Minor planet provisional designation in the context of "55565 Aya"

341520 Mors–Somnus (/ˌmɔːrs ˈsɒmnəs/; provisional designation 2007 TY₄₃₀) is a binary and plutino. It consists of two components less than 60 kilometers in diameter, orbiting at a distance of 21000 km.

Mors–Somnus was discovered on 14 October 2007, by American astronomers Scott Sheppard and Chad Trujillo with the Subaru Telescope at Mauna Kea Observatories in Hawaii, United States. It was later named after the twins Mors and Somnus from Roman mythology.

79360 Sila–Nunam (provisional designation 1997 CS₂₉) is a cold classical Kuiper belt object (cubewano) and binary system made up of components of almost equal size, called Sila and Nunam, orbiting beyond Neptune in the Solar System. The name of the system is the combined names of the two bodies, Sila and Nunam.

47171 Lempo, or as a binary (47171) Lempo–Hiisi (provisional designation 1999 TC₃₆), is a triple trans-Neptunian object in the Kuiper belt, located in the outermost regions of the Solar System. It was discovered on 1 October 1999, by American astronomers Eric Rubenstein and Louis-Gregory Strolger during an observing run at Kitt Peak National Observatory in Arizona, United States. Rubenstein was searching images taken by Strolger as part of their Nearby Galaxies Supernova Search project. It is classified as a plutino with a 2:3 mean-motion resonance with Neptune and is among the brighter TNOs. It reached perihelion in July 2015. This minor planet was named after Lempo from Finnish mythology.

The system's other two components, Paha /ˈpɑːhɑː/ and Hiisi /ˈhiːsi/, were discovered in 2001 and 2007, respectively, and later named after Lempo's two demon cohorts, Paha and Hiisi.

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. 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. The JPL Small-Body Database gives a running total of 676,786 unnumbered minor planets.

The tables below contain 115 objects with a principal designation assigned between 1927 and 1994. Additional partial lists cover the period from 1995 to 2004. Unnumbered minor planets detected after 2004 are not listed due to their large number. The orbital uncertainty parameter (U) ranges from low ("0") to very high ("9"). For some single-opposition objects no numeric uncertainty is given ("–"), with "E" 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). 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.

31824 Elatus (/ˈɛlətəs/; provisional designation 1999 UG₅) is a very red centaur from the outer Solar System, approximately 48 kilometers (30 miles) in diameter. It was discovered on 29 October 1999, by astronomers of the Catalina Sky Survey at Mount Lemmon Observatory in Arizona, United States. The minor planet was named after Elatus, a centaur from Greek mythology.

65803 Didymos (provisional designation 1996 GT) is a sub-kilometer asteroid and binary system that is classified as a potentially hazardous asteroid and near-Earth object of the Apollo group. The asteroid was discovered in 1996 by the Spacewatch survey at Kitt Peak, and its small 160-meter minor-planet moon, named Dimorphos, was discovered in 2003. Due to its binary nature, the asteroid was then named Didymos, the Greek word for 'twin'.

Didymos's moon, Dimorphos, was the target of the DART mission to test the viability of asteroid impact avoidance by collision with a spacecraft, while the impact was witnessed by LICIACube, a flyby CubeSat component of the mission.

4337 Arecibo (prov. designation: 1985 GB) is a binary asteroid in the outer regions of the asteroid belt, approximately 24 kilometers (15 miles) in diameter. It was discovered on 14 April 1985, by American astronomer Edward Bowell at the Anderson Mesa Station near Flagstaff, Arizona, in the United States. It was named after the Arecibo Observatory in Puerto Rico. It has a relatively large minor-planet moon that was discovered in stellar occultation observations by David Gault and Peter Nosworthy in May 2021, distinguishing it as the first asteroid moon discovered and confirmed solely using the occultation method.

208996 Achlys (provisional designation 2003 AZ₈₄) is a large trans-Neptunian object orbiting the Sun in the Kuiper belt, a region of icy bodies beyond Neptune. It was discovered on 13 January 2003 by Chad Trujillo and Michael E. Brown at Palomar Observatory. Achlys has an elongated shape that is believed to be distorted by its rapid 6.8-hour rotation. Its diameter is estimated to be roughly 940 km (580 mi) across its equator to 490 km (300 mi) across its poles. After Pluto and Orcus, Achlys is the third largest member of the plutinos—a population of Kuiper belt objects following a 2:3 orbital resonance with Neptune, in which they complete two orbits for every three orbits completed by Neptune.

The surface of Achlys is dark gray and mostly composed of water ice. Observations of stellar occultations show that Achlys's surface bears a chasm or depression between 8 and 13 km (5.0 and 8.1 mi) deep, similar to those seen on Pluto and its moon Charon. Achlys has one known moon that is about 80 km (50 mi) in diameter. The mass and density of Achlys has not been measured, though predictions based on its shape and rotation suggest that it has a density lower than that of water ice.

15760 Albion (provisional designation 1992 QB₁) was the first trans-Neptunian object to be discovered after Pluto and Charon. Measuring about 108–167 kilometres in diameter, it was discovered in 1992 by David C. Jewitt and Jane X. Luu at the Mauna Kea Observatory, Hawaii. After the discovery, they dubbed the object "Smiley" and it was shortly hailed as the tenth planet by the press. It is a "cold" classical Kuiper belt object and gave rise to the name cubewano for this kind of object, after the QB1 portion of its designation. Decoding its provisional designation, "QB₁" reveals that it was the 27th object found in the second half of August of that year. As of January 2018, around 2,400 further objects have been found beyond Neptune, a majority of which are classical Kuiper belt objects. It was named after Albion from William Blake's mythology.

(101429) 1998 VF₃₁ (provisional designation 1998 VF₃₁) is a sub-kilometer asteroid that orbits near Mars's L₅ Lagrangian point, on average trailing 60° behind it. Its orbit is highly stable, and was originally thought to be spectroscopically similar to 5261 Eureka, suggesting they may both be primordial Martian asteroids.

Spectroscopic observations through 2007 indicate that it has a large proportion of metal and achondrites on its surface (either with or without a mesosiderite contribution); which could also indicate that the surface regolith has undergone space weathering. These observations also reveal differences in the spectra with 5261 Eureka, suggesting they may not be related to each other after all.

(612243) 2001 QR₃₂₂, prov. designation: 2001 QR₃₂₂, is a minor planet and the first Neptune trojan discovered, by American astronomer Marc Buie of the Deep Ecliptic Survey at Cerro Tololo Observatory in Chile on 21 August 2001. It orbits ahead of Neptune at its L₄ Lagrangian point and measures approximately 132 kilometers (82 miles) in diameter.

Other Neptune trojans have been discovered since. A study by American astronomers Scott Sheppard and Chad Trujillo from the Carnegie Institution suggests that Neptune could possibly have twenty times more trojans than Jupiter.

145452 Ritona (provisional designation 2005 RN₄₃) is a large trans-Neptunian object orbiting the Sun in the Kuiper belt. It was discovered on 10 September 2005 by astronomers Andrew Becker, Andrew Puckett and Jeremy Kubica at Apache Point Observatory in Sunspot, New Mexico. Ritona has a measured diameter of 679+55
−73 km, which is large enough that some astronomers consider it a possible dwarf planet.

Ritona has a dark and reddish surface made of water ice, carbon dioxide ice, carbon monoxide ice, and various organic compounds (tholins). Observations by the James Webb Space Telescope have shown that carbon dioxide ice is more abundant than water ice in Ritona's surface, which suggests that there is a thin layer of carbon dioxide ice covering Ritona's surface. Ritona is not known to have any natural satellites or moons, which means there is currently no way to measure its mass and density.

532037 Chiminigagua (provisional designation 2013 FY₂₇) is a large trans-Neptunian object in the scattered disc. It was discovered on 17 March 2013 by Scott Sheppard and Chad Trujillo at Cerro Tololo Observatory in Chile. Chiminigagua has a nominal diameter of about 740 km (460 mi), which is large enough that some astronomers consider it a possible dwarf planet. Chiminigagua has a moderately red color, which suggests it has an old, ice-poor surface that has been dulled by cosmic rays and micrometeoroid bombardment. It has one unnamed moon about 190 km (120 mi) in diameter, which is believed to have formed from a giant impact on Chiminigagua.

(84522) 2002 TC₃₀₂ (provisional designation 2002 TC₃₀₂) is a mid-sized trans-Neptunian object located in the outermost region of the Solar System. It was discovered on 9 October 2002, by American astronomers Mike Brown, Chad Trujillo and David Rabinowitz at the Palomar Observatory in California. The resonant trans-Neptunian object stays in a 2:5 resonance with Neptune. It has a reddish color, a rotation period of 56.1 hours and measures at least 500 kilometers (310 miles) in diameter.

(87269) 2000 OO₆₇ (provisional designation 2000 OO₆₇) is a trans-Neptunian object, approximately 64 kilometers (40 miles) in diameter, on a highly eccentric orbit in the outermost region of the Solar System. It was discovered by astronomers at the Chilean Cerro Tololo Inter-American Observatory on 29 July 2000.