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Library of Congress

15 Highlights from Carl Sagan's Archive

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Library of Congress

Recently, the Library of Congress acquired and began to digitize The Seth MacFarlane Collection of the Carl Sagan and Ann Druyan Archive, a compilation of the personal papers, books, and correspondence of noted astrophysicist Carl Sagan. Through more than a dozen books, as well as his groundbreaking 1980 television series Cosmos: A Personal Voyage—soon to be remade in March featuring equally awesome astrophysicist Neil deGrasse Tyson—Sagan used his wondrous spirit to urge people to look at the planet and our place in the universe in different, dynamic ways. Here are a few awesome things we found in the collection.

1. Home Movies of a Young Sagan

The video above shows a series of silent home movies, starting off with the young Sagan joking around while playing piano. Other clips—with appearances by his mother Rachel, his father Samuel, and his younger sister Carol—show Sagan horseback riding, on vacation, and documenting a family trip to the zoo.

2. The Evolution of Interstellar Space Flight

This wonderful drawing was created by pre-teen Sagan, and is a collage of proposed newspaper headlines from the future. One headline boasts of technological developments like atomic space ships that can travel 5 miles per second, while another imagined advertisement promotes “Interstellar Spacelines," encouraging people to travel to and inhabit a planet in another solar system called "Altair 8."

3. Wawawhack, the Rahway High School student newspaper, Vol. VI, No. 5.

This issue of Wawawhack, the Rahway High School student newspaper, contains a student spotlight section describing Sagan's accomplishments as a high schooler. “If you wish to gain information concerning anything,” the article says, “go to Carl Sagan.” The short piece also describes his ambition to become an astronomer when he grows up, lists his hobbies as reading and playing basketball, labels his pet peeve as “lettuce sandwiches,” and names his favorite song—“My Foolish Heart, the title song from the film adaptation of the JD Salinger short story “Uncle Wiggly in Connecticut.”

4. The sounds of Earth

This is Sagan’s personal copy of the gold-plated copper record disc that NASA produced in 1977 to accompany the Voyager 1 & 2 spacecraft into interstellar space for potential alien civilizations to discover. The disc includes 115 images of Earth cultures, natural sounds, music, and spoken greetings in 55 languages. The phrase “To the makers of music—all worlds, all times” is etched around the center of both sides. Also found in the archive is a 1986 birthday greeting to Chuck Berry by Sagan and his eventual wife Ann Druyan (Berry’s song “Johnny B. Goode” was included on the record), and a thank-you letter to famed ethnomusicologist Alan Lomax for helping compile the music for the disc.

5. The Pale Blue Dot

Sagan dictated many of his science-related thoughts and much of his official correspondence. This 4-minute audio recording is the abstract for his 1994 book, Pale Blue Dot, and ponders the primary concepts gained from the famous “Pale Blue Dot” photo taken, at Sagan's request, more than 4 billion miles from earth by the Voyage 1 spacecraft in 1990. “Consider that dot,” said Sagan, “That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives.” The archive also includes the second of 20 drafts of Sagan’s book.

6. Diagram of all space and time

This diagram, drawn by Sagan in 1985, represents all of space and time. The X-axis illustrates past and future time, while the Y-axis illustrates scale from the minute size of electrons to the distance to the “M31” or Andromeda Galaxy. Note the relative size of the small box that represents the “Realm of Direct Human Experience” to the huge space given to the realms of Quantum Physics and Special Relativity, and also the ominously titled “Forbidden Zone.”

7. Jovian radio organisms

Throughout his later career, Sagan would keep a file composed of initial concepts for writing projects that piqued his interest that he called his “Ideas Riding” file—a play on the phrase “Ideas Writing.” In this one-page document, the astrophysicist contemplates the “very speculative idea” that large plantlike organisms on Jupiter could communicate using radio waves like “a vast sing-along or the noise leakage from an immense cocktail party.” Pretty trippy. Other documents from this file include everything from notes on the nature of the clouds on Venus to an observation about how whale songs sound like cello music to asking “why are clouds white?”

8. Briefing notes for President Carter and Vice President Walter Mondale

This handwritten note—on Watergate Hotel stationery—was used for a presentation by Sagan to brief then-President Jimmy Carter and Vice President Walter Mondale on concepts like the origin of life; the Voyager record; “cosmic catastrophes” like pulsars, quasars, and black holes; and CETI, or ”communication with extraterrestrial intelligence.”

9. Letter to Brown University Admissions Office

This college recommendation letter was written by Sagan and sent to the admissions office of Brown University, endorsing a student named David Grinspoon for admission to the school. Sagan declares that Grinspoon “would rank in the upper one percent of the students in my introductory astronomy course at Cornell,” and notes that the young student is an “accomplished tennis and guitar player.” Grinspoon would eventually attend Brown, and would even get a second recommendation letter from Sagan—also in the collection—when he was trying to get into graduate school at the University of Arizona. Additional correspondence between the two includes a letter Sagan wrote to the undergrad asking him to help him find an astronomy book written by sci-fi author H.P. Lovecraft.

10. Viking Lander images of the surface of Mars

These photographs are Sagan’s personal copies of the images sent back to earth from the Viking lander in 1977. Sagan was obsessed with the Red Planet, and the collection also includes a photo of Sagan with a model of the lander taken in Death Valley, California.

11. Idea for Contact video game

Sagan wasn’t content working in just literature, academia, or television. In this document, he chews over how to create a video game that could teach astronomy “in a context as exciting as most violent video games.” The premise of the video game would involve creating a young galactic civilization “in order to help it before it destroys itself—which most of them generally do.” Ever the optimist, Sagan also considered how the video game could be a tie-in to his novel Contact, which would be published in 1985. The collection also includes a dictated first draft of chapter three and a full draft of the novel.

12. Candidate list of Why? books

Sagan connected with so many people thanks to his knack for making audiences easily understand some pretty difficult scientific concepts. This list from later in his life contains about 150 potential titles for a series of instructional books for children called “Why?” Some examples include “How High is the Sky?”, “Why Don’t I Feel the Earth Spin?”, “If a Baby Was Raised by Mutes, What Language Would it Speak?”, “Could there be an Undiscovered Number Between 1 and 2?”, and “Why is it Warm in Summer?”

13. Scientists tithe time to science education

Anticipating the contemporary lack of funding and support for potentially costly scientific endeavors, Sagan proposed that scientists themselves should donate ten percent of their time towards public education in science. As a way for these scientists to contribute to a better public understanding of science, Sagan suggests they should write articles in local newspapers, give public lectures, and hold open houses at observatories.

14. Lecture notes

Though he was the most high profile astrophysicist of his time, Sagan was still a university professor with coursework, exams, and research papers to assign. The collection give us a little look into just what it might have been like to be enrolled in—or to teach—one of his classes.

One document for the “Astronomy 490” course he taught at Cornell in the '80s features lecture notes written by Sagan himself, which encourage students to push their critical thinking between “what feels good versus what is true,” and explains that the course will follow the logical idiom “Post hoc ergo propter hoc.” One of the course’s final exams features an essay question asking students to describe the ways culture may change in the years following a major event involving UFOs, while another asks students to create a thought experiment for or against sun sign astrology.

For his 1965 “Astronomy 170” course at Harvard, his lecture notes outline topics such as the possibility of life on Mars and his desire to spend class time contemplating Saturn’s rings.

15. Correspondence between Sagan and a young Neil deGrasse Tyson

Perhaps my favorite discovery in the collection is a series of correspondence between Sagan—who was at the height of his popularity—and a young Neil deGrasse Tyson, an astrophysicist who has now taken over Sagan’s mantle in bringing popular science to the masses.

The banter starts with a letter from Sagan to Tyson—who was a senior at The Bronx High School of Science at the time—inviting the young man to visit him at Cornell and praising his decision to major in physics. Following their meeting and some time later, Tyson responds to Sagan informing him he has decided to attend Harvard because they have a larger astronomy department, to which Sagan cheekily responds that he’s sure Tyson has “not made a serious error in going there rather than Cornell.”

The formal friendship gives way to casual communication when Tyson send Sagan a letter about his first year as an undergrad at Harvard, and how he sublet an apartment in Cambridge for the summer so he could work full time at the Center for Astrophysics until school started up again. The pièce de résistance is a letter Tyson sent Sagan asking him how he would go about finding a publisher for turning a series of Q&A articles he wrote into a full-length book. The message includes a newspaper clipping about Tyson to remind Sagan of his accomplishments. It also features Tyson wearing a particularly goofy, but great astronomy-themed t-shirt.

The digitized collection is only in the preliminary stages, and the entirety of the documents from Sagan’s estate numbers in the hundreds more. If you’re as much of a Sagan fan—or science geek—as I am, let’s hope they put them online sooner rather than later.

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Cotswold Archaeology
Stones, Bones, and Wrecks
Amateur Archaeologists in England Unearth Rare Roman Mosaic
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Cotswold Archaeology

For the past three years, amateur archaeologists and historians in southern England have been working side-by-side with volunteers to excavate several seemingly related local Roman sites. Now, just two weeks before the dig's scheduled conclusion, they've made a fantastic discovery: a rare 4th-century CE mosaic that is being hailed as "the most important of its type in Britain in more than half a century," according to The New York Times.

Dating to roughly 380 CE, the mosaic was unearthed near the village of Boxford in Berkshire. The project—which included a rotating assembly of 55 members—involved local interest groups like the Boxford History Project and the Berkshire Archaeological Research Group, and was overseen by Cotswold Archaeology, a company that helps builders preserve archaeological finds. Funding was provided by the Heritage Lottery Fund, which gives grants to heritage projects across the UK.

In the project's first two years, the group members discovered a large Roman villa, a bathhouse, and a farmstead. In 2017, they began excavating the main villa, a site that yielded pottery, jewelry, coins, and other ancient objects. None of these artifacts, however, were as spectacular as the mosaic, which volunteers unearthed in a moment of serendipity shortly before funding for the dig ended.

Revealed sections of the artwork depict scenes featuring Bellerophon, a mythological Greek hero, along with other fabled figures. Bellerophon is famous in legends for capturing the winged horse Pegasus and for defeating the Chimera, a fire-breathing creature with a lion's head, a goat's body, and a serpent's tail.

Citizen archaeologists in Boxford, England unearth a Roman mosaic thought to date from 380 CE.
Cotswold Archaeology

"The range and style of imagery is very rare in the UK, where simple geometric patterns are the norm," Duncan Coe, a principal heritage consultant with Cotswold Archaeology, tells Mental Floss. "The combination of artwork and inscriptions is unique in this country. The range of imagery is also unique, with at least two scenes from the story of Bellerophon, a character from Greek mythology, augmented by Hercules and the Centaur, Cupid and telamones [male statues used as a column]—and we only have half of the mosaic revealed so far."

Excavators uncovered nearly 20 feet of the mosaic, but ultimately reburied it to deter looters and prevent damage. Members of Boxford's local archaeological community hope to secure funding and return to the site—now dubbed the Boxford villa—to dig up the entire scene.

A Roman mosaic thought to date from 380 CE, unearthed by citizen archaeologists in Boxford England.
Cotswold Archaeology

In addition to teaching experts about the villa's owners—who were evidently sophisticated and wealthy—and Boxford's ancient heritage, the newly discovered mosaic isn't just any ordinary artwork, according to Coe: "This isn't just an isolated mosaic, but a small, but very important, part of a bigger jigsaw that advances our understanding of what was happening in southern England just before the Roman government abandoned Britain," he says.

[h/t The New York Times]

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Wikimedia Commons // Public Domain
15 Riveting Facts About Alan Turing
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Wikimedia Commons // Public Domain

More than six decades after his death, Alan Turing’s life remains a point of fascination, even for people who have no interest in his groundbreaking work in computer science. He has been the subject of a play and an opera, and referenced in multiple novels and numerous musical albums. The Benedict Cumberbatch film about his life, The Imitation Game, received eight Oscar nominations. But just who was he in real life? Here are 15 facts you should know about Alan Turing.


Turing essentially pioneered the idea of computer memory. In 1936, Turing published a seminal paper called “On Computable Numbers” [PDF], which The Washington Post has called “the founding document of the computer age.” In the philosophical article, he hypothesized that one day, we could build machines that could compute any problem that a human could, using 0s and 1s. Turing proposed single-task machines called Turing machines that would be capable of solving just one type of math problem, but a “universal computer” would be able to tackle any kind of problem thrown at it by storing instructional code in the computer’s memory. Turing’s ideas about memory storage and using a single machine to carry out all tasks laid the foundation for what would become the digital computer.

In 1945, while working for the UK’s National Physical Laboratory, he came up with the Automatic Computing Machine, the first digital computer with stored programs. Previous computers didn’t have electric memory storage, and had to be manually rewired to switch between different programs.


Turing began working at Bletchley Park, Britain’s secret headquarters for its codebreakers during World War II, in 1939. By one estimate, his work there may have cut the war short by up to two years. He’s credited with saving millions of lives.

Turing immediately got to work designing a codebreaking machine called the Bombe (an update of a previous Polish machine) with the help of his colleague Gordon Welchman. The Bombe shortened the steps required in decoding, and 200 of them were built for British use over the course of the war. They allowed codebreakers to decipher up to 4000 messages a day.

His greatest achievement was cracking the Enigma, a mechanical device used by the German army to encode secure messages. It proved nearly impossible to decrypt without the correct cipher, which the German forces changed every day. Turing worked to decipher German naval communications at a point when German U-boats were sinking ships carrying vital supplies across the Atlantic between Allied nations. In 1941, Turing and his team managed to decode the German Enigma messages, helping to steer Allied ships away from the German submarine attacks. In 1942, he traveled to the U.S. to help the Americans with their own codebreaking work.


Early on, Bletchley Park’s operations were hampered by a lack of resources, but pleas for better staffing were ignored by government officials. So, Alan Turing and several other codebreakers at Bletchley Park went over their heads to write directly to Prime Minister Winston Churchill. One of the codebreakers from Bletchley Park delivered the letter by hand in October 1941.

“Our reason for writing to you direct is that for months we have done everything that we possibly can through the normal channels, and that we despair of any early improvement without your intervention,” they wrote to Churchill [PDF]. “No doubt in the long run these particular requirements will be met, but meanwhile still more precious months will have been wasted, and as our needs are continually expanding we see little hope of ever being adequately staffed.”

In response, Churchill immediately fired off a missive to his chief of staff: “Make sure they have all they want on extreme priority and report to me that this had been done.”


Like many geniuses, Turing was not without his eccentricities. He wore a gas mask while riding his bike to combat his allergies. Instead of fixing his bike’s faulty chain, he learned exactly when to dismount to secure it in place before it slipped off. He was known around Bletchley Park for chaining his tea mug to a radiator to prevent it from being taken by other staffers.


Though he was considered an average student, Turing was dedicated enough to his schooling that when a general strike prevented him from taking the train to his first day at his new elite boarding school, the 14-year-old rode his bike the 62 miles instead.


Turing started running as a schoolboy and continued throughout his life, regularly running the 31 miles between Cambridge and Ely while he was a fellow at King’s College. During World War II, he occasionally ran the 40 miles between London and Bletchley Park for meetings.

He almost became an Olympic athlete, too. He came in fifth place at a qualifying marathon for the 1948 Olympics with a 2-hour, 46-minute finish (11 minutes slower than the 1948 Olympic marathon winner). However, a leg injury held back his athletic ambitions that year.

Afterward, he continued running for the Walton Athletic Club, though, and served as its vice president. ”I have such a stressful job that the only way I can get it out of my mind is by running hard,” he once told the club’s secretary. “It's the only way I can get some release."


In 1952, Turing was arrested after reporting a burglary in his home. In the course of the investigation, the police discovered Turing’s relationship with another man, Arnold Murray. Homosexual relationships were illegal in the UK at the time, and he was charged with “gross indecency.” He pled guilty on the advice of his lawyer, and opted to undergo chemical castration instead of serving time in jail.


In 2009, UK Prime Minister Gordon Brown issued a public apology to Turing on behalf of the British government. “Alan and the many thousands of other gay men who were convicted as he was convicted under homophobic laws were treated terribly,” Brown said. "This recognition of Alan's status as one of Britain's most famous victims of homophobia is another step towards equality and long overdue." Acknowledging Britain’s debt to Turing for his vital contributions to the war effort, he announced, “on behalf of the British government, and all those who live freely thanks to Alan's work I am very proud to say: we're sorry, you deserved so much better."

His conviction was not actually pardoned, though, until 2013, when he received a rare royal pardon from the Queen of England.


Turing was only one of the many men who suffered after being prosecuted for their homosexuality under 19th-century British indecency laws. Homosexuality was decriminalized in the UK in 1967, but the previous convictions were never overturned. Turing’s Law, which went into effect in 2017, posthumously pardoned men who had been convicted for having consensual gay sex before the repeal. According to one of the activists who campaigned for the mass pardons, around 15,000 of the 65,000 gay men convicted under the outdated law are still alive.


There is still a bit of mystery surrounding Turing’s death at the age of 41. Turing died of cyanide poisoning, in what is widely believed to have been a suicide. Turing’s life had been turned upside down by his arrest. He lost his job and his security clearance. By order of the court, he had to take hormones intended to “cure” his homosexuality, which caused him to grow breasts and made him impotent. But not everyone is convinced that he died by suicide.

In 2012, Jack Copeland, a Turing scholar, argued that the evidence used to declare Turing’s death a suicide in 1954 would not be sufficient to close the case today. The half-eaten apple by his bedside, thought to be the source of his poisoning, was never tested for cyanide. There was still a to-do list on his desk, and his friends told the coroner at the time that he had seemed in good spirits. Turing’s mother, in fact, maintained that he probably accidentally poisoned himself while experimenting with the chemical in his home laboratory. (He was known to taste chemicals while identifying them, and could be careless with safety precautions.)

That line of inquiry is far more tame than some others, including one author’s theory that he was murdered by the FBI to cover up information that would have been damaging to the U.S.


Alan Turing was a well-respected mathematician in his time, but his contemporaries didn’t know the full extent of his contributions to the world. Turing’s work breaking the Enigma machine remained classified long after his death, meaning that his contributions to the war effort and to mathematics were only partially known to the public during his lifetime. It wasn’t until the 1970s that his instrumental role in the Allies' World War II victory became public with the declassification of the Enigma story. The actual techniques Turing used to decrypt the messages weren’t declassified until 2013, when two of his papers from Bletchley Park were released to the British National Archives.


Can a machine fool a human into thinking they are chatting with another person? That’s the crux of the Turing test, an idea developed by Turing in 1950 regarding how to measure artificial intelligence. Turing argued in his paper “Computing Machinery and Intelligence” [PDF] that the idea of machines “thinking” is not a useful way to evaluate artificial intelligence. Instead, Turing suggests “the imitation game,” a way to assess how successfully a machine can imitate human behavior. The best measure of artificial intelligence, then, is whether or not a computer can convince a person that it is human.


As technology has progressed, some feel the Turing test is no longer a useful way to measure artificial intelligence. It’s cool to think about computers being able to talk just like a person, but new technology is opening up avenues for computers to express intelligence in other, more useful ways. A robot’s intelligence isn’t necessarily defined by whether it can fake being human—self-driving cars or programs that can mimic sounds based on images might not pass the Turing test, but they certainly have intelligence.


Inspired by the chess champions he worked with at Bletchley Park, Alan Turing created an algorithm for an early version of computer chess—although at that time, there was no computer to try it out on. Created with paper and pencil, the Turochamp program was designed to think two moves ahead, picking out the best moves possible. In 2012, Russian chess grandmaster Garry Kasparov played against Turing’s algorithm, beating it in 16 moves. “I would compare it to an early caryou might laugh at them but it is still an incredible achievement," Kasparov said in a statement after the match-up.


In 2012, Monopoly came out with an Alan Turing edition to celebrate the centennial of his birth. Turing had enjoyed playing Monopoly during his life, and the Turing-themed Monopoly edition was designed based on a hand-drawn board created in 1950 by his friend William Newman. Instead of hotels and houses, it featured huts and blocks inspired by Bletchley Park, and included never-before-published photos of Turing. (It’s hard to find, but there are still a few copies of the game on Amazon.)


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