The WORST episodes of Cosmos

Every episode of Cosmos ever, ranked from worst to best by thousands of votes from fans of the show. The worst episodes of Cosmos!

Carl Sagan brings us the Cosmos, everything that ever was and ever will be, in an approach that is easily accessible even for those of us that are not science wizards. This 13 part series covers everything from the history of astronomy, the challenges it faced at its creation, how the universe was created and how it all might end.First aired in 1980, updated segments have been added to the series to include recent discoveries and the current theories in astronomy.Winner of an Emmy and a Peabody Award.

Last Updated: 11/25/2024Network: PBSStatus: Ended
Blues for a Red Planet
star
8.29
345 votes

#1 - Blues for a Red Planet

Season 1 - Episode 5 - Aired 10/26/1980

Is there life on Mars? Dr. Sagan takes viewers on a tour of the red planet first through the eyes of science fiction authors, and then through the unblinking eyes of two Viking spacecrafts that have sent thousands of pictures of the stunning Martian landscape back to Earth since 1976. Though based on older Mars missions, Sagan's analysis still holds true.

Directors: Adrian Malone
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Encyclopaedia Galactica
star
8.37
380 votes

#2 - Encyclopaedia Galactica

Season 1 - Episode 12 - Aired 12/14/1980

Are there alien intelligences? How could we communicate with them? What about UFOs? The answers to these questions take us to Egypt to decode ancient hieroglyphics, to the largest radio telescope on Earth and, in the Spaceship of the Imagination, to visit other civilizations in space. Dr. Sagan answers questions such as: "What is the life span of a planetary civilization?" and "Will we one day hook up with a network of civilizations in the Milky Way galaxy?"

Directors: Adrian Malone
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The Shores of the Cosmic Ocean
star
8.47
857 votes

#3 - The Shores of the Cosmic Ocean

Season 1 - Episode 1 - Aired 9/28/1980

At the beginning of this cosmic journey across space and time, Dr. Carl Sagan takes us to the edge of the universe aboard a spaceship of the imagination. Through beautiful special effects, we witness quasars, exploding galaxies, star clusters, supernovas and pulsars. Returning to our solar system, we enter a re-creation of the Alexandrian Library, the seat of learning on Earth 2,000 years ago.

Directors: Adrian Malone
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Heaven and Hell
star
8.50
379 votes

#4 - Heaven and Hell

Season 1 - Episode 4 - Aired 10/19/1980

A descent through the hellish atmosphere of Venus to explore its broiling surface serves as a warning to our world about the possible consequences of the increasing greenhouse effect. Then Dr. Sagan leads us on a tour of our solar system to see how other heavenly bodies have suffered from various cosmic catastrophes.

Directors: Adrian Malone
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Travellers' Tales
star
8.51
301 votes

#5 - Travellers' Tales

Season 1 - Episode 6 - Aired 11/2/1980

Dr. Sagan compares the exhilaration of 17th-century Dutch explorers who ventured in sailing ships halfway around our planet in their quest for wealth and knowledge to an inside view of the excitement around Voyager's expeditions to Jupiter and Saturn. The newly acquired treasures of our present golden age of exploration are the focus of this episode.

Directors: Adrian Malone
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The Backbone of Night
star
8.55
324 votes

#6 - The Backbone of Night

Season 1 - Episode 7 - Aired 11/9/1980

Humans once thought the stars were campfires in the sky and the Milky Way "the backbone of night." In this fascinating segment Dr. Sagan takes us back to ancient Greece, when the basic question "what are the stars?" was first asked. He visits the Brooklyn elementary school of his childhood, where this same question is still on students' minds.

Directors: Adrian Malone
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One Voice in the Cosmic Fugue
star
8.55
573 votes

#7 - One Voice in the Cosmic Fugue

Season 1 - Episode 2 - Aired 10/5/1980

Dr. Sagan's cosmic calendar makes the history of the universe understandable and frames the origin of the Earth and the evolution of life. We see the evolutionary process unfold, from microbes to humans. Our understanding of how life developed on Earth enables us to venture to other worlds for imaginative speculations on what forms life might take elsewhere.

Directors: Adrian Malone
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The Lives of the Stars
star
8.58
421 votes

#8 - The Lives of the Stars

Season 1 - Episode 9 - Aired 11/23/1980

Using computer animation and amazing astronomical art, Dr. Sagan shows how stars are born, live, die and sometimes collapse to form neutron stars or black holes. We then journey into the future to witness "the last perfect day on Earth," 5 billion years from now, after which the sun will engulf our planet in the fires of its death throes.

Directors: Adrian Malone
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Harmony of the Worlds
star
8.66
518 votes

#9 - Harmony of the Worlds

Season 1 - Episode 3 - Aired 10/12/1980

This episode is a historical re-creation of the life of Johannes Kepler, the last scientific astrologer, the first modern astronomer and the author of the first science fiction novel. Kepler provided the insight into how the moon and the planets move in their orbits and ultimately how to journey to them. It's also a story about the scientific process of discovery, and how the search for truth is never easy but always worthwhile.

Directors: Adrian Malone
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Journeys in Space and Time
star
8.74
378 votes

#10 - Journeys in Space and Time

Season 1 - Episode 8 - Aired 11/16/1980

A voyage to see how star patterns change over millions of years is followed by a journey to the planets of other stars, and a look at the possibility of time travel. This takes us to Italy, where a young Albert Einstein first wondered what it would be like to ride on a beam of light.

Directors: Adrian Malone
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The Persistence of Memory
star
8.86
347 votes

#11 - The Persistence of Memory

Season 1 - Episode 11 - Aired 12/7/1980

The brain is the focus of this fascinating portion of our journey as Dr. Sagan examines another of the intelligent creatures with whom we share the planet Earth — whales. Then we wind through the maze of the human brain to witness the architecture of thought. We see how genes, brains and books store the information necessary for human survival.

Directors: Adrian Malone
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Who Speaks for Earth?
star
9.02
319 votes

#12 - Who Speaks for Earth?

Season 1 - Episode 13 - Aired 12/21/1980

Through the use of special effects we retrace the 15-billion-year journey from the big bang to the present. We also hear the tragic story of the martyrdom of Hypatia, the woman scientist of ancient Alexandria. This is the famous episode on nuclear war in which Dr. Sagan argues that our responsibility for survival is owed not just to ourselves, but also to the cosmos, ancient and vast, from which we spring.

Directors: Adrian Malone
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The Edge of Forever
star
9.13
332 votes

#13 - The Edge of Forever

Season 1 - Episode 10 - Aired 11/30/1980

Dr. Sagan leads us on some awesome trips — to a time when galaxies were beginning to form, to India to explore the infinite cycles of Hindu cosmology, and to show how humans of this century discovered the expanding universe and its origin in the big bang. He disappears down a black hole and reappears in New Mexico to show us an array of 17 telescopes probing the farthest reaches of space.

Directors: Adrian Malone
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