Open/Close All Full Name: Carl Edward Sagan Born: Nov. 9, 1934 in Brooklyn, New York Died: Dec. 20, 1996 in Seattle, WashingtonCarl Sagan was a renowned astrophysicist, cosmologist and author whose inquiring mind and unique view of his native planet transformed him into a political activist. His views on extraterrestrial intelligence, religion and nuclear weapons made him controversial far beyond the scientific arena. Sagan even advocated the use of marijuana — not just in medicine but in enhancing intellectual pursuits.Sagan is remembered primarily as a spokesman for science and a popularizer of astronomy; he was probably the best-known scientist in the United States in the 1970s and 80s. In 1980, he co founded the Planetary Society and reached the height of his public fame with the television series Cosmos, which he co-wrote (with his wife) and narrated.Sagan’s research led him to believe that extraterrestrial civilizations form in large numbers but tend to self-destruct. This fueled his fear that humans might destroy themselves, particularly through nuclear warfare, an idea he publicized in the final episode of Cosmos, called “Who Speaks for Earth?” Sagan had already resigned from the Air Force Scientific Advisory Board and voluntarily surrendered his top secret clearance in protest over the Vietnam War. In 1981, Sagan became more politically active, particularly in opposing escalation of the nuclear arms race under President Ronald Reagan.In 1983 Sagan co-wrote the paper that introduced the concept of “nuclear winter,” a catastrophic global cooling that would result from a nuclear war. He was also co-author of The Cold and the Dark: The World After Nuclear War (1984).Sagan spoke out against Reagan’s “Star Wars” program, arguing that the multi-billion dollar project was doomed to failure and would seriously destabilize the nuclear balance between the U.S. and the Soviet Union, making further progress toward nuclear disarmament impossible. When Soviet leader Mikhail Gorbachev declared a unilateral moratorium on nuclear weapons testing to begin on August 6, 1985 — the 40th anniversary of the atomic bombing of Hiroshima — the Reagan administration dismissed the dramatic gesture as propaganda. Sagan was one of hundreds of people arrested (twice) in ensuing protests staged at the Nevada Test Site (1986-87).Anything else you’re interested in is not going to happen if you can’t breathe the air and drink the water. Don’t sit this one out. You are by accident of fate alive at an absolutely critical moment in the history of our planet.Activists | Intellectuals | Writers Related Resources, Notes, Links, etc. See the Geopeda version of this article.