What did Carl Sagan do for me?
He taught me that it was OK to ask "why", forever. He served as a role model in that regard.
He also served as a role model of scientist as communicator.
Because of Carl Sagan, when we got an Encyclopedia Britannica (we may have been poor, back then, in the pre-Internet days, but we with the Britannica were wealthy beyond dreams) I browsed it. And romped through it. And chewed my way across it.
I learned about special relativity long before taking a physics class. What cool stuff! Such knowledge! All in one place! I reveled in it. REVELED IN IT.
Because of Carl Sagan, I knew science was cool, education was cool, learning was cool, long before anyone came along to try and peer-pressure me out of it. (Whether because I was a girl or because of some mistaken belief that ignorance = hip.) The peer pressure didn't take.
I learned about history, geology, DNA, evolution, Galileo, gravity, Voyager, and the birth and death of the universe from Carl Sagan. He opened up all of human knowledge to me, and did it with passion and articulate grace.
As if I were a little duckling, he imprinted me to science. Thank you, Dr. Sagan.