As we approach the end of Crash Course Astronomy, it’s time now to acknowledge that our Universe’s days are numbered. Stars will die out after a few trillion years, protons will decay and matter will dissolve after a thousand trillion trillion trillion years, black holes will evaporate after 10^92 years, and then all will be dark. But there is still hope that a new Universe will be born from it.
The Ship of the Imagination ventures on an epic voyage to the bottom of a dewdrop to explore the universe on the smallest scale and observe exotic life forms invisible to the naked eye. Then, host Neil deGrasse Tyson explains the neural network in our brains which determine our sense of smell and memory, and later, he travels deep beneath the surface of the Earth to discover the most mysterious particle we know.
Today we’re talking about our galactic neighborhood: The Milky Way. It’s a disk galaxy, a collection of dust, gas, and hundreds of billions of stars, with the Sun located about halfway out from the center. The disk has grand spiral patterns in it, formed by the traffic jams of stars and nebulae, where stars are born. The central region is shaped like a bar, and is mostly old, red stars. There’s also a halo surrounding us of old stars.
For many years our place in the universe was the subject of theologians and philosophers, not scientists, but in 1960 one man changed all that. Dr Frank Drake was one of the leading lights in the new science of radio astronomy when he did something that was not only revolutionary, but could have cost him his career. Working at the National Radio Astronomy Observatory in Greenback in Virginia, he pointed one of their new 25-metre radio telescopes at a star called Tau Ceti twelve light years from earth, hoping for signs of extraterrestrial intelligence.
More than three decades after the debut of Carl Sagan's ground-breaking and iconic series, "Cosmos: A Personal Voyage," it's time once again to set sail for the stars. Host and astrophysicist Neil deGrasse Tyson sets off on the Ship of the Imagination to discover Earth's Cosmic Address and its coordinates in space and time. Viewers meet Renaissance Italy's Giordano Bruno, who had an epiphany about the infinite expanse of the universe. Then, Tyson walks across the Cosmic Calendar, on which all of time has been compressed into a year-at-a-glance calendar, from the Big Bang to the moment humans first make their appearance on the planet.