It seems like we largely take it for granted these days, but the fact that we have humans living in space is the realization of a scientific dream a century old. Visit the space stations orbiting Earth past, present and future in this episode.
There are a number of theories for how the universe evolved but none are more widely accepted than the Big Bang theory. Learn about the mind-boggling details of the early universe and hear Dr. Neil deGrasse Tyson talk about what it will take for us to know its origins.
Since the Kepler telescope went online, astronomers have found there may be an estimate 40 billion planets like Earth in the Milky Way galaxy alone. What does it take for a planet to be considered Earth-like?