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Reference Codes on Observations

Astrometric observations of comets, minor planets, and natural satellites accepted for publication in Minor Planet Circulars (MPCs), Minor Planet Supplements (MPSs), Minor Planet Electronic Circulars, and IAU Circulars receive a publication reference in columns 73-77 of the observation record.

Temporary References on MPECs

Observations appearing on MPECs receive temporary references that are later replaced by permanent ones when published in MPCs or MPSs.

Column Purpose
1 "E"
2 Half-month of MPEC preparation
3-5 Circular number within the half-month

Example: "MPEC 2004-P03" observations use reference EP003

Permanent References

Five-Digit References (MPC publication <= 99999)

Column Purpose
1-5 MPC number

Example: 24133 = MPC 24133

"@" + Four-Digit References (MPC > 99999)

Column Purpose
1 "@"
2-5 MPC number minus 100000

Example: @0133 = MPC 100133

"#" + Four Characters (MPC > 109999)

Column Purpose
1 "#"
2-5 Base-62 encoded (MPC number - 110000)

Uses characters 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz

Example: #002B = MPC 110135

Lower-case Letter + Four Digits (MPS publication)

Column Purpose
1 Encoded (MPS number รท 10000)
2-5 (MPS number) MOD 10000

Encoding: CHAR(97 + INT(MPS_Number / 10000)). "a" = MPS 1-9999, "b" = MPS 10000-19999, etc.

Examples: j8391 = MPS 98391, a0320 = MPS 320, k0001 = MPS 100001

Tilde + Four Base-62 Characters (MPS > 260000)

Column Purpose
1 "~"
2-5 Base-62 encoded (MPS number - 260000)

Examples: ~0000 = MPS 260000, ~007M = MPS 260456

Upper-case Letter + Four Digits (Various journals)

Column Purpose
1 Journal identifier
2-5 Circular number

Journal identifiers:

  • H = Harvard Announcement Card (HAC)
  • I = IAU Circular (IAUC)
  • M = Minor Planet Circulars (MPC)
  • R = Planetenzirkular des Astronomischen Rechen-Institut (RI)

Examples: R0034 = RI 34, I2340 = IAUC 2340

Two or More Letters (Non-MPC journals)

Journal identifiers range from two to five characters, often including volume or circular numbers.

ID Type Publication
AA V Astronomy and Astrophysics
AB C Bulletin des Astrophysikalischen Observatoriums Abastumani
AC C Astronomisches Zirkular der Akademie der Wissenschaften der UdSSR
AE V Astronomical Papers prepared for the use of the American Ephemeris and Nautical Almanac
AJ V Astronomical Journal
AN V Astronomische Nachrichten
AP V Astrophysical Journal Supplement
APO V Annales de l'Observatoire de Paris: Observations
AS V Acta Astronomica Sinica
AZ V Astronomicheskij Zhurnal
AcA V Acta Astronomica
As V Astronomy and Astrophysics Supplement
BA V Bulletin Astronomique
BB V Bulletin Astronomique de l'Observatoire Royal de Belgique, Uccle
BC V Bulletin of the Astronomical Institutes of Czechoslovakia
BG V Bulletin de l'Observatoire Astronomique de Beograd
BN I Bulletin of the Astronomical Institutes of the Netherlands
BP V Bulletin de la Societe des amis des sciences et des lettres de Poznan
BZ V Beobachtungs-Zirkulare der Astronomischen Nachrichten
CB I Comet Bulletin of the Orient Astronomical Association
CC V Observatorio Astronomico de Cordoba, Serie Contribuciones
CD I Tsirkulyari Rasadkhonai Stalinobod
CK V Izvestiya Krymskoj Astrofizicheskoj Observatorii
CM V Circulaire de l'Observatoire de Marseille
CMC V Carlsberg Meridian Circle Publications
CO V Odesskij Gosudarstvennyj Universitet Izvestiya Astronomicheskoj Observatorii
CR V Comptes Rendus hebdomadaires de l'academie des sciences de Paris
CS V Soobshcheniya Gosudarstvennogo Astronomicheskogo Instituta imeni P. K. Shternberga
GOxxx Y Greenwich Observations for the year 1xxx
HA V Harvard Annal
HD V Veroffentlichungen der Landessternwarte Heidelberg
HTCDR - Hipparcos-Tycho CD-ROM
IHW D International Halley Watch CD-ROM
Ic V Icarus
JB V Journal of the British Astronomical Association
JC C Japan Astronomical Study Association Circular
JO V Journal des Observateurs
KB V Bulletin of the Kwasan Observatory, Kyoto
KK C Kiev Komet Tsirkular
LB C Lick Observatory Bulletin
LO C Lowell Observatory Bulletin
LP V Publicaciones Observatorio Astronomico de La Plata
MN V Monthly Notices
NA V Annales de l'Observatoire de Nice
NC C Nihondaira Observatory Circular
NO V Publications of the U.S. Naval Observatory, Second Series
NZ C Nachrichtenblatt der Astronomischen Zentralstelle
OB V The Observatory
PA V Publications of the Astronomical Society of the Pacific
PC C Poulkovo Observatory Circular
PD V Tartu Astronoomia Observatooriumi Publikatsioonid
PK V Pyublikatsii Kievskoj Astronomicheskoj Observatorii
PO I Perth Observatory Communication
PP I Izvestiya Glavnoj Astronomicheskoj Observatorii v Pulkove
PT V Pubblicazioni del Osservatorio di Torino
PZ C Zirkular des Astronomischen Hauptobservatoriums Pulkowo
RA V Ricerche Astronomiche
RM V Memoirs of the Royal Astronomical Society
SA V Monthly Notices of the Astronomical Society of Southern Africa
SOB V Observatory Bulletin
TB V Tokyo Astronomical Bulletin
TC C Transval Observatory Circular
TI V Astronomia-Optika Institucio, Universitato de Turku, Informo
UC C Circular of the Union Observatory, Johannesburg
WO V Astronomical Observations of the U.S. Naval Observatory, Washington
WiA V Annalen der Sternwarte der Universitat Wien
pM V Mitteilungen der Nikolai-Hauptsternwarte zu Pulkowo

Type notation: V = volume numbers, C = circular numbers, I = issue number, D = CD-ROM numbers, Y = years

Examples: AN080 = AN 80, MN008 = MN 8