Zepps asked deGrasse Tyson to respond to comments from another recent HuffPost Live guest, pastor Joel Osteen and who talked about his faith and science.

"I don't debate people's belief systems," deGrasse Tyson said. "What I will say is that kind of thing should not be in the science classroom because it's not science...If you [allow religion in the science classroom] you are undermining what science is and how it works."