kääbusplaneeti

Kääbusplaneeti is the Finnish word for dwarf planet. A dwarf planet is a celestial body that orbits the Sun, is massive enough for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, but has not cleared the neighborhood around its orbit. It is also not a satellite of another planet. The International Astronomical Union (IAU) established this definition in 2006.

Currently, there are five officially recognized dwarf planets in our solar system: Ceres, Pluto, Haumea, Makemake, and Eris. Ceres is located in the asteroid belt between Mars and Jupiter, making it the only dwarf planet in the inner solar system. The other four dwarf planets are all located in the outer solar system, beyond Neptune, in a region known as the Kuiper Belt or the scattered disk. Pluto was reclassified from a planet to a dwarf planet in 2006 due to its failure to clear its orbital neighborhood.

The discovery of Eris in 2005, which is more massive than Pluto, was a significant factor in the IAU's decision to create the dwarf planet category. Scientists continue to search for more potential dwarf planets in the Kuiper Belt and beyond. Dwarf planets are distinct from planets because they share their orbital space with other objects of comparable size, whereas planets have gravitationally dominated their orbital regions.