Topic: Carl Edward Sagan

Carl Edward Sagan , 1934-96, American astronomer and popularizer of science, b. New York City. Early in his career he investigated radio emissions from Venus and concluded that the cause was a surface temperature of c.900°F (500°C) and crushing atmospheric pressure. He also studied color variations on Mars' surface, concluding that they were not seasonal changes as most believed but shifts in surface dust caused by windstorms. Both conclusions were substantially confirmed years later by space probes. Sagan is best known, however, for his research on the possibilities of extraterrestrial... Read more