List of unnumbered trans-Neptunian objects in the context of "Provisional designation in astronomy"

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⭐ Core Definition: List of unnumbered trans-Neptunian objects

This is a list of unnumbered trans-Neptunian objects (TNOs) first observed since 1993 and grouped by the year of principal provisional designation. The data is sourced from the Minor Planet Center's (MPC) List of Trans Neptunian Objects, List Of Centaurs and Scattered-Disk Objects, List Of Other Unusual Objects, and Database Search. These objects will eventually be numbered as secured discoveries with an official discoverer determined by the MPC. Until then, additional observations are needed to sufficiently decrease an object's orbital uncertainty. As of November 2025, there are 4,518 unnumbered objects, defined here as minor planets with a semi-major axis larger than 30.1 AU (Neptune's average orbital distance from the Sun).

The list also contains information from "Johnston's Archive", such as an object's diameter, its dynamical class and binary status with the satellite's diameter, as well as its albedo, spectral taxonomy and B–R color index. Members of the extreme trans-Neptunian objects (ESDOs, EDDOs and sednoids) – with a semi-major axis greater than 150 AU and perihelion greater than 30 AU – are also identified.

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List of unnumbered trans-Neptunian objects in the context of Trans-Neptunian object

A trans-Neptunian object (TNO), also written transneptunian object, is any minor planet in the Solar System that orbits the Sun at a greater average distance than Neptune, which has an orbital semi-major axis of 30.1 astronomical units (AU).

Typically, TNOs are further divided into the classical and resonant objects of the Kuiper belt, the scattered disc and detached objects with the sednoids being the most distant ones. As of February 2025, the catalog of minor planets contains 1006 numbered and more than 4000 unnumbered TNOs. However, nearly 5900 objects with semimajor axis over 30 AU are present in the MPC catalog, with 1009 being numbered.

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List of unnumbered trans-Neptunian objects in the context of List of trans-Neptunian objects

This is a list of trans-Neptunian objects (TNOs), which are minor planets in the Solar System that orbit the Sun at a greater distance on average than Neptune, which means all of their orbits have a semi-major axis greater than 30.1 astronomical units (AU). The Kuiper belt, scattered disk, and Oort cloud are three conventional divisions of this volume of space. As of October 2025, the catalog of minor planets contains 1,037 numbered TNOs. In addition, there are 4,518 unnumbered TNOs, which have been observed since 1993.

This list consists of all types of TNO subgroups: classical Kuiper belt objects, also known as "cubewanos", the resonant trans-Neptunian objects with their main and higher-order resonant subgroups, the scattered disc objects (SDOs), and the extreme trans-Neptunian objects including the ESDOs, EDDOs, and sednoids, which have a semi-major axis of at least 150 AU and a perihelion (closest approach to the Sun) greater than that of Neptune. The list also contains several centaurs, if the object's orbit has a sufficiently large semi-major axis (a). Centaurs have unstable orbits in which the perihelion (q) is well inside of Neptune's orbit but the farthest point (aphelion, Q) is very distant.

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