The debate over Pluto’s planetary status has been ongoing since its reclassification as a “dwarf planet” in 2006 by the ...

On Aug. 24, 2006, the International Astronomical Union (IAU) decided that Pluto wasn't a planet anymore. Instead, Pluto is ...

Today in the history of astronomy, our solar system's ninth member is downgraded to a dwarf planet.

According to the IAU, a dwarf planet is as related to a planet as an asteroid is -- not at all. This hard definition has been drawing criticism since the IAU demoted Pluto in a 9-8 vote in 2006.

Pluto was demoted from a planet to a dwarf planet in 2006. So why is its status still so controversial today?

In Roman mythology, Pluto is the god and ruler of the dead. For a return mission to the dwarf planet, Howett and her ...

On the 95th anniversary of its discovery, Pluto remains one of the most beloved and enigmatic worlds in our solar system, whether you call it a planet or not.

“For that reason alone, Pluto’s status as a full-fledged planet should be kept.” Tombaugh came to NMSU in 1955 and developed a world-class astronomy research program.

The science community may be ecstatic over the discovery of a ninth planet, but the former planet "Pluto" had a totally different reaction.

Gingerich, despite being the former head of the same committee that voted on Pluto's demotion, argued that Pluto was in fact a planet at the Harvard-Smithsonian debate.