Viking 1 landed on Mars 50 years ago - The Register

What the report says

The Register reported that NASA’s Viking 1 Mars lander reached the 50-year mark of its touchdown, recalling a mission that became one of the defining early achievements in robotic planetary exploration. Viking 1 launched on August 20, 1975, entered Mars orbit on June 19, 1976, and landed at Chryse Planitia on July 20, 1976, after mission managers moved the planned July 4 landing to allow selection of a safer site.

The spacecraft was part of a two-vehicle Viking program, with each mission including an orbiter and a lander. Viking 1 used a heat shield, parachutes and retro-rockets to descend safely. On the surface, it collected Martian soil with a robotic arm, ran biology experiments and sent back images from the planet. NASA’s position, as cited by The Register, was that the experiments showed unusual chemical behavior in the soil but did not provide clear evidence of microorganisms.

The lander far outlasted its 90-day primary mission, helped by a radioisotope thermoelectric generator that produced power from plutonium-238 decay heat. Its last transmission came on November 11, 1982. The Register highlighted that the end may have been avoidable: while engineers were trying to extend battery life, a revised charging sequence uploaded later that month overwrote memory used for high-gain antenna pointing, leaving the antenna no longer aimed at Earth.

Attempts to re-establish contact continued for months, but the Viking Lander Monitor Mission ended in March 1983. Although the Soviet Mars 3 had achieved an earlier soft landing in 1971, Viking 1 operated for years and returned a major scientific and visual record from the Martian surface.