Carl Edward Sagan was an American astronomer, planetary scientist, cosmologist, astrophysicist, astrobiologist, author, and science communicator.

When and how did Carl Sagan die?

Carl E. Sagan, the David Duncan Professor of Astronomy and Space Sciences and director of the Laboratory for Planetary Studies at Cornell University, died today, Dec. 20, 1996, in Seattle, Wash., after a two-year battle with a bone marrow disease. The cause of death was pneumonia.

How did Carl Sagan pass away?

Sagan died of pneumonia at the Fred Hutchinson Cancer Research Center in Seattle, where he had a bone-marrow transplant in April 1995, said center spokeswoman Susan Edmonds.