Viking 1 entered into a Mars orbit on June 19, 1976. In order to find a good landing location it began taking pictures of the surface and then made that landing the next day in location Chryse Planitia. It was the second ever landing of a manmade craft on the surface of Mars and the first lander to function over a long period of time.
The lander took weather readings and soil samples using a scoop.
Launched on May 28, 1971 the two spacecraft arrived at Mars on December 2, 1971. Both craft had Mars landers but only Mars 3 survived the, at the time, ongoing dust storms – making it the first successful landing on Mars. After touching down the lander survived for 20 seconds before failing. The lander also possibly deployed the first ever rover onto the Mars surface.
After several orbits around Mars, Mars 2 & 3 returned 60 images, recorded temperature ranges from -110 to 13 degrees celsius. They also produced surface relief maps and studied the planets gravity and magnetic field.