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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