Trans-Neptunian asteroids (or asteroids of the Kuiper Belt) have orbits located 30 to 60 astronomical units from the Sun and are in resonance with the planet Neptune. We suspect more than 2914, of which only 521 are numbered at the present date (January 15, 2022). These objects are considered to be the last remnants of the formation of the solar system and are the source of some comets and Centaurs. We suspect that there are at least 100000 larger than 100km. The largest, Orcus and Quaoar, are more than 1000km in diameter.
These objects are particularly difficult to observe. Their visual magnitude from Earth is greater than 22 and their apparent motion is very slow (the orbital period around the Sun is of the order of several centuries). Their orbits are not yet sufficiently well known, many did not have a name or a serial number. One third of them are similar to Pluto: their motion is in resonance (3: 2) with Neptune (named the "plutinos").
| Distance from Sun
|Inclination|| Dates of
|(420356) Praamzius||2012 BX85||210||42.8/43.0||170||1°||2005|