NASA sends Viking 1 toward Mars

NASA had spent seven years developing Viking 1 to do something no American spacecraft had done: land intact on Mars and search its soil for life. On August 20, 1975, Viking 1 lifted off, carrying an orbiter and a lander built to work as one unit until they reached the planet. The probe would not arrive until the following June. Its twin, Viking 2, was scheduled to follow about three weeks later…