The probe’s revelations have revived debate about Pluto’s status ... concept that Earth and the other planets were few and special, instead of a better classification that would have ...

Long ago, in the pre-iPhone dark ages of 2006, Pluto was rebranded from its status as a planet and downgraded to dwarf planet classification, changing high school physics class forever.

Fifteen years ago, Pluto was kicked out of the planet club ... for a broader definition. The debate over classifying solar system objects reminds me of another classification challenge ...

I blame the Pluto people for that. (This is what a debate among astronomers talking about the term ‘dwarf planets’ was like.) Philip Metzger: We would say that there are a lot of dwarf planets ...

The decision to reinstate Pluto as a planet is not a recent topic of debate, however. There has been much argument over the classification of a planet since the ruling was made by the IAU.

Ever since Pluto lost its standing as a planet in 2006, people have been ­fighting to get it back. Last month, a debate among three experts had some interesting results. Dimitar Sasselov ...

But it's a classification that ... who presented the IAU definition at the Harvard debate. "In my world, Pluto is not a planet." A dwarf planet, according to the IAU definition, is not a type ...