Today Carl Sagan would have been 75 years old. You can read about him on Wikipedia (did you know that “a Sagan has been defined as a humorous unit of measurement equal to at least four billion”?), watch all of the Cosmos series on Hulu, or watch the “re-mix” below, which was up on last month. Despite the Auto-Tune, it’s meant in a spirit of love, not mockery, and I bet Sagan would have liked it.