What are Pluto, Ceres, Eris, Haumea, and Makemake classified as?

Pluto, Ceres, Eris, Haumea, and Makemake are classified as dwarf planets. This classification is based on criteria established by the International Astronomical Union (IAU). According to these criteria, a dwarf planet is a celestial body that orbits the Sun, is not a satellite, has sufficient mass for its self-gravity to assume a nearly round shape, and has not cleared its neighboring region of other objects.

Pluto is often recognized as the most well-known dwarf planet, having been demoted from planet status in 2006. Ceres is particularly notable as the only dwarf planet located in the asteroid belt between Mars and Jupiter. Each of these celestial bodies shares similarities in their characteristics, which is why they are grouped under the category of dwarf planets. This classification emphasizes their unique status in the solar system compared to the larger, more massive planets, which have cleared their orbits of other debris.