Mars 1973

Relief shown by shading.; Each major map centered on a different meridian: 120⁰, 0⁰, a; "Supplement to National geographic, February, 1973 ..."; Includes text, diagrams of solar system, the moons of Mars, etc., and maps of the north and south polar areas.; Text, color illustrations, index, and diagrams on verso.; Scale 1:31,770,000. "One degree of longitude on the equator and one degree of latitude equal 36.7 statute miles or 59.1 kilometers."Color;1:31,770,00