Carl Sagan was married later in his life to Ann Druyan, a science communicator, author, and television producer. They married in 1981 and remained together until Sagan died in 1996.
Druyan collaborated closely with Sagan on several major projects. She was a creative director of the Voyager Golden Record, the time capsule carried aboard the Voyager spacecraft, and co-wrote the television series Cosmos: A Personal Voyage with Sagan and Steven Soter. She also co-authored the book Comet with Sagan and later helped develop Cosmos: A Spacetime Odyssey.
The question can cause confusion because Sagan had been married before. His earlier wives included biologist Lynn Margulis and artist Linda Salzman. Druyan was not merely a spouse in his biography: she was a significant intellectual and creative partner whose work shaped how modern astronomy and space exploration were presented to the public.