Carl Sagan examines our planet's place in the universe by leading us on a journey from Earth to Deep Space. Carl Sagan opens the program with a description of the cosmos and a "Spaceship of the Imagination" (shaped like a dandelion seed).

Image credit: PBS

The ship journeys through the universe's hundred billion galaxies, the Local Group, the Andromeda Galaxy, the Milky Way, the Orion Nebula, our Solar System, and finally the planet Earth. Eratosthenes' successful calculation of the circumference of Earth leads to a description of the ancient Library of Alexandria. Finally, the "Ages of Science" are described, before pulling back to the full span of the Cosmic Calendar. Note: the revised version of the series adds a two-minute introduction by Ann Druyan to this episode, in which she discusses some of the changes that occurred in the years after its broadcast.

YouTube video of Cosmos 1 by agarthas888