Bruce Murray Space Image Library

Carl Sagan discussing Venus in 1963

Carl Sagan discussing Venus in 1963
Carl Sagan discussing Venus in 1963 This image from the 1963 NASA film "The Clouds of Venus" shows Carl Sagan, a Harvard assistant professor still years away from becoming a well-known science communicator, discussing the possibility that high temperatures and pressures measured on Venus might only pertain to the atmosphere, not the surface. Sagan later refined his thinking after additional data showed the opposite to be true. NASA

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