Group U Dwarf Planets

Dwarf planets

Poor Pluto. Discarded from the solar system, and given the name a dwarf planet. However, it is a rather suitable name, considering the size of earth compared to Pluto, as shown here.


pluto, looked on by the side is about the size of australia.


The International Astronomical Union (IAU) currently has given the classification dwarf planets to Ceres, Pluto, Haumea, Makemake, and Eris. It is suspected that another hundred or so known objects in the Solar System are dwarf planets.

The only difference between a planet and a dwarf planet is the area surrounding each celestial body. A dwarf planet has not cleared the area around its orbit, while a planet has.
An easier definition might be that both planets and dwarf planets must orbit the Sun and be massive enough for their gravity to have pulled them into spherical or nearly spherical shapes.


Rather like asteroids or comets, plutos orbit is not neatly spherical, therefore giving it the dwarf planet name.

Another reason why is that it depends on whether it has “cleared the neighborhood around its orbit.” An object with a mass great enough for its strong gravity to have swept up or deflected away most of the smaller nearby bodies is considered a planet. An object that has failed to do so, and thus failed to grow larger, is a dwarf planet. pluto is one such.

Definition of body: a celestial body is any natural 'body' outside of the Earth's atmosphere. Easy examples are the Moon, Sun, and the other planets of our solar system. But those are very limited examples. The Kuiper belt contains many celestial bodies. Any asteroid in space is a celestial body.

all dwarf planets so far:

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