Carl Sagan:

The Life of Doctor Carl E. Sagan, the People’s Astronomer

By Ted N.
Copyright 2000, Astronomical Society of Harrisburg. May not be reused or posted elsewhere without permission.

Carl Edward Sagan was born on November 9, 1934, in Brooklyn, New York. He was the son of Samuel Sagan, a Russian emigrant, and Rachel Gruber Sagan. In his childhood he became fascinated with the stars and was an avid reader of science fiction. He was particularly interested in books by Edgar Rice Burroughs about the exploration of Mars. By the age of five, he was sure he wanted to be an astronomer, but he assumed it was not a paying job. However, he eventually found out that astronomers actually get paid; he was ecstatic, and the rest is history.

agan went through all of his schooling at the University of Chicago. He earned an A.B. in 1954, a B.S. in 1955, an M.S. in physics in 1956, and his Ph.D. in astronomy and astrophysics in 1960. He was extremely interested in the possibility of life on other planets, which is also known as exobiology. He believed this to be beyond the realm of present day scientific exploration but received early support for Nobel laureates Hermann Joseph Muller and Joshua Lederberg. Sagan’s doctoral dissertation was titled "Physical Studies of the Planets."

Carl Sagan, ca 1985

Sagan met his first wife Lynn Alexander and married her on June 16, 1957. They divorced in 1963, having had two sons together before their divorce. Following graduate school Sagan moved to the University of California at Berkeley where he was the Miller Residential Fellow in astronomy from 1960 to 1962. He then accepted a position as assistant professor at Harvard from 1962 to 1968. He married his second wife, the painter Linda Salzman, on April 6, 1968. They had one son together before divorcing.

Sagan’s contributions to science began while he was a graduate student. It was long theorized that the color variations on Mars indicated seasonal change and the possibility of some form of Martian plant life. Working with James Pollack, they postulated that the changing colors were instead caused by Martian dust, shifting via violent wind storms. This interpretation was confirmed in the early 1970’s by Mariner 9.

Sagan also suggested that the surface of Venus was incredibly hot, since the atmosphere was made of carbon dioxide and water vapor, which held in the sun’s heat. He postulated this created a "run-away greenhouse effect." This theory was also confirmed by a spacecraft; this time the Soviet probe Venera IV, in 1967. Sagan then toiled with the idea that the production of organic molecules in an artificial atmosphere simulated that of a primitive Earth or contemporary Jupiter. This work later earned him a patent for a technique that used gaseous mixtures to produce amino acids.

Sagan’s involvement in spaceflight began in 1959, when Lederberg proposed he join a committee on the Space Science Board of the National Academy of Sciences. His involvement increased in the 1960’s when he became involved with many of the key robotic missions sponsored by NASA. He then developed experiments for the Mariner Venus mission. Contributing as a designer, he worked on the Viking Missions to Mars, Pioneer 10, Pioneer 11, and the Voyager spacecrafts.

Pioneer and the Voyager spacecrafts, since they would go out of our solar system, were equipped with a plaque that contained a picture of two humans, a man and a woman. It also contained other assorted astronomical data. The pictures were drawn by Sagan’s second wife, the artist, Linda Salzman. Many denounced Sagan for sending "smut" into space.

http://www-pw.ph ysics.uiowa.edu/pioneer/other/plaque.gif

Sagan accepted a position at Cornell University where he remained until his death in 1996. At Cornell, he was associate professor of astronomy at the Center for Radiophysics and Space Research and professor and associate director of the Center up until 1977, when he accepted promotion to the position of David Duncan Professor of Astronomy and Space Science.

Sagan met his third wife, Ann Druyan, during this time, for she was the creative director of the project. She was also a writer and secretary for the Federation of American Scientists. They had two children together, bringing Sagan’s total number of children up to five. Sagan’s involvement with NASA and spaceflight continued through the 1990’s.

Sagan and Ann Druyan

Sagan worked on the possibility of life on one of Saturn’s moons, Titan. Since the moon contained an atmosphere, he gained the help of Muller, Lederberg, and Urey. He was a key person involved with NASA’s establishment of a radio astronomy program that Sagan called CETI, meaning Communication with Extra-Terrestrial Intelligence. During the early 1970’s, Sagan began to make a number of brief appearances on talk shows and news programs. Johnny Carson invited him on the Tonight Show for the first time in 1972. Sagan became somewhat of a regular there, returning to discuss science a few times each year.

This involvement led to the creation of the TV series Cosmos, which aired on the then newly established Public Broadcasting System. This caused a media sensation for Sagan, for his goal was to educate the general public on the wonders of astronomy. Sagan served as narrator and writer; other writers included his third wife, Ann Druyan, and Steven Soter. Many scientists criticized the series for they believed Sagan brought across speculations which he had the tendency to claim as fact when they were only hypotheses. In his later life Sagan did extensive research and warned of the possibility of a Nuclear Winter. These predictions have turned out to be very accurate.

In 1978 Sagan won the Pulitzer Prize for his book on evolution titled The Dragons of Eden. He won several other awards, including the A. Calvert Smith Prize, NASA’s Apollo Achievement Award, NASA’s Exceptional Scientific Achievement Medal, NASA’s Medal for Distinguished Public Service (twice), the International Astronaut Prize, the John W. Campbell Memorial Award, the Joseph Priestly Award, the Newcomb Cleveland Prize, the Rittenhouse Medal, the Ralph Coats Roe Medal from the American Society of Mechanical Engineers, the Tsiolkovosky Medal of the Soviet Cosmonautics Federation, the Kennan Peace Award, the Oersted Medal of the American Association of Physics, the UCLA Medal, and the Mazursky Award from the American Astronomical Association.

Sagan served as a founder and president of the Planetary Society and served as editor-in-chief for twelve years for the Icarus, a professional journal of planetary studies. Sagan is also widely known for writing the book Contact, now turned into a movie.

To understand Sagan, however, one must first understand what was going on throughout his life. At the time of his birth, President von Hindenburg of Germany died and the Nazi Party purged 77 party members in Germany. During the Presidency of Franklin Delano Roosevelt, Sagan lived through World War II, the Vietnam War, the American Invasion of Grenada, and the Persian Gulf War. Some of his contemporaries included Valentina Tershkova, a Russian cosmonaut, Margaret Joan Geller, an American Astronomer, and Mae C. Jemison, an American astronaut.

Sagan was diagnosed with myelodysplasia, a rare bone marrow disease in the 1990’s. A bone marrow transplant was completed in the mid 1990’s, but in 1996 Sagan contracted pneumonia and died on December 20, 1996. The Mars Pathfinder station was renamed the Dr. Carl Sagan Memorial Station in his memory.

Sagan was long criticized by scientists for doing hardly any research to support his claims, and being more of a "pop" scientist. If one asks many scientists, they will describe him as very arrogant and sometimes rude; however, in the scientific community, when many question a scientist’s theories which keep being verified, it is hard to believe Sagan would not have had reason to be arrogant and dismiss those who had questioned him.

I, however, will remember Sagan as one of the greatest and most admirable people that have walked this Earth, having theorized some of the greatest ideas ever thinkable. I never met the man, but have studied his theories and admire him deeply. In fact, I do not go through a day without thinking about his significance in the field of astronomy.

Carl Sagan truly deserves to be remembered as one of the most important people of the millennium in the scientific realm. Sagan’s contribution to the scientific community will continue to be seen as his theories continue to be verified, and as his writings aid our understanding of outer space, the final frontier.

Bibliography

"Carl Sagan. Online." Gale Research. Discovering BIOGRAPHY. 12/17/99.
"The Life and Times of Carl Sagan." Gale Research. Discovering BIOGRAPHY. 12/17/99.

Internet Resoruces

http://www-pw.physics.uiowa.edu/pioneer/other/plaque.html

http://home.pacific.net.hk/~paulchui/sagan.html

http://www.io.com/~mrapp/sagan/www.html

Copyright, Astronomical Society of Harrisburg, 2003.