[[caption-width-right:330:"If you wish to make an apple pie from scratch, you must first ''[[MundaneMadeAwesome invent the Universe]]''."]]

-> ''"It does not harm the romance of a sunset to know a little bit about it."''

Carl Sagan (November 9, 1934 -- December 20, 1996) was [[Website/SFDebris a famous speaker of the word "billions"]] as well as an astronomer, astrophysicist, astrobiologist, philosopher, and author who through his various books, including one screenplay which would become the film ''{{Film/Contact}}'', and the TV Series ''Series/CosmosAPersonalVoyage'', became widely known as "The People's Scientist". Apart from his popularizations of science, he also contributed to research in the fields of planetary science, spacecraft exploration of the solar system, and the radio Search for Extraterrestrial Intelligence (SETI). He also developed theories on topics such as the nature of extraterrestrial lifeforms, the environmental effects of nuclear war (nuclear winter), and more.

In mainstream, he's somewhat of a star on Youtube; he's the centerpiece of the WebVideo/SymphonyOfScience videos, which auto-tunes Sagan's ''Cosmos'' along with other science programs to create [[strike:un]]expectedly awesome music videos, which total at about 8 million views. His ''[[TearJerker Pale]] [[CrowningMomentOfAwesome Blue]] [[CrowningMomentOfHeartwarming Dot]]'' speech is also a big hit, the two most watched versions having 1.7 Million views combined. His work, although the bulk of it was done 30+ years ago, still stands tall today within science, an incredible accomplishment.

Apart from his science-related work, he was also an activist to legalize marijuana, of which [[EruditeStoner he was a regular user]], and was very strongly opposed to the proliferation of nuclear weapons, even getting arrested in 1986 for interfering in a nuclear test. He was also a founder of the Committee for Scientific Investigation of Claims of the Paranormal ([[FunWithAcronyms CSICOP]]), which sought (and continues to seek, as the Committee for Skeptical Inquiry) to debunk most forms of paranormal and (later enlarged to) pseudoscientific claims (enlisting the assistance of Creator/IsaacAsimov and others, including Stephen Barrett who joined as a fellow later). He was thrice married, first to biologist Lynn Margulis, then to artist Linda Salzman, and finally to author Ann Druyan, with whom he co-wrote ''Cosmos'' and several of his books.

Fun Fact: His son Nick is a screenwriter who's done episodes of ''Series/StarTrekTheNextGeneration'' and ''Series/StarTrekVoyager''.

!Works he has been involved in include:

* ''Series/CosmosAPersonalVoyage'' (Co-writer, host)
* ''{{Literature/Contact}}'', both the novel and the [[{{Film/Contact}} movie]] (Writer)
* ''Music from a Small Planet'' (with Ann Druyan), a {{Radio}} documentary about the Voyager Interstellar Record. [[note]]A golden disc containing Earth music, voice messages and photographs, copies of which were launched into space on the Voyager 1 and 2 space probes on the off-chance that aliens would find them in interstellar space.[[/note]]
* ''Film/{{Threads}}'' (Scientific adviser)
* ''WebVideo/SymphonyOfScience'' (He's credited as artist on a released single)

!Books by Sagan include:

* ''The Dragons of Eden: Speculations of the Evolution of Human Intelligence'' - 1978
* ''Broca's Brain: Reflections on the Romance of Science'' - 1979
* ''Literature/{{Cosmos}}'' - Book form, 1980
* ''Comet'' - With Ann Druyan, 1985
* ''Literature/{{Contact}}'' - Book form, 1985
* ''Shadows of Forgotten Ancestors: A Search for Who We Are'' - With Ann Druyan, 1993
* ''Pale Blue Dot: A Vision of the Human Future in Space'' - 1994. Video excerpts are [[http://milkywaymusings.com/ pretty]] [[http://www.youtube.com/watch?v=wupToqz1e2g common]] [[http://www.youtube.com/watch?v=o9tDO3HK20Q online]].
* ''The Demon-Haunted World: Science as a Candle in the Dark'' - 1996
* ''Billions & Billions: Thoughts on Life and Death at the Brink of the Millennium'' - With Ann Druyan, 1997

!His major scientific contributions include:

* Providing research and evidence crucial to our modern-day knowledge of conditions on Venus.
* Initiating groundbreaking research on extraterrestrial life, including contributions to SETI ('''S'''earch for '''E'''xtra'''T'''errestrial '''I'''ntelligence).
* Contributing to the ''Galileo'' (Jupiter), ''Viking'' (Mars), ''Voyager'' (Outer Solar System), and ''Mariner'' (Venus) probe missions.
* Advocacy for humankind's expansion into space. Was one of the founders of The Planetary Society, a space advocacy group known for, among other things, its work on solar sail propulsion.
* Warning about the dangers of anthropogenic climate change and nuclear war.
* Over 400 books and journal articles in which he was a lead or co-author. Sagan [[{{Determinator}} continued working even as he was dying of bone cancer in 1996.]]

!!Tropes often invoked by Sagan include:

* ArcWords: Coined and repeatedly used some phrases, such as "technological adolescence", throughout his works.
* BeamMeUpScotty:
** "''B''illions and ''b''illions!" is one of Sagan's most oft-quoted terms, but he never actually said it that way. Sagan claimed he always pronounced "billions" with a strong, plosive B on the front so as to emphasize the fact that he wasn't just talking about mere millions. He also got rather annoyed when he did this at public speaking events and heard giggles from the audience. There's an awesome instance of Sagan {{Lampshading}} this trope and, in fact, {{subvert|edTrope}}ing it in the opening pages of his collection of essays titled ''Billions and Billions'':
---> I never said it. Honest. ... I said "billion" many times on the ''Series/{{Cosmos|APersonalVoyage}}'' television series, which was seen by a great many people. But I never said "billions and billions". [A page later.] For a while, out of childish pique, I wouldn't utter or write the phrase, even when asked to. But I've gotten over that. So, for the record, here goes: "Billions and billions."
** His possibly unique pronunciation of the word "cosmos" provoked lots of mirth in Great Britain, especially after impressionists and [[Radio/TheBurkissWay parodists]] got hold of it. For many people in Britain, ''Cosmos'' was their first introduction to the non-double-entendre pronunciation of the word "Uranus" - the dominant local pronunciation had always been "yoor-anus" - and the fact Sagan appeared to be conscientiously avoiding the "your arse" joke only served to lampshade it more. Kids in school playgrounds soon caught on to the weird alternative pronunciation and made a joke of it.
* CoolTeacher: Sagan tried to be this to the world, and for the most part he succeeded. More specifically, many of his own students are now celebrity scientists in their own right. (UsefulNotes/NeilDeGrasseTyson might be the best example.)
* DeadpanSnarker: From time to time.
-->We associate radio waves with intelligent life... or at least ''semi''-intelligent life; ''[[HumansAreMorons we]]'' have radio waves...
* EmotionalTorque: With regards to the real world, that too.
* EruditeStoner: Had toked many a joint in his lifetime. His wife Ann Druyan carries out his legacy as a popularizer of science and as president of the [=NORML=][[note]] National Organization for the Reform of Marijuana Laws[[/note]] Foundation Board of Directors.
** [[http://marijuana-uses.com/mr-x/ He actually wrote an article]] for ''Marihuana Reconsidered'' under a pseudonym.
* FirstContact
* GameOfNerds: PlayedWith. Sagan was a big sports fan in general (and sometimes used sports metaphors in his popularly-directed writing) and enjoyed playing basketball in his spare time.
* GentlemanAndAScholar: By all accounts, he was extremely gracious and courteous.
* HumansAreSpecial: In a certain sense.
* InsignificantLittleBluePlanet: Played with. On the one hand, he got a spacecraft, out almost 4 billion miles, to turn around and actually take a picture of the Earth as the eponymous Pale Blue Dot, and repeatedly argued that we shouldn't consider ourselves "privileged" or "special" over any other group of humans, or any other species, merely by birth. On the other hand, he spoke of humanity's potential to spread out into space and seek out its bearings in the cosmos, and that, while our homeworld Earth may be a tiny blue dot, it ''is'' the only place known to have evolved and sustained life, and there are no "better places", so far at least.
* LaymansTerms
* LargeHam: Sometimes comes across as this in his documentaries.
-->The planets of the galaxy might be FILLED with micro-organisms, but BIG beasts and vegetables and THINKING beings might be COMPARATIVELY RARE!
** This was most likely a case of Director's Revenge, an inverted form of ProtectionFromEditors, as there were difficulties between Sagan and the lead director on the set of ''Cosmos'', which manifested itself in the editing and blocking portraying Sagan as quite a bit more self-involved than he desired.[[note]]David Whitehouse's 1999 biography of Sagan discusses the situation in detail.[[/note]]
* MeasuringTheMarigolds: Also repeatedly debunked and strongly inverted.
* PatrickStewartSpeech: Several times, and eloquently delivered. May have even been the inspiration for the {{Trope Namer}}'s speeches in ''Series/StarTrekTheNextGeneration'', which aired 7 years after ''Cosmos''. Since his son had penned episodes for TNG, perhaps this penchant was InTheBlood?
* ReallyGetsAround: At least part of the reason why he ended up getting married three times.
* RomanticismVersusEnlightenment: Related to the above, a strong subversion. As indicated by the page quote, he believed that understanding the Universe (Enlightenment) did not detract from and even enhanced one's appreciation for nature (Romanticism).
* ScienceHero: Himself.
* SpaceIsAnOcean: Although the trope itself is averted, Sagan did make poetic analogies between the oceanic voyages in the Age of Exploration to the modern day exploration of the space - he called Earth the "shore of the cosmic ocean", and repeatedly referred to spacecraft, of all kinds - from small robotic probes like the Mariners and Voyagers, to grand hypothetical Bussard Ramjet interstellar designs - as "ships". Also, the Planetary Society's logo - a [[SpaceSailing sailing ship against the backdrop of a ringed planet]].
** The episode of Cosmos about the Voyager space probes ended with an image of the Voyager morphing into a wooden sailing ship.
* SpeculativeDocumentary
* TakeThat: Directed against Sagan by Apple Computer. Near the height of Sagan's popularity in the mid 1990s, Apple had three tiers of the new Power [=MacIntosh=] design they were working on, which would eventually be marketed as the 6100, 7100, and 8100. During development, as is common practice before the marketing names are settled upon, they had code names. The 6100 was "Cold Fusion," the 7100 was "Carl Sagan," and the 8100 was "Piltdown Man" -- in other words, Sagan's name was grouped together with a known scientific hoax and a suspected (at the time) scientific hoax. When Sagan complained, they changed the code name for the 7100 to "Butt-head astronomer." (Sagan later sued them for this second slight; the judge threw the case out, saying "One does not seriously attack the expertise of a scientist using the undefined phrase 'butt-head'.")
* VoiceClipSong: ''WebVideo/SymphonyOfScience''
* TheWorldIsJustAwesome: The former TropeNamer, through ''Literature/{{Contact}}''