Episode 4: "Heaven and Hell"
* 1. Opening
* 2. Heaven and Hell
* 3. Tunguska Event
The Tunguska event
* 4. Comets
The composition and origin of comets
* 5. Collisions with Earth
Asteroids and impact craters
Lunar impact seen by Canterbury monks in 1178 (Giordano Bruno (crater))
* 6. Planetary Evolution
* 7. Venus
The controversial theories of Immanuel Velikovsky
The planet Venus in fiction and fact
* 8. Descent to Venus
* 9. Change
Human impact on the global environment
* 10. Deaths of Worlds
Venus as an example of the greenhouse effect
* 11. Conclusion
* 12. Cosmos Update 10 years later
The hellish conditions of Venus are a reminder of increasing greenhouse effect.
Cosmos: A Personal Voyage is a thirteen-part television series written by Carl Sagan, Ann Druyan, and Steven Soter, with Sagan as global presenter. It was executive-produced by Adrian Malone, produced by David Kennard, Geoffrey Haines-Stiles and Gregory Andorfer, and directed by the producers and David Oyster, Richard Wells, Tom Weidlinger, and others. It covered a wide range of scientific subjects including the origin of life and a perspective of our place in the universe.
The series was first broadcast by the Public Broadcasting Service in 1980, and was the most widely watched series in the history of American public television until The Civil War (1990). It is still the most widely watched PBS series in the world. It won an Emmy and a Peabody Award and has since been broadcast in more than 60 countries and seen by over 600 million people, according to the Science Channel. A book to accompany the series was also published.
Episode 1: "The Shores of the Cosmic Ocean"
Episode 2: "One Voice in the Cosmic Fugue"
Episode 3: "The Harmony of the Worlds"
Episode 4: "Heaven and Hell"
Episode 5: "Blues for a Red Planet"
Episode 6: "Travellers' Tales"
Episode 7: "The Backbone of Night"
Episode 8: "Journeys in Space and Time"
Episode 9: "The Lives of the Stars"
Episode 10: "The Edge of Forever"
Episode 11: "The Persistence of Memory"
Episode 12: "Encyclopaedia Galactica"
Episode 13: "Who Speaks for Earth?"
Episode 14: "Ted Turner Interviews Dr. Sagan"
Cosmos was produced in 1978 and 1979 by Los Angeles PBS affiliate KCET on a roughly $6.3 million budget, with over $2 million additionally allocated to promotion. The show's format is based on previous BBC documentaries such as Kenneth Clark's Civilisation, Jacob Bronowski's The Ascent of Man and David Attenborough's Life on Earth. (The BBC—a co-producer of Cosmos—repaid the compliment by screening the series, but episodes were cut to fit 50-minute slots and shown late at night.) However, unlike those series, which were shot entirely on film, Cosmos used videotape for interior scenes and special effects, with film being used for exteriors.
The series is notable for its groundbreaking use of special effects, which allowed Sagan to apparently walk through environments that were actually models rather than full-sized sets. The soundtrack included pieces of music provided by Greek composer Vangelis such as Alpha, Pulstar, and Heaven and Hell Part 1 (the last movement serving as the signature theme music for the show, and is directly referenced by the title of episode 4). Throughout the 13 hours of the series it used many tracks from several 1970s albums such as Albedo 0.39, Spiral, Ignacio, Beaubourg, and China. The worldwide success of the documentary series also put Vangelis' music in the homes and to the attention of a global audience.
Turner Home Entertainment purchased Cosmos from series producer KCET in 1989. In making the move to commercial television, the hour-long episodes were edited down to shorter lengths, and Sagan shot new epilogues for several episodes in which he discussed new discoveries (and alternate viewpoints) that had arisen since the original broadcast. Additionally, a 14th episode was added which consisted of an interview between Sagan and Ted Turner, and this "new" version of the series was eventually released as a VHS box set.
Cosmos had long been unavailable after its initial release because of copyright issues with the included music, but was released in 2000 on worldwide NTSC DVD, which includes subtitles in seven languages, remastered 5.1 sound, as well as an alternate music and sound effects track. In 2005 The Science Channel rebroadcast the series for its 25th anniversary with updated computer graphics, film footage, and digital sound. Despite being shown again on the Science channel, the total amount of time for the original 13 episodes (780 minutes) was reduced 25% to 585 minutes (45 minutes per episode) in order to make room for commercials.
While Sagan was outspoken about political issues in this series and elsewhere, the popular perception of his characterization of large cosmic quantities was that of a sense of wonderment at the vastness of space and time. His famous saying at the start of Episode 8: Journeys in Space and Time "The total number of stars in the Universe is larger than all the grains of sand on all the beaches of the planet Earth" was widely misunderstood, as he was in fact referring to the world being at a "critical branch point in history where our actions will propagate down through the centuries". He stated at the end of Episode 8: Journeys in Space and Time
"Those worlds in space are as countless as all the grains of sand on all the beaches of the earth. Each of those worlds is as real as ours and every one of them is a succession of incidents, events, occurrences which influence its future. Countless worlds, numberless moments, an immensity of space and time. And our small planet at this moment, here we face a critical branch point in history. What we do with our world, right now, will propagate down through the centuries and powerfully affect the destiny of our descendants. It is well within our power to destroy our civilization and perhaps our species as well."