structural:scholar_edition, structural:expansion
Education

Sagan attended David A. Boody Junior High School in his native Bensonhurst and had his bar mitzvah when he turned 13. In 1948, when he was 14, his father's work took the family to the older semi-industrial town of Rahway, New Jersey, where he attended Rahway High School. He was a straight-A student but was bored because his classes did not challenge him and his teachers did not inspire him. His teachers realized this and tried to convince his parents to send him to a private school, with an administrator telling them, "This kid ought to go to a school for gifted children, he has something really remarkable." However, his parents could not afford to do so. Sagan became president of the school's chemistry club, and set up his own laboratory at home. He taught himself about molecules by making cardboard cutouts to help him visualize how they were formed: "I found that about as interesting as doing experiments." He was mostly interested in astronomy, learning about it in his spare time. In his junior year of high school, he discovered that professional astronomers were paid for doing something he always enjoyed, and decided on astronomy as a career goal: "That was a splendid day—when I began to suspect that if I tried hard I could do astronomy full-time, not just part-time." Sagan graduated from Rahway High School in 1951.

Before the end of high school, Sagan entered an essay writing contest in which he explored the idea that human contact with advanced life forms from another planet might be as disastrous for people on Earth as Native Americans' first contact with Europeans had been for Native Americans. The subject was considered controversial, but his rhetorical skill won over the judges and they awarded him first prize. When he was about to graduate from high school, his classmates voted him "most likely to succeed" and put him in line to be valedictorian. He attended the University of Chicago because, despite his excellent high school grades, it was one of the very few colleges he had applied to that would consider accepting a 16-year-old. Its chancellor, Robert Maynard Hutchins, had recently retooled the undergraduate College of the University of Chicago into an "ideal meritocracy" built on Great Books, Socratic dialogue, comprehensive examinations, and early entrance to college with no age requirement.

As an honors-program undergraduate, Sagan worked in the laboratory of geneticist H. J. Muller and wrote a thesis on the origins of life with physical chemist Harold Urey. He also joined the Ryerson Astronomical Society. In 1954, he was awarded a Bachelor of Arts with general and special honors in what he quipped was "nothing." In 1955, he earned a Bachelor of Science in physics. He went on to do graduate work at the University of Chicago, earning a Master of Science in physics in 1956 and a Doctor of Philosophy in astronomy and astrophysics in 1960. His doctoral thesis, submitted to the Department of Astronomy and Astrophysics, was entitled Physical Studies of the Planets. During his graduate studies, he used the summer months to work with planetary scientist Gerard Kuiper, who was his dissertation director, as well as physicist George Gamow and chemist Melvin Calvin. The title of Sagan's dissertation reflected interests he had in common with Kuiper, who had been president of the International Astronomical Union 's commission on "Physical Studies of Planets and Satellites" throughout the 1950s.

In 1958, Sagan and Kuiper worked on the classified military Project A119, a secret U.S. Air Force plan to detonate a nuclear warhead on the Moon and document its effects. Sagan had a Top Secret clearance at the Air Force and a Secret clearance with NASA. In 1999, an article published in the journal Nature revealed that Sagan had included the classified titles of two Project A119 papers in his 1959 application for a scholarship to University of California, Berkeley. A follow-up letter to the journal by project leader Leonard Reiffel confirmed Sagan's security leak.