List of unnumbered minor planets


Breakdown of 963,399 small bodies of the Solar System:

The following is a list of unnumbered minor planets in chronological order of their principal provisional designation. Contrary to their numbered counterparts, unnumbered minor planets have a poorly determined orbit due to insufficient observational data. This also includes lost minor planets which have not been observed for many years, or even decades., the Minor Planet Center accounts for 413,149 unnumbered minor planets which represent of the overall minor planet population. Unnumbered minor planets can be further divided into 98,031 single-opposition objects with short observation arcs, prone to mismatch and loss, and 315,294 objects that have been observed multiple times during opposition, when astrometric conditions are most favorable. The JPL Small-Body Database gives a running total of 412,889 unnumbered minor planets.
The tables below contain 115 objects with a principal designation assigned between 1927 and 1993. Additional [|partial lists] cover the period from [|1994 to 2004]. Unnumbered minor planets detected after 2004 are not listed due to their large number . The orbital uncertainty parameter ranges from low to very high. For some single-opposition objects no numeric uncertainty is given, latter indicating an estimated, rather than determined orbital eccentricity. Furthermore, a color code is used to indicate a body's basic dynamical classification, with additional information given in columns "class" and "description and notes". If available, mean diameters are taken from the latest NEOWISE publication, or, if not available, estimated based on an object's absolute magnitude and displayed in italics.
In the Minor Planet Circular from July 2018, the MPC announced that changes in their data processing pipeline will enable numberings to occur more frequently. It is stated that the new method will clear the backlog of unnumbered minor planets with an already well-established orbit without changing the criteria for numbering. Previously, this was not possible because of the difficulty of determining who was the discoverer. Despite this announcement, however, the total of unnumbered minor planets has since rather than decreased.

Statistics

1900–1959

1960–1969

1970–1979

1980–1989

1990–1993

1994–2004

; 2001
; 2002
; 2003
; 2004
The year of principal provisional designation for most unnumbered minor planets is younger than 2004. They are not listed in any of the partial lists due to their large number and frequent changes. New partial lists may be created in the future, as additional observations ultimately lead to new numberings and to fewer unnumbered bodies.