# Cosmos: Possible Worlds
**Cosmos: Possible Worlds** is an American science documentary television series that premiered on March 9, 2020 on [National Geographic](https://www.edgepedia.org/national-geographic), hosted by astrophysicist [Neil deGrasse Tyson](https://www.edgepedia.org/neil-degrasse-tyson). It is the third series in the Cosmos franchise, following [Carl Sagan](https://www.edgepedia.org/carl-sagan)'s 1980 *Cosmos: A Personal Voyage* and the 2014 reboot *Cosmos: A Spacetime Odyssey*, and it explores lost worlds, worlds yet to come, and worlds humans may one day inhabit[1](https://www.rottentomatoes.com/tv/cosmos_possible_worlds) • [2](https://www.commonsensemedia.org/tv-reviews/cosmos-possible-worlds).
| Key fact | Detail |
|---|---|
| Premiere | March 9, 2020, National Geographic (later also broadcast on Fox)[1](https://www.rottentomatoes.com/tv/cosmos_possible_worlds) • [3](https://sciencemeetsfiction.com/2020/09/23/tv-review-cosmos-possible-worlds-week-1/) |
| Host | Neil deGrasse Tyson, returning from *Cosmos: A Spacetime Odyssey*[1](https://www.rottentomatoes.com/tv/cosmos_possible_worlds) |
| Writer / executive producers | Ann Druyan (writer and executive producer), with Seth MacFarlane, Brannon Braga, and Jason Clark as executive producers[1](https://www.rottentomatoes.com/tv/cosmos_possible_worlds) |
| Season 1 | 13 episodes; episode 8, "The Sacrifice of Cassini," aired March 30, 2020[4](https://www.rottentomatoes.com/tv/cosmos_possible_worlds/s01) |
| Critical reception | 80% Tomatometer (5 reviews) and 84% Popcornmeter on Rotten Tomatoes[1](https://www.rottentomatoes.com/tv/cosmos_possible_worlds) |
| Companion book | *Cosmos: Possible Worlds* by Ann Druyan, published in coordination with the series' international television debut[5](https://www.goodreads.com/book/show/55507996-cosmos-possible-worlds) |
| Content rating | Rated 10+ by Common Sense Media; no sex, language, or drinking content[2](https://www.commonsensemedia.org/tv-reviews/cosmos-possible-worlds) |
## Place in the Cosmos franchise
The series continues a lineage that began with *Cosmos: A Personal Voyage*, the 1980 PBS series hosted by Carl Sagan, which Common Sense Media calls a landmark of television science[2](https://www.commonsensemedia.org/tv-reviews/cosmos-possible-worlds). The 2014 reboot *Cosmos: A Spacetime Odyssey*, hosted by Tyson and produced with Sagan's widow [Ann Druyan](https://www.edgepedia.org/ann-druyan) and [Seth MacFarlane](https://www.edgepedia.org/seth-macfarlane), ran 13 episodes and closed on June 8, 2014[6](https://time.com/2853740/neil-degrasse-tyson-cosmos/). *Possible Worlds* uses the same production team and on-camera presenter as the 2014 series[7](https://natgeotv.com.au/cosmos-spacetime-odyssey-review/).
Druyan, Sagan's original creative collaborator, serves as the series' writer and executive producer[1](https://www.rottentomatoes.com/tv/cosmos_possible_worlds). Cosmos Studios, the production company behind the franchise, announced the new season by name while the first two Cosmos seasons were still airing[8](https://cosmosstudios.com/home/overview/).
## Content and themes
The show follows Tyson aboard the "Ship of the Imagination" on what Rotten Tomatoes' synopsis describes as a series of spiritual voyages of exploration, revealing previously uncharted realms including lost worlds, worlds yet to come, and worlds humans may one day inhabit[1](https://www.rottentomatoes.com/tv/cosmos_possible_worlds). Common Sense Media characterizes the series as exploring what humanity's future could look like if society focuses on scientific exploration and progress, grounded in current research-based theories, and highlights how present technology is being used to address human-created problems such as climate change[2](https://www.commonsensemedia.org/tv-reviews/cosmos-possible-worlds).
**Structure of the season.** The first episode, "Ladder to the Stars," asks where human civilization came from, revisiting the Cosmic Calendar, a device that maps the history of the universe onto a single year, before moving through early human art, the invention of the city, and the philosopher [Baruch Spinoza](https://www.edgepedia.org/baruch-spinoza)[3](https://sciencemeetsfiction.com/2020/09/23/tv-review-cosmos-possible-worlds-week-1/). Episode 2, "Shadows of Forgotten Ancestors," asks whether DNA is destiny, examining evolved behavior and the story of the Indian emperor Ashoka[3](https://sciencemeetsfiction.com/2020/09/23/tv-review-cosmos-possible-worlds-week-1/).
Later episodes cover the origin of life ("Lost City of Life"), the Russian botanist [Nikolai Vavilov](https://www.edgepedia.org/nikolai-vavilov) ("Vavilov"), the human brain ("The Cosmic Connectome"), a tribute to Carl Sagan and his mentors [Gerard Kuiper](https://www.edgepedia.org/gerard-kuiper) and Harold Urey ("The Man of a Trillion Worlds"), first contact with alien intelligence ("The Search for Intelligent Life on Earth"), and the Cassini-Huygens mission to Saturn ("The Sacrifice of Cassini")[9](https://sciencemeetsfiction.com/2021/02/04/tv-review-cosmos-possible-worlds/). The finale, "Seven Wonders of the New World," shows a vision of a better future at a 2039 World's Fair, one hundred years after the World's Fair that inspired Sagan's interest in science[9](https://sciencemeetsfiction.com/2021/02/04/tv-review-cosmos-possible-worlds/).
**"Vavilov" and biography.** Episode 4 tells the story of Nikolai Vavilov, who assembled the world's largest seed repository of his time while searching for the genetic origins of crops, and who died in a Soviet prison after a campaign against him by [Trofim Lysenko](https://www.edgepedia.org/trofim-lysenko)[9](https://sciencemeetsfiction.com/2021/02/04/tv-review-cosmos-possible-worlds/). A review at NatGeo TV Australia calls it the standout episode of the season, noting that Vavilov's colleagues starved during the siege of Leningrad rather than eat the seed collection[7](https://natgeotv.com.au/cosmos-spacetime-odyssey-review/). It is the only episode of any of the three Cosmos series titled with a person's name[9](https://sciencemeetsfiction.com/2021/02/04/tv-review-cosmos-possible-worlds/).
## Production and visual effects
[Visual effects](https://www.edgepedia.org/visual-effects) supervisor Jeffrey Okun, whose credits include *The Last Samurai*, *The Day the Earth Stood Still*, and *Clash of the Titans*, led the team depicting the cosmos on screen[10](https://www.televisionacademy.com/features/news/online-originals/journey-possible-worlds). He described the production as science-based, with access to astrophysicists and other scientists, and said his priorities were scientific accuracy first and beauty second[10](https://www.televisionacademy.com/features/news/online-originals/journey-possible-worlds). For the quantum physics episodes, Okun reported redoing one sequence from scratch seven complete times before arriving at something he considered roughly right[10](https://www.televisionacademy.com/features/news/online-originals/journey-possible-worlds). He also drew directly on Sagan's original series for inspiration, asking Druyan, "If Carl were with us right now, what do you think he'd let me do?"[10](https://www.televisionacademy.com/features/news/online-originals/journey-possible-worlds)
## Reception
On Rotten Tomatoes the series holds an 80% Tomatometer from 5 reviews and an 84% Popcornmeter audience score[1](https://www.rottentomatoes.com/tv/cosmos_possible_worlds). Steve Greene of IndieWire gave it an A, writing that its most valuable quality is the merging of "boundless optimism and the necessity of urgency"[11](https://www.metacritic.com/tv/cosmos-possible-worlds/critic-reviews/). Dave Trumbore of Collider rated it 4/5, calling it a necessary next step in science communication while citing a less-than-cohesive narrative, a lack of urgency, and Tyson's struggle to live up to Sagan's legacy[11](https://www.metacritic.com/tv/cosmos-possible-worlds/critic-reviews/). A more negative review from Glenn Garvin in Reason criticized the volume of CGI effects and the heavy use of Tyson[4](https://www.rottentomatoes.com/tv/cosmos_possible_worlds/s01).
The NatGeo TV Australia retrospective rated *Possible Worlds* the weakest of the three Cosmos series, judging the science solid but the pacing faster and more heavily produced than its predecessors[7](https://natgeotv.com.au/cosmos-spacetime-odyssey-review/).
## Broadcast and availability
The airing schedule shifted during the run: on Fox, episodes 10, 11, and 13 moved to Mondays while episode 12 stayed on Tuesday, and the Fox airing order corrected a swap made on National Geographic Channel between "Shadows of Forgotten Ancestors" and "The Fleeting Grace of the Habitable Zone"[9](https://sciencemeetsfiction.com/2021/02/04/tv-review-cosmos-possible-worlds/). Rotten Tomatoes lists a Season 2 trailer marked "Now in Production" alongside the series' one released season[1](https://www.rottentomatoes.com/tv/cosmos_possible_worlds).
## Companion book
Ann Druyan published a book of the same title in coordination with the series' international television debut. It travels through more than 14 billion years of cosmic evolution and into a projected future in which probes travel by light beams to distant stars[5](https://www.goodreads.com/book/show/55507996-cosmos-possible-worlds). The book's final chapter describes a hypothetical 2039 World's Fair whose futuristic vista is fashioned largely from materials derived from excess carbon dioxide pulled from the atmosphere[12](https://www.goodreads.com/book/show/53054359).
## References
1. [Cosmos: Possible Worlds, Rotten Tomatoes](https://www.rottentomatoes.com/tv/cosmos_possible_worlds)
2. [Cosmos: Possible Worlds, Parents' Guide & TV Review, Common Sense Media](https://www.commonsensemedia.org/tv-reviews/cosmos-possible-worlds)
3. [TV Review: Cosmos: Possible Worlds, Week 1, Science Meets Fiction](https://sciencemeetsfiction.com/2020/09/23/tv-review-cosmos-possible-worlds-week-1/)
4. [Cosmos: Possible Worlds: Season 1, Rotten Tomatoes](https://www.rottentomatoes.com/tv/cosmos_possible_worlds/s01)
5. [Cosmos Possible Worlds by Ann Druyan, Goodreads](https://www.goodreads.com/book/show/55507996-cosmos-possible-worlds)
6. [Neil deGrasse Tyson Looks Back at Cosmos, TIME](https://time.com/2853740/neil-degrasse-tyson-cosmos/)
7. [Cosmos: A Spacetime Odyssey Series Review, NatGeo TV Australia](https://natgeotv.com.au/cosmos-spacetime-odyssey-review/)
8. [Cosmos Studios, Overview](https://cosmosstudios.com/home/overview/)
9. [TV Review: Cosmos: Possible Worlds, Science Meets Fiction](https://sciencemeetsfiction.com/2021/02/04/tv-review-cosmos-possible-worlds/)
10. [Journey Into Possible Worlds, Television Academy](https://www.televisionacademy.com/features/news/online-originals/journey-possible-worlds)
11. [Cosmos: Possible Worlds critic reviews, Metacritic](https://www.metacritic.com/tv/cosmos-possible-worlds/critic-reviews/)
12. [Cosmos: Possible Worlds by Ann Druyan, Goodreads (first edition page)](https://www.goodreads.com/book/show/53054359)
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*Topic: Encyclopedia › Arts and culture › Screen and stage › Film and television › Series and fictional screen worlds › Unscripted, reality, and web-native series › Documentary, docudrama, and lifestyle series › Nature, wildlife, and science documentary series*
*Initially written Sep 17, 2026 · Reviewed: Oct 25, 2026 · Edited: Oct 15, 2026; Oct 25, 2026 · Last review: Oct 25, 2026*
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License: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license