On this day in 1976, the Viking 2 Mars lander touched down on the red planet, becoming only the second spacecraft to successfully soft-land on Mars. Viking 2 remained active for over three years, returning extremely valuable data on the planet’s surface composition and amazing photos that are still in use today.
Viking 2 carried instrumentation to conduct three biology experiments which discovered “unexpected and enigmatic chemical activity in the Martian soil,” and prompted the development of new biological research instruments for future landers.