One Mars year - Viking lander imaging observations
The imaging systems on board the two Viking landers have documented eolian processes and condensate formation on the Martian surface during the first Mars year of operation. During the winter, the formation of what appeared to be solid H2O and CO2 at the Viking 2 lander site was noted. The condensate formation suggested that solar radiative heating dominates atmospheric conductive heating on Mars. In addition, the Viking observations indicated that Martian surface erosion due to dust distribution may be lower than previously thought.
Jones, K. L.↗