Some time after Pluto was “demoted” from planets to dwarf planets, the International Astronomical Union decided to sweeten this bitter pill for the poor man and introduced a new category of trans-Neptunian objects named after him.
Plutoids now included all dwarf planets orbiting the Sun in an orbit with a radius greater than the radius of the orbit of Neptune, which are in hydrostatic equilibrium and have not cleared the space around their orbit. At first, the honor of becoming plutoids was awarded to as many as two celestial bodies — Pluto itself and Eris. A little later, Makemake and Haumea joined them. Quavar, Sedna, and some other objects are candidates for plutoids.
Even with very large telescopes, Pluto is difficult to detect among the surrounding stars. Therefore, to observe this object, you need to choose zones with a minimum level of illumination and very powerful observation tools.