[FreedomCalls]

The poll in our family was unanimous that Pluto was a planet.

Based on what?

[Ruth A.]

There is no firm definition of a planet, but the International Astronomical Union has ruled that Pluto meets the criteria. Generally, Pluto is considered a planet because it orbits the sun and is large enough that its own gravity gives it a circular shape.

This same reasoning, but not stated as elegantly.