Minor Planet Center Annex



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Yearly Summaries

Updated: Friday, 13-Jan-2023 22:07:35 EST

Observations and Discoveries per Year

Source: ObsD.csv -- This is number observations and discoveries per given year processed by the MPC (starting from 1975).

Plot of the number of observations and discoveries per given year.

Observatory Codes per Year

Source: ObsCodesYrs.csv -- This is number of observatory_codes per given year (starting from 1975). Usually the observatory_code uniquely identifies the location of the observatory.

Plot of the number of observatory_codes per given year.

Summary Report

Source: ObsReportD.csv

ObsReport.csv header:

Year Code #Obs #NumMP-obj #UnumMP-obj #Comet-obj #Sat-obj #NumMP-obs #UnumMP-obs #Comet-obs #Sat-obs #Disc


For a given year (2021, for example) and for a given observatory_code (F51, for instance), it provides the total number of observations (#Obs), the total number of discoveries (#Disc), and two big categories: itemized objects and itemized observations.

An object is a unique body (minor planet, comet, asteroid...). It could be multiple observations of the unique body. For example, for the year 2021 the F51 observatory_code had 100+ observations of the comet 7P.

Each itemized category (objects and observations) are divided by the same set of sub-categories:

  • NumMP - Numbered Minor Planets
  • UnumMP - Unnumbered Minor Planets
  • Comets - self-explained
  • Sat - Satellites