Mention NASA’s Viking mission to Mars in 1976 and its first-of-its-kind in situ search for life on another planet immediately comes to mind. While astrobiological experiments certainly dominated the science objectives of the Viking landers, other investigations were also performed in NASA’s first Mars landing mission such as meteorology and determining the composition of the soil. Almost completely forgotten today is another first-of-its-kind investigation: seismology on the surface of Mars.
Diagram showing the placement of instruments on NASA’s Viking lander. Click on image to enlarge. (NASA/JPL)
The Viking Seismometers
The Principle Investigator for Viking’s seismology investigation since its inception in 1969 was American geophysicist, Don L. Anderson (1933-2014), of the California Institute of Technology – the parent organization of the Jet Propulsion Laboratory (JPL) which was responsible for Viking mission operations. While a highly sensitive seismometer placed directly on the Martian surface of the sort flown to the Moon during the Apollo program would have been ideal for detecting “Marsquakes” and begin the investigation of Mars’ internal structure, restrictions on instrument mass, power and data downlink bandwidth (not to mention budget!) made this impractical. Instead, Viking’s seismometers were mounted on top of the lander’s equipment bay adjacent to Leg #1 ...