Cosmos: A Space-Time Odyssey: Unafraid of the Dark Season 1, Ep 13
Victor Hess discovers cosmic rays, and Fritz Zwicky explains them. Tyson moves on to current questions in cosmology — just what are dark matter (also first proposed by Zwicky) and dark energy? The Voyager spacecraft are discussed, along with Sagan's role in designing the "golden record" they carry, and his suggestion that Voyager 1 take the "Pale Blue Dot" photograph of earth.
Cosmos: A Space-Time Odyssey: The World Set Free Season 1, Ep 12
Tyson shows the result of a runaway greenhouse effect on Venus. The earth has been getting warmer since the industrial revolution — but it's not too late.
Cosmos: A Space-Time Odyssey: The Immortals Season 1, Ep 11
On the possibility of life elsewhere in the universe. How meteorites may carry life between worlds, as well as allow earthly life to have survived the scouring of the earth's surface in its early history. The possibility and potential problems of communicating with intelligent extraterrestrial life. How civilizations die, and how ours may survive.
Cosmos: A Space-Time Odyssey: The Electric Boy Season 1, Ep 10
Michael Faraday, with little formal education, makes incredible discoveries regarding electromagnetism. [more inside]
We travel through Earth's past, glimpsing at how different the world used to be and learning what processes and events caused (and continue to cause) its changes. [more inside]