japan
    In order to accommodate conference proceedings and technical reports, the ADS has modified the original bibliographic code definition in order to present identifiers which are easily recognizable to the user. Conference proceedings, books, colloquia, workshops, and reports in the ADS typically contain a four letter word in the volume field such as conf, book, coll, work, or rept; all other type of proceedings use the identifier proc. For these bibliographic codes, the journal field typically consists of the first letter from important words in the title (e.g. for ''Information and On-Line Data in Astronomy'').

    Several oddities exist for bibcodes which do not fit into this paradigm. PhD theses, for example, contain a counter in lieu of a page number to distinguish between those written during the same year by authors whose surnames start with the same letter.

    Physical Review bibcodes began using an 6-digit id number in the late 1990's instead of a page number. For these articles, we have converted the first 2-digits of the id (which correspond to the issue number) into a lower-case letter in the 14th column. We then use the remaining 4 digits in the page number field.

    For conference abstracts submitted by the editors of a proceedings prior to publication, we often do not have page numbers. In this case, we use a counter in lieu of a page number and use an "E" (for Electronic) in the fourteenth column, the qualifier for publication. If these conference abstracts are then published, their bibliographic codes are replaced by a bibliographic code complete with page number. If the conference abstracts are published only on-line, they retain their electronic bibliographic code with its "E" and counter number.

    We have created two separate interfaces to assist our users and collaborators in searching and verifying the existence of records in our databases:

    • The Journal/Volume/Page form allows users to enter either a journal citation (in the top part of the form) or a bibcode (in the bottom part of the form). If a partial citation or bibcode is entered, all records matching the input data will be returned.

    • The bibcode verification utility is a simple interface allowing people to determine if a bibcode exists in the ADS.

    1.3 - Updates

    Updates to our databases are performed approximately every week, then mirrored to all of our mirror sites. Therefore, any new information added or change made to the databases does not become available immediately; rather it may take up to a week to become active. Corrections are always welcome, for example misspellings, missing pages/scans, broken links, etc. We also encourage you to submit original author abstracts to us through our Abstract Submission Form.

    1.4 - Acknowledgments

    We would like to thank the following publishers for their contributions and cooperation:

    • American Geophysical Union
    • American Institute of Physics
    • American Physical Society
    • Astronomical Society of the Pacific
    • Copernicus Publications
    • EDP Sciences
    • Elsevier Science
    • Institute of Physics Publishing
    • Lunar and Planetary Institute
    • Nature
    • Science
    • Springer
    • Wiley InterScience Publishers
    • World Scientific

    In addition we would like to thank the following organizations whose contributions enhance the value of our data:

    • ARI
    • CrossRef
    • JSTAGE
    • Proquest
    • SIMBAD
    • NASA STI
    • Wolbach Library

    We are grateful to many individuals who have contributed or are contributing metadata records and updates to the ADS. Among them:
          * Heinz Andernach, Universidad de Guanajuato, Mexico
          * Marsha Bishop, NRAO
          * Will Graves, CfA
          * Chris Erdmann, CfA
          * Sergei Grebenev, Space Research Institute, Moscow
          * Uta Grothkopf, ESO
          * Jill Lagerstrom, SCScI
          * Richard Mathar, Sterrewacht Universiteit Leiden 
          * Megan Nunemaker, NRAO
          * Wayne Osborn, Central Michigan University
          * Joe Tenn, Sonoma State University
          * Lance Utley, NRAO
    Additionally we thank those who have donated materials to be scanned.

Top | Next