A group of German astronomers organized themselves into a Missing Planet ... Mars and Pluto), not even the meanest of teachers would require students to learn all their names.

As the gatekeepers to the Kuiper Belt, Charon and Pluto are a unique double dwarf planet system. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it ...

And it's all wrapped up in one beautiful blue planet. Stern is Principal Investigator of NASA's New Horizons, the first mission to explore Pluto, which it should reach in 2015. The reason that I ...

Aside from the solar system once again having nine planets—which it had before Pluto’s demotion in 2006—the discovery of a distant Earth-mass planet would have profound implications for ...