Apollo astronauts and engineers tell the inside story of Apollo 8, the first manned mission to the moon. The U.S. space program suffered a bitter setback when Apollo 1 ended in a deadly fire during a pre-launch run-through. In disarray, and threatened by the prospect of a Soviet Union victory in the space race, NASA decided upon a radical and risky change of plan: turn Apollo 8 from an earth-orbit mission into a daring sprint to the moon while relying on untried new technologies. Fifty years after the historic mission, the Apollo 8 astronauts and engineers recount the feats of engineering that paved the way to the moon.
Neil deGrasse Tyson sets off on the Ship of the Imagination to chase a single comet through its million-year plunge toward Sol. Later, Tyson visits the birth-place of Sir Isaac Newton and retraces the unlikely friendship between Newton and brilliant polymath Edmond Halley. It was Halley's patience and generosity which allowed Newton to conquer his fear of isolation and find the courage to publish his masterwork, "Principia Mathematica" which launched a scientific revolution.
Venus is a gorgeous naked-eye planet, hanging like a diamond in the twilight -- but it’s beauty is best looked at from afar. Even though Mercury is closer to the sun, Venus is the hottest planet in the solar system, due to a runaway greenhouse effect, and has the most volcanic activity in the solar system. Its north and south poles were flipped, causing it to rotate backwards and making for very strange days on this beautiful but inhospitable world.
The Earth, the sun, the stars, and everything we can see, only comprise five percent of the universe. But what about the other 95 percent? Scientists are puzzling over dark matter and dark energy, the mysterious components that make up the rest.
Today Phil helps keep you from ticking off an astronomer in your life by making sure you know the difference between a meteor, meteorite, and meteoroid. When the Earth plows through the stream emitted by a comet we get a meteor shower. Meteors burn up about 100 km above the Earth, but some survive to hit the ground. Most of these meteorites are rocky, some are metallic, and a few are a mix of the two. Very big meteorites can be a very big problem, but there are plans in the works to prevent us from going the way of the dinosaurs.