Technicians working on the aeroshell of a Mars Viking Lander, 1974.
© National Aeronautics & Space Administration / Science & Society
The aeroshell protected the Lander as it entered the atmosphere of Mars prior to landing on the surface. Two Viking spacecraft were launched towards Mars in 1975, each carrying a lander spacecraft and an orbiter. Both succesfully landed their probes on Mars to study the Martian environment, soil constituents and to search for simple life forms - none were found.