Carl Sagan

Carl Edward Sagan was an American astronomer, planetary scientist, and science communicator who brought the wonder of the cosmos into millions of living rooms. Born in Brooklyn, New York, he earned his doctorate at the University of Chicago and went on to become a professor at Cornell University. As a scientist, Sagan made significant contributions to planetary science: he correctly predicted that Venus's extreme temperatures were caused by a runaway greenhouse effect, identified the reddish haze on Titan as complex organic molecules (tholins), and helped plan and interpret data from Mariner, Viking, Voyager, and Galileo missions. But it was as a communicator that Sagan had his greatest impact. His 1980 television series Cosmos: A Personal Voyage became the most-watched PBS series in history, inspiring an entire generation of scientists and space enthusiasts. His novel Contact (1985) explored the search for extraterrestrial intelligence. Sagan championed the Search for Extraterrestrial Intelligence (SETI) and designed the Pioneer plaque and Voyager Golden Record, messages from Earth sent to the stars.

Correctly explained Venus's extreme surface temperature via the runaway greenhouse effect. Created Cosmos: A Personal Voyage (1980), inspiring millions to look up at the stars. Designed the Pioneer plaque and Voyager Golden Record — humanity's messages to the cosmos. Pioneer of exobiology and the search for extraterrestrial intelligence (SETI). Predicted the existence of organic molecules (tholins) on Titan, confirmed by the Cassini-Huygens mission.