Phase II Final Report - NASA's Institute for Advanced Concepts

Chapter 2.0 Entomopter Configuration and Operation
2.4 Environmental Conditions for Flight on Mars
Figure 2-12: Wind Direction Throughout the Day (Pathfinder Data)
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Dust storms tend to occur when Mars is near perihelion, when the solar intensity is the greatest.
It is believed that the greater intensity of solar radiation, coupled with variations in the topology
of Mars, triggers the dust storms. The storms can last up to several months, and the opacity of
the storms can be quite high. Due to the low atmospheric density, these dust storms result in only
minimal distribution and accumulation of debris. More information on dust storms, gathered for
the Mars micromission aircraft program is given in [47].
Dust devils are short-term variations in measured surface pressure, wind velocity, and air temperature
over periods of tens of seconds to minutes, shown in Figure 2-13. Dust devils, about 2
km wide and a few kilometers high, have been observed in the tropics by the Viking orbiters.
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