Pluto's status has been a heated debate for decades with arguing over a dwarf planet classification. Here's what international standards say in 2023.

When did Pluto stop being a planet, and why? Pluto was always in a tough spot when it came to being a planet. Just 1,477 miles across, it's only one-fifth the diameter of Earth.

Though Pluto has formally been considered a dwarf planet for almost two decades, it still has many lessons left for planetary scientists — including hints about how the solar system formed.

Arizona Gov. Katie Hobbs signed a bill making Pluto the official state planet. It was discovered at an observatory in Arizona, but was downgraded to a dwarf planet in 2006.

Pluto, officially a dwarf planet, has surprising complexity on its surface. While certainly a world, not everyone agrees it is a planet.

The whole thing is a bit silly, writes Dave Eicher. Is Pluto a planet? It's still out there, an intriguing, distant body in our solar system.

In 2006, astronomers ‘demoted’ Pluto from a major planet in the solar system to a dwarf planet. But was Pluto snubbed? Our experts answer.