List of unnumbered minor planets

Unnumbered minor planets (single-opposition): 129,103 bodies (9.9%)Unnumbered minor planets (multiple-opposition): 547,652 bodies (42.0%)Numbered minor planets: 623,827 bodies (47.8%)Comets: 4,586 bodies (0.4%)
Breakdown of 1,304,970 small bodies of the Solar System:[1][a]
  129,103 single-opposition MPs
  547,652 multiple-opposition MPs
  623,827 numbered MPs
  4,586 comets

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. As of August 2023, the Minor Planet Center (MPC) accounts for 676,755 unnumbered minor planets which represent 52% of the overall minor planet population.[1][a] Unnumbered minor planets can be further divided into 129,103 single-opposition objects with short observation arcs, prone to mismatch and loss, and 547,652 objects that have been observed multiple times during opposition, when astrometric conditions are most favorable.[1] The JPL Small-Body Database gives a running total of 676,786 unnumbered minor planets.[2][a]

The tables below contain 95 objects with a principal designation assigned between 1927 and 1993. Additional partial lists cover the period from 1994 to 2004.[a] Unnumbered minor planets detected after 2004 are not listed due to their large number (see statistics). The orbital uncertainty parameter (U) ranges from low ("0") to very high ("9"). For some single-opposition objects no numeric uncertainty is given ("–" and "E"), 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" (especially for near-Earth objects, Jupiter trojans and distant objects).[1][3][4] If available, mean diameters are taken from the latest NEOWISE publication,[5] or, if not available, estimated based on an object's absolute magnitude and displayed in italics.[6]

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.[7] Despite this announcement, however, the total of unnumbered minor planets has since significantly increased rather than decreased.

Statistics

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10,000
20,000
30,000
40,000
50,000
60,000
70,000
1995
2000
2005
2010
2015
2020
Unnumbered minor planets (uMPs) by year of principal designation. As of 29 January 2022 the MPC's orbit database contains 558,491 uMPs. Objects observed on a single opposition (total of 111,001) are displayed with a lighter color than multi-opposition objects (total of 447,490).[1][a]
  Until 2004: 31,553 uMPs (6%) are listed on this and other partial pages
  Since 2005: 526,935 uMPs (94%) are not listed

1900–1979

[edit]
U Designation Class Physical Observations Description and notes Ref
H D Opp. Arc Last Used
1927 LA MBA-O 11.0 35 km single 34 days 05 Jul 1927 3 Disc.: Heidelberg Obs.
Oldest lost asteroid
MPC · JPL
E 1935 UZ MCA single 4 days 23 Oct 1935 3 Disc.: Uccle Obs. MPC · JPL
1937 CK MBA-I single 32 days 13 Mar 1937 3 Disc.: Uccle Obs. MPC · JPL
1939 RR MBA-O 12.0 22 km single 27 days 12 Oct 1939 3 Disc.: Uccle Obs. MPC · JPL
1942 RH MBA-I 13.8 5.2 km single 10 days 15 Sep 1942 3 Disc.: Turku Obs. MPC · JPL
0 4847 P-L MBA-I 18.04 730 m multiple 1960-2022 25 Jan 2022 37 Disc.: Palomar–Leiden MPC · JPL
0 6331 P-L MBA-I 18.5 590 m multiple 1960–2021 01 Dec 2021 86 Disc.: Palomar–Leiden MPC · JPL
1 6344 P-L APO 20.4 300 m multiple 1960–2021 04 Aug 2021 129 Disc.: Palomar–Leiden
Potentially hazardous object
MPC · JPL
1 1960 SB1 MCA 17.91 1.5 km multiple 1960-2022 22 Mar 2022 56 Disc.: Palomar Obs.
Alt.: 2017 CT1
MPC · JPL
0 1979 MW5 MBA-O 16.47 2.8 km multiple 1979-2024 21 Dec 2024 124 Disc.: Siding Spring
Alt.: 2011 HG10
MPC · JPL
9 1979 XB APO 18.6 680 m single 4 days 15 Dec 1979 16 Disc.: Siding Spring
Potentially hazardous object
MPC · JPL

1980–1989

[edit]
U Designation Class Physical Observations Description and notes Ref
H D Opp. Arc Last Used
0 1981 EN35 MBA-I 17.46 960 m multiple 1981–2023 19 Nov 2023 209 Disc.: Siding Spring
Alt.: 2014 FN21
MPC · JPL
0 1982 YA AMO 18.01 1 km multiple 1982–2017 03 Dec 2017 71 Disc.: Haute-Provence
NEO larger than 1 kilometer
Alt.: 2003 WE42
MPC · JPL
0 1983 QC MCA 18.83 600 m multiple 1983–2018 11 Mar 2018 42 Disc.: Palomar Obs. MPC · JPL
0 1984 QL1 MCA 15.81 3.9 km multiple 1984–2024 17 Mar 2024 176 Disc.: Palomar Obs.
MBA-O at JPL
Alt.: 2002 XP102, 2013 JS30
MPC · JPL
0 1986 JE HUN 18.65 550 m multiple 1986–2022 19 Feb 2022 107 Disc.: Spacewatch
Alt.: 2005 UU548
MPC · JPL
0 1986 NA AMO 19.85 380 m multiple 1986–2021 31 Oct 2021 88 Disc.: Palomar Obs.
Alt.: 2013 UU3
MPC · JPL
0 1988 NE AMO 19.25 500 m multiple 1988–2022 17 Sep 2022 95 Disc.: Palomar Obs. MPC · JPL
0 1988 PF1 MCA 16.7 2.5 km multiple 1988–2021 18 Jan 2021 331 Disc.: Palomar Obs.
Alt.: 2009 WD77
MPC · JPL
1988 RH9 MBA-M 11.1 25 km single 11 days 12 Sep 1988 15 Disc.: La Silla Obs. MPC · JPL
0 1989 AZ APO 19.4 410 m multiple 1989–2024 17 Dec 2024 418 Disc.: Palomar Obs. MPC · JPL
E 1989 FR MBA-O 13.5 11 km single 2 days 28 Mar 1989 6 Disc.: Kleť Obs. MPC · JPL

1990–1992

[edit]
U Designation Class Physical Observations Description and notes Ref
H D Opp. Arc Last Used
2 1990 HY6 MBA-O 17.75 1.6 km multiple 1990–2022 19 Nov 2022 42 Disc.: Siding Spring
Alt.: 2012 XV90
MPC · JPL
0 1990 SM24 = (720001) MBA-O 16.36 3.0 km multiple 1990–2024 03 May 2024 301 Disc.: La Silla Obs.
Alt.: 2008 GU14
MPC · JPL
8 1990 UN APO 23.5 71 m single 15 days 06 Nov 1990 22 Disc.: Spacewatch MPC · JPL
3 1991 BA APO 28.6 7 m single 0 day 18 Jan 1991 7 Disc.: Spacewatch MPC · JPL
0 1991 GK MCA 19.43 390 m multiple 1991–2020 27 May 2020 128 Disc.: Spacewatch
Alt.: 2020 BE6
MPC · JPL
0 1991 GO APO 20.1 340 m multiple 1991–2023 10 Jun 2023 94 Disc.: Kitami Obs.
Potentially hazardous object
Alt.: 1999 HC
MPC · JPL
7 1991 JR AMO 23.4 71 m single 11 days 19 May 1991 20 Disc.: Spacewatch MPC · JPL
0 1991 PN MBA-O 16.91 2.3 km multiple 1991–2023 08 Sep 2023 55 Disc.: Cerro Tololo Obs. MPC · JPL
0 1991 PW22 MBA-M 17.45 1.4 km multiple 1991–2023 15 Jun 2022 76 Disc.: La Silla Obs.
Alt.: 2010 CU110
MPC · JPL
2 1991 RN28 MBA-I 19.2 430 m multiple 1991–2018 15 Oct 2018 35 Disc.: Spacewatch MPC · JPL
7 1991 TT APO 26.0 22 m single 3 days 09 Oct 1991 8 Disc.: Spacewatch
AMO at MPC
MPC · JPL
6 1991 TU APO 28.4 7 m single 0 day 07 Oct 1991 4 Disc.: Spacewatch MPC · JPL
0 1991 TY10 MBA-M 17.1 1.6 km multiple 1991–2021 07 Apr 2021 128 Disc.: Spacewatch
Alt.: 2011 PM15
MPC · JPL
0 1991 TM16 MCA 17.36 1.4 km multiple 1991–2021 07 Feb 2021 83 Disc.: Palomar–DSS
Alt.: 2017 AB3
MPC · JPL
1991 VA APO 26.5 18 m single 8 days 09 Nov 1991 13 Disc.: Spacewatch MPC · JPL
E 1991 VD HUN 19.5 370 m single 2 days 06 Nov 1991 9 Disc.: Spacewatch MPC · JPL
0 1991 VG APO 28.3 8 m multiple 1991–2017 01 Jun 2017 66 Disc.: Spacewatch MPC · JPL
8 1991 XA APO 23.7 65 m single 12 days 15 Dec 1991 7 Disc.: Spacewatch MPC · JPL
1 1991 XB AMO 18.8 620 m multiple 1991–2011 24 Jul 2011 38 Disc.: Palomar Obs. MPC · JPL
7 1992 DU APO 25.3 31 m single 3 days 29 Feb 1992 11 Disc.: Spacewatch MPC · JPL
5 1992 JD APO 25.0 36 m single 6 days 09 May 1992 23 Disc.: Spacewatch
AMO at MPC
MPC · JPL
0 1992 SW MCA 19.93 300 m multiple 1992–2024 09 Aug 2024 55 Disc.: Spacewatch MPC · JPL
1992 SX MCA 20.0 300 m single 7 days 04 Oct 1992 14 Disc.: Spacewatch MPC · JPL
0 1992 SZ AMO 19.97 350 m multiple 1992–2024 02 Jun 2024 70 Disc.: Spacewatch MPC · JPL
0 1992 SN4 MBA-M 18.55 820 m multiple 1992–2022 27 Jan 2022 65 Disc.: Spacewatch MPC · JPL
0 1992 SC8 MBA-M 18.38 890 m multiple 1992–2021 30 Nov 2021 82 Disc.: Spacewatch
Alt.: 2017 WV33
MPC · JPL
1 1992 SW11 MBA-I 17.28 1.0 km multiple 1992–2023 20 Aug 2023 24 Disc.: Spacewatch MPC · JPL
0 1992 SB12 MBA-I 19.7 600 m multiple 1992–2024 11 Sep 2024 45 Disc.: Spacewatch
Alt.: 2017 SW186
MPC · JPL
E 1992 SZ17 MBA-M 13.8 7.3 km single 4 days 03 Oct 1992 6 Disc.: Palomar Obs. MPC · JPL
E 1992 TY1 MBA-O 12.8 15 km single 3 days 05 Oct 1992 5 Disc.: Kitt Peak Obs. MPC · JPL
1992 TZ1 MBA-I 15.5 2.4 km single 4 days 05 Oct 1992 5 Disc.: Kitt Peak Obs. MPC · JPL
1 1992 XA MBA-O 17.5 1.8 km multiple 1992–2018 13 Dec 2018 161 Disc.: Spacewatch
Alt.: 2005 UG242
MPC · JPL
4 1992 YD3 APO 26.4 19 m single 0 day 27 Dec 1992 12 Disc.: Spacewatch
AMO at MPC
MPC · JPL

1993

[edit]
U Designation Class Physical Observations Description and notes Ref
H D Opp. Arc Last Used
7 1993 BD3 AMO 26.2 20 m single 5 days 31 Jan 1993 14 Disc.: Spacewatch MPC · JPL
7 1993 BU3 AMO 21.17 210 m single 33 days 03 Mar 1993 18 Disc.: Spacewatch MPC · JPL
1 1993 BC10 MBA-M 18.58 800 m multiple 1993–2024 12 Aug 2024 58 Disc.: Spacewatch MPC · JPL
6 1993 DA ATE 26.4 19 m single 5 days 22 Feb 1993 18 Disc.: Spacewatch MPC · JPL
7 1993 FA1 APO 25.9 23 m single 3 days 31 Mar 1993 17 Disc.: Spacewatch
AMO at MPC
MPC · JPL
0 1993 FB85 MBA-M 17.6 1.3 km multiple 1993–2022 29 Oct 2022 64 Disc.: Spacewatch
Alt.: 2002 GO188
MPC · JPL
0 1993 FE85 = (720002) MBA-M 17.69 1.2 km multiple 1993–2022 29 Nov 2022 101 Disc.: Spacewatch MPC · JPL
0 1993 HC APO 20.77 250 m multiple 1993–2021 07 May 2021 58 Disc.: Spacewatch MPC · JPL
3 1993 HP1 APO 27.1 14 m single 0 day 27 Apr 1993 27 Disc.: Spacewatch MPC · JPL
1993 KA APO 26.0 22 m single 9 days 26 May 1993 21 Disc.: Spacewatch
AMO at MPC
MPC · JPL
9 1993 KA2 APO 29.0 6 m single 1 day 22 May 1993 14 Disc.: Spacewatch MPC · JPL
0 1993 ME1 MCA 16.89 1.8 km multiple 1993–2023 26 Jul 2023 244 Disc.: Palomar Obs. MPC · JPL
1993 OT MCA 19.0 470 m single 20 days 13 Aug 1993 9 Disc.: Spacewatch MPC · JPL
0 1993 OM1 MBA-M 17.54 1.3 km multiple 1993–2023 24 Apr 2023 59 Disc.: Spacewatch
Alt.: 2015 MT193
MPC · JPL
0 1993 OW5 MBA-M 17.33 1.4 km multiple 1993–2022 28 Oct 2022 252 Disc.: La Silla Obs. MPC · JPL
0 1993 OP9 MBA-I 17.82 810 m multiple 1993–2022 24 Dec 2022 124 Disc.: La Silla Obs.
Alt.: 2004 TH237
MPC · JPL
1 1993 OY13 MBA-I 18.84 510 m multiple 1993–2022 19 Nov 2022 35 Disc.: Spacewatch MPC · JPL
0 1993 PA1 MBA-I 18.73 530 m multiple 1993–2023 13 Jan 2023 60 Disc.: Spacewatch
Alt.: 2009 QA32
MPC · JPL
0 1993 PK1 MBA-I 18.87 510 m multiple 1993–2023 22 Oct 2023 69 Disc.: Spacewatch MPC · JPL
3 1993 RP TNO 9.37 59 km multiple 1993-2016 02 Nov 2016 37 Disc.: Mauna Kea Obs.
LoUTNOs, res · 4:5
Alt.: 2015 VR202
MPC · JPL
0 1993 SZ16 = (720003) MBA-O 16.44 2.9 km multiple 1993–2023 23 Jan 2023 171 Disc.: Spacewatch MPC · JPL
1 1993 TZ APO 26.0 22 m multiple 1993–2016 14 Oct 2016 34 Disc.: Spacewatch MPC · JPL
1993 TR2 MCA 20.4 350 m single 12 days 24 Oct 1993 15 Disc.: Spacewatch MPC · JPL
0 1993 TK4 MBA-M 18.8 740 m multiple 1993–2023 03 Sep 2023 46 Disc.: Spacewatch
Alt.: 2019 SY43
MPC · JPL
0 1993 TQ4 MBA-I 18.06 730 m multiple 1993–2023 16 Apr 2023 45 Disc.: Spacewatch MPC · JPL
0 1993 TP6 MBA-I 19.2 430 m multiple 1993–2022 27 Nov 2022 79 Disc.: Spacewatch MPC · JPL
0 1993 TL8 = (720004) MBA-M 17.37 1.4 km multiple 1993–2021 07 Nov 2021 86 Disc.: Spacewatch
Alt.: 2012 UH179
MPC · JPL
0 1993 TC11 MBA-M 19.45 540 m multiple 1993–2022 29 Oct 2022 78 Disc.: Spacewatch MPC · JPL
0 1993 TC45 MBA-M 17.95 1.1 km multiple 1993–2023 13 Jan 2023 200 Disc.: La Silla Obs.
Alt.: 2007 BY108
MPC · JPL
6 1993 UA APO 25.4 30 m single 3 days 24 Oct 1993 15 Disc.: Spacewatch MPC · JPL
0 1993 UD AMO 20.38 300 m multiple 1993–2022 15 Dec 2022 68 Disc.: Spacewatch MPC · JPL
0 1993 UY7 MCA 18.75 530 m multiple 1993-2022 23 Oct 2022 52 Disc.: Spacewatch
Alt.: 2015 XV465
MPC · JPL
1 1993 VC MCA 20.5 330 m multiple 1993–2007 11 Nov 2007 34 Disc.: Spacewatch MPC · JPL
0 1993 VE6 MBA-I 19.16 440 m multiple 1993–2022 07 Apr 2022 49 Disc.: Spacewatch
Alt.: 2003 SE413
MPC · JPL

1994–2004

[edit]
2001
2002
2003
2004

2005–present

[edit]

The year of principal provisional designation for most unnumbered minor planets is younger than 2004 (see § Statistics). 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.

See also

[edit]

Notes

[edit]
  1. ^ a b c d e The data for this and other partial lists is sourced from the Minor Planet Center's orbit-database file (MPCORB.DAT). The number of entries typically differs from the summary figures published on the JPL and MPC web pages, as they may lag behind days, weeks, or even months. This includes MPC's "Latest Published Data" and "Archive Statistics – Orbits And Names".[8][9]

References

[edit]
  1. ^ a b c d e "Data Available from the Minor Planet Center – MPCORB.DAT". Minor Planet Center. 29 January 2022. (doc)
  2. ^ "How Many Solar System Bodies". Jet Propulsion Laboratory – Small-Body Database. Retrieved 14 August 2023.
  3. ^ "List Of Jupiter Trojans". Minor Planet Center. 26 January 2021.
  4. ^ Johnston, Wm. Robert (2 January 2022). "List of Known Trans-Neptunian Objects". Johnston's Archive. Retrieved 2 February 2022.
  5. ^ "NEOWISE Diameters and Albedos – V2.0". PDS Small Bodies Node. 2019.
  6. ^ "Asteroid Size Estimator". CNEOS NASA/JPL. Retrieved 13 May 2021.
  7. ^ "Minor Planet Circular (MPC 110641-111804) – Editorial Notice" (PDF). Minor Planet Center. 25 September 2018. Retrieved 22 February 2019.
  8. ^ "Latest Published Data". Minor Planet Center. 12 January 2022. Retrieved 14 August 2023.
  9. ^ "MPC Archive Statistics – Orbits And Names". Minor Planet Center. 18 May 2019. Retrieved 14 August 2023.