Pluto is probably best known for being a demoted planet. In 2006, the International Astronomical Union stripped it of its ...

According to a recent YouGov poll, 35% of Americans think Pluto is not a planet. But they are all wrong—kind of. To get to ...

In August 2006, the International Astronomical Union made the controversial, but correct, decision to demote Pluto from its ...

Pluto failed the third criterion. Unlike the eight recognized planets, Pluto shares its orbit with many other objects in the Kuiper Belt, meaning it has not "cleared its neighbourhood." ...

The other four moons ... in the solar system compared with its parent body. In fact, Charon and Pluto are so similar in size that they are considered a double dwarf planet system, not a planet ...

The number of planets that orbit the sun depends on what you mean by “planet,” and that’s not so easy to define ...

So things stood for 65 years. Although Pluto's orbit was more elongated than the other planets' (and even crossed the orbit of Neptune—not the kind of thing you would expect a decent planet to ...

Based on the predictions from Lowell and other astronomers ... to as a 'double planet'." Pluto's days, though they drag on a bit at around 153 hours, are nothing compared to its years.

Viewed in this longer context, the previously modern idea of having nine planets, which came about in the 1960s and lasted only until 2006, was a blip on the screen. And if you are still a Pluto ...

It's a lot of objects like Eris, like Pluto, like these other dwarf planets that are all the leftover chunks from the early solar system. It is really far away right now, but it comes in almost as ...

Ever since NASA's New Horizons sent back the first-ever photos of Pluto in 2015, the dwarf planet's mysterious heart ... which could apply to other Kuiper Belt objects as well.” ...