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Small Body Designation Formats

The following official designation formats are contained in the Small Bodies Database and recognized by the search utility:

Comet Designation Formats

New IAU Designation ("1994 V1", "1995 Q3", etc.)
A year followed by an upper-case letter indicating the half-month of discovery, followed by a number indicating the order of discovery. This may, in turn, be followed by a dash and another capital letter indicating one part of a fragmented comet.
Proper Name ("Shoemaker-Levy 9", "Halley", "Encke", ...)
An ASCII string of letters which may also include hyphens and single quotes.
Note that this is not case-sensitive and will match partial names anywhere within the comet name. So, for example, "iras" matches both "IRAS-Araki-Alcock" and "Hartley-IRAS".
The prefixes "P/" (periodic comet) or "D/" (defunct comet) may be used at the beginning of the search string to indicate that only that type of comet should be returned. When no prefix is included all types of comets will be listed.
Note: In order to have unique names for short-period (P < 200y) comets, the SBN will continue the previous IAU practice of putting sequential numbers after the name (e.g., "Shoemaker-Levy 9", "Tempel 1"). The SBN maintains a list of periodic comet names, with sequential numbers.
Periodic Comet Number ("1P", "2P", ... )
1-3 digits followed by an upper-case "P", indicating one of the multiple-apparition objects in the file. This is part of the new designation system.
Old IAU Provisional Designation ("1982i", "1887a", "1991a1" ...)
A year followed by a single lower-case letter, optionally followed by a single digit.
Old IAU Permanent Designation ("1378","1759 I", "1993 XIII", ...)
A year usually followed by a Roman numeral (which must be in upper-case) indicating the order of perihelion passage of the comet in that year. When there was only one comet passing perihelion in a year, then just the year number is used for this designation.

Note that the year must include all significant digits, i.e., "66" is interpreted as the year 66, not 1966. Years may be negative.

Asteroid Designation Formats

The IAU maintains a page describing the Naming of Astronomical Objects that includes how minor planets are named.

Asteroid Number
A sequential number assigned when an asteroid's orbit has become sufficiently well-determined. There are currently over 269,000 numbered asteroids.
Name ("Ceres", "A'Hearn", "Zappafrank", ...)
An ASCII string of letters which may also include hyphens and single quotes.
IAU Provisional Designation ("1989 SS2", "1998 HK33", "A869 GA", ...)
A four-digit year followed by a space, then two uppercase letters indicating the portion of the year of discovery, followed by an optional sequential number. This designation used an 'A' (for asteroid) in the century digit of the year number prior to 1924.
Asteroid Surveys ("2100 P-L", "1081 T-1", "1335 T-2", ...)
The Palomar-Leiden and Trojan survey identifications consist of a four-digit number followed by "P-L" or "T-1(2,3)", respectively.