• Processing (Info)

  • Packed Provisional and Permanent Designations

    This document describes the packed forms for provisional and permanent designations.

    Provisional Designations

    The provisional designation stored on the orbit and observations is stored in a 7-character packed format that saves space and makes sorting easier.

    Minor Planets

    A description of the format of provisional designations is available.

    The first two digits of the year are packed into a single character in column 1 (I = 18, J = 19, K = 20). Columns 2-3 contain the last two digits of the year. Column 4 contains the half-month letter and column 7 contains the second letter. The cycle count (the number of times that the second letter has cycled through the alphabet) is coded in columns 5-6, using a letter in column 5 when the cycle count is larger than 99. The uppercase letters are used, followed by the lowercase letters.

    Where possible, the cycle count should be displayed as a subscript when the designation is written out in unpacked format.

       J95X00A = 1995 XA
       J95X01L = 1995 XL1
       J95F13B = 1995 FB13
       J98SA8Q = 1998 SQ108
       J98SC7V = 1998 SV127
       J98SG2S = 1998 SS162
       K99AJ3Z = 2099 AZ193
       K08Aa0A = 2008 AA360
       K07Tf8A = 2007 TA418
    Survey designations of the form 2040 P-L, 3138 T-1, 1010 T-2 and 4101 T-3 are packed differently. Columns 1-3 contain the code indicating the survey and columns 4-7 contain the number within the survey.
       2040 P-L  = PLS2040
       3138 T-1  = T1S3138
       1010 T-2  = T2S1010
       4101 T-3  = T3S4101


    Columns 1-4 are as detailed above for minor planets. Columns 5-6 contain the order within the half-month period. Column 7 will normally be '0', except for split comets, when the fragment designation is stored there as a lower-case letter.
       1995 A1    = J95A010
       1994 P1-B  = J94P01b   refers to fragment B of 1994 P1
       1994 P1    = J94P010   refers to the whole comet 1994 P1
       2048 X13   = K48X130
       2033 L89-C = K33L89c
       2088 A103  = K88AA30   A3 = 103
    Comet designations may also be given in a 12-character form, where columns 6-12 are as described above. Column 5 will contain a `C', `P', `D' or `X' (depending on the status and orbit type of the comet). For a numbered periodic comet, columns 1-4 contain the periodic-comet number, left-padded with zeroes. For other comets columns 1-4 contain blanks.

    Natural Satellites

    The packed provisional format for satellite designations is identical to the packed format for comet designations, with the restriction that the last column (either column 7 or 12, depending on the form) always contains "0".

    Permanent Designations

    The permanent designation stored on the orbit and observations is stored in a 5-character packed format that saves space and makes sorting easier.

    Minor Planets

    If the minor-planet number is less than 100000, then the number is stored as a zero-padded right-justified string. E.g., (3202) is stored as "03202", (50000) as "50000".

    When the number is above 99999, the number MOD 10000 is stored in columns 2-5 of the string and the number DIV 10000 is represented by the letters A-Z (if between 10 and 35, inclusive) or a-z (if between 36 and 61, inclusive). E.g., (100345) is represented as "A0345", (360017) as "a0017", and (203289) as "K3289".


    Permanent designations for comets are only given to periodic comets seen to return (or for Centaur comets, seen at multiple apparitions). The comet number is stored zero-padded right-justified in columns 1-4. Column 5 usually contains "P", except for lost or defunct periodic comets when it contains "D".

    Natural Satellites

    Permanent designations for natural satellites are the Roman numerals. A permanent natural-satellite packed designation starts with a letter indicating to which planet the satellite belongs ("J" = Jupiter, "S" = Saturn, "U" = Uranus, "N" = Neptune), followed by a three-character zero-padded right-justified string containing the numerical representation of the Roman numeral, followed by "S". E.g., Jupiter XIII is represented as "J013S", Saturn X as "S010S" and Neptune II as "N002S".