In 2006, Pluto was famously demoted from a planet to a dwarf planet. It remains the most famous dwarf planet today, but there are others in our solar system, including potentially hundreds that ...

The reclassification of Pluto as a dwarf planet continues to stir up a hornet's nest of controversy and debate, as Space.com meets one astronomer who believes the decision to have been a mistake.

Add Yahoo as a preferred source to see more of our stories on Google. Beyond the familiar planets lies a fascinating frontier filled with icy worlds, mysterious orbits, and cosmic curiosities. These ...

Pluto lost its planethood for a very specific reason. Whether or not that’s a good reason depends on who you ask.

Those who supported Pluto’s demotion included Neil DeGrasse Tyson ...