~carl-sagan
What is Carl Sagan known for in relation to extraterrestrial life?
What were Carl Sagan's contributions to the search for extraterrestrial intelligence?
Who did Carl Sagan collaborate with to advocate for the search for extraterrestrial life?
Who is Carl Sagan?
What was Carl Sagan's stance on the search for extraterrestrial life?
What was Carl Sagan's association with the U.S. space program?
What organization was Carl Sagan the faculty adviser for?
What were Carl Sagan's contributions to NASA?
What is Carl Sagan known for?
What organizations did Carl Sagan co-found?
What organizations was Carl Sagan associated with?
What sparked Carl Sagan's interest in space?
Who was Carl Sagan?
Who did Carl Sagan work with during his graduate studies?
What were Carl Sagan's main areas of research?