Atmospheric Electricity on Mars: Tantalizing and Enigmatic

The atmosphere of Mars is one compelling example in our solar system that should possess active electrical processes, where dust storms are known to occur on local, regional, and global scales. Laboratory experiments and simulations all indicate that dust activity on Mars is expected to generate substantial quasi-static electric fields via triboelectric (i.e., frictional) charging. If present, significant atmospheric electricity could be an important source of atmospheric chemistry on Mars, and thus impact our understanding of the evolution of the atmosphere and its past or present astrobiological potential. However current observations of potential electrical activity on Mars from both ground-based and orbital platforms have yielded conflicting results. Thus whether or not triboelectric charging processes generate large scale electrical discharges analogous to terrestrial lightning remains an open question. Here we review the current state of understanding regarding atmospheric electricity on Mars, and discuss its implications pending the results of future measurements.