For over 50 years, NASA and other space agencies have been sending spacecraft to Mars. Today, a human mission to the Red Planet grows near. The foundational mission for expeditions to the Martian surface took place 40 years ago this week.
The Viking program sent the Viking 1 and 2 landers to Mars in August, 1975. Viking 1 landed on July 20, 1976, with Viking 2 following a few weeks later.
This ground-breaking program generated impressive new technologies, but, the heart of the mission was about science. It's goal was to learn and discover.
And discover it did. The Viking program missions returned to Earth 55,000 images of the Martian surface from orbit, another 55,000 images from the surface of the Red Planet, details about the planet's atmosphere and composition.