Pluto is no longer considered a regular planet by most of the scientific and astronomical community. It is now considered a Trans-Neptunian "dwarf planet."
{I kid you not.}
What most people do not realize, and what I did not know until fairly recently, is that just as Saturn has its rings, and just as there is an asteroid belt, so the Solar System, itself, is belted by a far larger ring system, the "remnants from the Solar System's formation," comprised primarily of methane, ammonia, and water.
They call this enormous ring of space matter the Kuiper Belt - named after famed San Francisco Giant's ballplayer and broadcaster Duane Kuiper - and Pluto is considered the largest object within the ring, itself.
Who knew?