Dust cloud lightning in extraterrestrial atmospheres
arXiv:1207.1907 · doi:10.1016/j.pss.2012.07.003
Abstract
Lightning is present in all solar system planets which form clouds in their atmospheres. Cloud formation outside our solar system is possible in objects with much higher temperatures than on Earth or on Jupiter: Brown dwarfs and giant extrasolar gas planets form clouds made of mixed materials and a large spectrum of grain sizes. These clouds are globally neutral obeying dust-gas charge equilibrium which is, on short timescales, inconsistent with the observation of stochastic ionization events of the solar system planets. We argue that a significant volume of the clouds in brown dwarfs and extrasolar planets is susceptible to local discharge events and that the upper cloud layers are most suitable for powerful lightning-like discharge events. We discuss various sources of atmospheric ionisation, including thermal ionisation and a first estimate of ionisation by cosmic rays, and argue that we should expect thunderstorms also in the atmospheres of brown dwarfs and giant gas planets which contain mineral clouds.
refereed conference paper accepted for publication in PSS Special Issue: Outer Planets VIII, 16 pages
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Cited by in corpus (6)
- M-dwarf stellar winds: the effects of realistic magnetic geometry on rotational evolution and planets
- A Chemical Kinetics Network for Lightning and Life in Planetary Atmospheres
- Atmospheric Regimes and Trends on Exoplanets and Brown Dwarfs
- Ionization in atmospheres of Brown Dwarfs and extrasolar planets IV. The Effect of Cosmic Rays
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- Lightning-induced chemistry on tidally-locked Earth-like exoplanets