Question

i was surprised to learn the dwarf planet pluto used to be considered a planet. what would have had to happen for pluto to remain categorized as a planet? pluto would need to have an atmosphere. pluto would need to clear the neighborhood of its orbit. pluto would need to have a larger moon. pluto would need to have water or ice.

Explanation:

According to the International Astronomical Union's definition of a planet, a planet must orbit the Sun, be spherical in shape due to its own gravity, and clear the neighborhood of its orbit. Pluto fails in the third - criterion. So for Pluto to remain categorized as a planet, it would need to clear the neighborhood of its orbit.

Answer:

Pluto would need to clear the neighborhood of its orbit.