The crossword solution for the term 'STAR IN ASTRONOMY' is Sagan, which is a five letter word. Sagan refers to Carl Sagan, an American astronomer, astrophysicist, cosmologist, author, and science communicator. He is best known for his work as a science popularizer and communicator, and he popularized the term 'COSMOS'. Sagan was also an avid advocate for the Search for Extraterrestrial Intelligence (SETI). He was awarded the Pulitzer Prize for General Non-Fiction in 1978 for his book 'The Dragons of Eden: Speculations on the Evolution of Human Intelligence'.