Mars before Viking - Lecture 4

Explore the groundbreaking discoveries made by Mariner 9, the first unmanned space probe to orbit another planet, in this fourth lecture from Carl Sagan's 1977 Christmas Lectures series. Delve into the surprising features of Mars uncovered by the mission, including crater formations, volcanoes, polar regions, and intriguing winding valleys and tributaries. Learn how these findings challenged scientists' expectations and provided evidence of significant climate change on the Red Planet, hinting at the possibility of past conditions suitable for terrestrial life. Gain insights into the evolution of planetary exploration and its impact on our understanding of the solar system in this hour-long presentation from The Royal Institution.