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Carl Sagan

Astronomer Carl Sagan died Friday, 20 December 1996, of pneumonia at age 62. He died at the Fred Hutchinson Cancer Research Center in Seattle after a two-year battle with bone marrow disease.

Sagan was well known as a popularizer of science, and was one of the co-authors of the famous TTAPS study (Turco, Toon, Ackerman, Pollack, and Sagan) that suggested the possibility of drastic smoke-induced climatic cooling ("Nuclear Winter") as a consequence of large scale nuclear war. The study was published in Science Vol. 222, 1983, Global Atmospheric Consequences of Nuclear War, pg. 1283.

This discovery was greeted by considerable controversy, especially from the political right who curiously found the possibility that large-scale nuclear war might have disastrous consequences to be unacceptable. More than a decade of subsequent study by hundreds of researchers, using progressively more sophistcated computer models, has essentially confirmed the original estimates with only minor revisions.

In addition to this article, Sagan also wrote or contributed to two books on the subject:

A follow-up to the original TTAPS article (often referred to as TTAPS II) was publsihed in 1990:
R.P. Turco, O.B. Toon, T.P. Ackerman, J.B. Pollack, C. Sagan. 1990. Climate and Smoke: An Appraisal of Nuclear Winter, Science Vol. 247, pg. 166-176.