The final episode of The Cosmos was kind of a bitter sweet warning to humanity. Sagan tells the story of how the Spanish conquistadors interacted with the Aztecs and how poorly that went. He then compares our current efforts of space exploration to those of the Spanish and implores us to take pity on any civilizations we may encounter. The episode ends with an overview of the previous twelve and a quote by Sagan that I found to be the highlight of the entire series. He said we need to cherish life and to continue our journey through the cosmos.

This episode was once again focused on the possibility of extraterrestrial life. However it used a more empirical approach than previous episodes did. It described our current efforts in through SETI and radio telescopes like the Arecibo Observatory. They use this data in the Drake equation and are able to determine what probability of life is present. Sagan does address some of the more hysterical claims of extraterrestrial life like ufo sightings but overall this episode described our big picture efforts.

This episode delves deeper into the idea of what constitutes intelligence. It starts by looking at a variety of things that can be considered intelligence including computers, people, and whales. Each of the things mentioned were all explained to have a base unit of communicating information with computer using bits, people using DNA, and whales using their songs. This episode brought up a very interesting idea in the Voyager golden record where we decided to place inscription on the voyager probe in the hopes that if an alien civilization every came across it they could understand that it was the result of intelligent life.

This episode was all about how the universe evolved. Sagan starts by explaining the big bang and how we should think of it not as an explosion but more like a rapid expansion of matter and how nothing existed before the big bang. He then explained how some strange occurrences in the solar system form, like quasars and galactic collisions. He then delved into how the universe as a whole might be structured, with the leading theory being that galaxies are clustered along strands of higher concentrations of dark matter.

This episode focused on stellar evolution. It started by describing the conditions that must be present for stars to form: cold dense gas. Then it went on to talk about the components that every star has and their life cycle. He then described the many ways that starts can end their lives. With low mass stars forming white dwarfs after going planetary nebula, and how high mass stars end their lives as type II supernova resulting in either a neutron star or a black hole.

This episode was focused on constellations and how the universe changes overtime as well as some of the phenomenon that we can observe. Sagan talked about red shifts and blue shifts and how they can tell us things about distant stars. He also talked about Einsteins theory of relativity and how one day we could have spacecraft that travel close to the speed of light. Overall this was one of my favorite episodes just because of how informative it was and how it covered a wide range of topics.

This episode was focused on the stories surrounding ancient astronomy and how often times astronomy was viewed as almost a religious practice. The episode was filmed in a classroom in Brooklyn New York where Carl Sagan was originally from. The most interesting part of the episode was when Sagan accurately predicted that astronomers would confirm the existence of exoplanets during those kids lifetimes.

This episode was all about the voyager space probes. The episode made the comparison of the probes exploration of our solar systems to the exploration of the Scandinavian vikings during the 1700’s. I thought it was really interesting how two probes could have discovered so much about the outer reaches of our solar system and it made me think about how much more we could discover if we put a larger emphasis on science. My favorite part of the episode was when they filmed Sagan receiving one of the first images of one of Jupiter’s moons.

This whole episode was dedicated to the planet mars. It gave a couple of description of the planet, one was from the novel The War of the Worlds, and the other was from the books Canals on Mars. It then described the viking projects and how they helped to discover a lot about the red planet. Then the episode ended by talking about tera-forming and possible colonization efforts.I thought the most interesting part of this episode was how in a hundred years we could have people who live on mars year round.

This episode was focused on the impacts of comets and asteroids as well as the greenhouse effects on Venus. I thought it was really interesting that humans have actually witnessed some of these impacts like in the Tunguska event. I had always thought that meteorite impacts were a prehistoric phenomenon so it surprised me that we have some written records of large meteor impacts. I also thought it was interesting that Venus used to be a lot like earth but it has experienced a runaway greenhouse effect. It is all the more reason to care about climate change.