The Viking results - The case for man on Mars

The Viking landers have provided a number of insights into the composition of the Martian atmosphere and soils (e.g. the high Ar-40/Ar-36 ratio in the atmosphere, and the very low level of organic molecules in the Martian soil). However, a manned mission to Mars could yield much needed additional information on the planet. Seismic and electromagnetic sounding surveys, cloud tracking, drilling for permafrost, and the deduction of geologic field relationships are among the tasks for which a manned research endeavor is particularly suited. Rocket propellant synthesis and the production of food on Mars may be necessary to support such a manned mission.