• MPC Preparation (Info)

  • MPEC Orbit Computers

    The following list, in initial-order, indicates the full names for the orbit computers that appear in abbreviated form on the Daily Orbit Update MPECs.
    Initial     Computer
       A        David Asher
       D        Andreas Doppler
       E        Edward Bowell
       I        Kiyotaka Ichikawa
       H        Carl Hergenrother
       K        Takao Kobayashi (before 2007)
       K        Sonia Keys
       M        Brian G. Marsden
       N        Syuichi Nakano
       R        Michael Rudenko
       S        Timothy B. Spahr (= X, before 2000 July 27)
       U        Takeshi Urata
       W        Gareth V. Williams
       X        Minor Planet Center staff or automated process
       Z        Joachim Schubart
       e        Maria Eugenia Sansaturio
       f        Giuseppe Forti
       g        Edwin Goffin
       i        Nina K. Sumzina
       n        Arno Gnadig
       r        Mike Kretlow
       s        Piero Sicoli (= S, before 2000 July 27)
    Additional names will be added to this list as necessary.

    Other codes

    In the column immediately preceding the orbit computer code, there may be a letter indicating that the orbit is e-assumed, that there is a double designation, or both.
    Code   Meaning
      D    Double designation (new double designations will
             be listed on the same MPEC)
      E    Eccentricity was assumed
      F    = D + E