Happy birthday to Carl Sagan today! To celebrate Carl Sagan Day, you could watch the introduction to the Cosmos series, which is still the most popular science program ever produced for television*:

Or you could read this from Ann Druyan, which is simultaneously heartbreaking and joyful:

Carl faced his death with unflagging courage and never sought refuge in illusions. The tragedy was that we knew we would never see each other again…But the great thing is that when we were together, for nearly twenty years, we lived with a vivid appreciation of how brief and precious life is…We knew we were beneficiaries of chance. That pure chance could be so generous and so kind; that we could find each other, as Carl wrote so beautifully in Cosmos, you know, “in the vastness of space and the immensity of time”; that we could be together for twenty years; that is something which sustains me…That is so much more important than the idea I will see him someday. I don’t think I’ll ever see Carl again. But I saw him. We saw each other. We found each other in the cosmos, and that was wonderful.

Happy birthday, Carl. I like to picture you somewhere in that “ship of the imagination” from Cosmos.

*You’ve all heard that a sequel to Cosmos is in the works for 2013, right? Ann Druyan is helping to write/produce and Neil DeGrasse Tyson will host. I can’t wait.