• MPC Preparation (Info)

    • MPC: Publications

    Information is available on the following MPC publications:

    Minor Planet Circulars

    The Minor Planet Circulars (MPCs) (also known as Minor Planets and Comets) are published generally on the date of each full moon by the Minor Planet Center. The Circulars contain astrometric observations and orbits of both minor planets and comets. The astrometric observations of comets are published in full, while the minor-planet observations are summarised by observatory code (the full observations now being given in the Minor Planet Circulars Supplement). New numberings and namings of minor planets, as well as numberings of periodic comets, are announced in the Circulars. MPCs are also published in mini-batches, where there are no new numberings and there is no summary of minor-planet observations. Such mini-batches are usually published when there are staff unavailabilities around the time of publication. The observer, measurer and orbit computer details are referenced in the Astrophysical Data System.

    MPC publication began in 1947. ISSN 0736-6884.

    Minor Planet Circulars Supplement

    The Minor Planet Circulars Supplement contain the minor-planet observations, sorted by designation and date. It is these observations that are summarized in the MPCs. There is an MPS batch associated with each full batch of MPCs. In addition, there are the mid-month MPS batches, published at roughly weekly intervals, listing all the observations received in the previous week.

    MPS publication began in Oct. 1997. ISSN 1528-137X.

    Minor Planet Circulars Orbit Supplement

    The Minor Planet Circulars Orbit Supplement (MPOs) contain full details (including full residual blocks) on the orbits for newly-numbered, newly-linked and newly-identified minor planets. In addition, one-line orbits for one-opposition and previously-linked multi-opposition orbits are included: residual blocks for these orbits are not published but are available through the MPES.

    MPO publication began in May 2000. ISSN 2153-8530.

    Minor Planet Electronic Circulars

    The Minor Planet Electronic Circulars (MPECs) carry news on unusual minor planets and some routine material on comets. New discoveries of unusual minor planets (both near-Earth and trans-Neptunian objects) are announced via these circulars. Improved orbits appear frequently. Monthly lists of observable unusual objects, observable distant objects, observable comets and the critical list of numbered minor planets also appear on these circulars. Daily Orbit Update MPECs, issued every day, contain new identifications and orbits obtained over the previous 24 hours.

    Please note that the final publication of material that appears in the MPECs occurs in the MPCs. Material may appear on the MPECs that is subsequently corrected only in the MPCs: this behavior is consistent with the intent that the MPECs are to be treated as a temporary publication and the MPCs as a permanent publication.

    MPEC publication began in Sept. 1993. ISSN 1523-6714.

    Note on Printed Distribution of MPC Publications

    As a result of the 2009 Oct. free availability of MPC publications and services, the MPC can no longer provide printed copies of its publications. Full access to PDF versions of all MPC publications is available via the MPCArchive service, from which printed copies may be derived if desired.

    Discontinued Publications and Services

    The following services/publications are no longer available:
    • Extended Computer Service: the individual parts of the ECS are freely available from the main MPC page.
    • Computer Service
    • Catalogue of Orbits of Unnumbered Minor Planets.
    • Catalogue of High-Precision Orbits of Minor Planets (note minor change from earlier title Catalogue of High-Precision Orbits of Unnumbered Minor Planets).
    • The magnetic tape of observations.

    The Minor Planet Center no longer distributes the annual Efemeridy Malykh Planet (Ephemerides Of Minor Planets, EMP). Distribution of the EMP volume (and accompanying CD-ROM) is handled by the Institute of Applied Astronomy, Russian Academy of Sciences, Naberezhnaya Kutuzova 10, St. Petersburg, Russia.