Scientists who died on December 20

Take a focused look at the scientists who passed away on December 20. Dive into curated bios, achievements, and cultural milestones verified by our editors.

• 1996 Carl Sagan

  Carl Sagan was an American astronomer, astrophysicist, planetary scientist, cosmologist, author, and science communicator best known for popularizing science and his research on extraterrestrial life. [bio]