Why was Pluto demoted to a Dwart Planet? What is required of a celestial object to be designated as a planet today? With more discoveries of Pluto-type objects beyond the orbit of Pluto, is it possible to have a new designation for such objects in the solar system? Name other discovered Pluto-type objects in our solar system, and discuss possible ways to group them. (They must have enough common characteristics that are different than other objects in the solar system you've learned about)..