Lightning in other planets

Abstract

More than 4000 planet are known that orbit stars other than our Sun. Many harbor a dynamic atmosphere that is cold enough that cloud particles can form in abundance. The diversity of exoplanets leads to differences in cloud coverage depending on global system parameters. Some planets will be fully covered in clouds, some have clouds on the nightside but are largely cloud-free on the dayside. These cloud particles can easily be charged and lightning discharges will occur in cloudy, dynamic exoplanet atmosphere. Lightning supports a Global Electric Circuit (GCE) on Earth and we argue that exoplanet may develop a GCE in particular if parts of the exoplanet atmospheres can remain cloud free.