Stephen Colbert

What does the demotion of Pluto really mean to Americans? Brian Williams, Stephen Colbert, Diane Sawyer, and Jon Stewart speculate.

If Pluto is not a planet, what is it? Diane Sawyer, Jon Stewart, Stephen Colbert, and Brian Williams try to explain.

Stephen Colbert tries to come up with a new mnemonic to remember the planets in preparation for NOVA's The Pluto FIles.

Stephen Colbert, Diane Sawyer, Brian Williams, and Jon Stewart wonder just who Neil deGrasse Tyson thinks he is?

A discussion about science, society, and the universe with Stephen Colbert, who is out of character, at the Kimberley Academy in Montclair, New Jersey.