Mariner 4 changed Mars forever

Transcript

Before 1965, many Mars planners still pictured a world with canals, maybe even life, and spacecraft designs aimed at warm equatorial landing sites. Then Mariner 4 flew past Mars on July 15, 1965 and sent back the first close pictures of another planet. The images showed a cratered, Moon-like surface, and its radio data revealed an atmosphere less than one percent as dense as Earth’s. That one flight shattered the old canal idea, weakened the case for caretaker flybys, and pushed designers toward heavier rocket landings, stronger shielding, and much harder risk tradeoffs for future Mars missions.