Particle precipitation is an important energy input to the planet’s upper atmosphere, causing heating, ionization, and emission (aurora). It can significantly perturb the planetary ionospheres and thermospheres, altering the compositions and conductivities, and thus influencing the magnetospheric dynamics. Particle precipitation can arise from various physical processes in the magnetosphere system, such as wave-particle interactions, parallel acceleration, field line curvature scattering, or solar energetic particle (SEP) events. With the increased availability of in-situ data from both the Earth and other planets in the Solar System, our knowledge of the complex coupling of processes that lead to the energization of particles and their effects on planets’ upper atmosphere is growing every day. Therefore, studying the impacts of precipitating particles on both the Earth and other planets’ upper atmosphere as well as their origins are crucial for unveiling the underlying physics within the planetary space environment and ultimately for advancing the knowledge of our solar system.This Research Topic seeks contributions in revealing sources, characteristics, and responsible processes of particle precipitation, and consequent impacts on planets’ thermosphere and ionosphere, as well as the feedback effects within the integrated system.This Research Topic will look for original research papers, commentaries, and review papers mainly focusing on:1) Physical processes associated with various types of particle precipitation in both the Earth and other planet systems (e.g., Mars, Mercury, Jupiter, Saturn), including plasma waves, pulsating aurora, different types of auroral forms, SEP events, and other potential mechanisms.2) The wide range of responses in the planets' thermosphere-ionosphere system to particle precipitation, including variations of neutral/electron density and velocity, temperature variability and irregularity, ion upwelling and outflow, composition variation, energy deposition and dissipation, electromagnetic and ground magnetic fluctuations.
Particle precipitation is an important energy input to the planet’s upper atmosphere, causing heating, ionization, and emission (aurora). It can significantly perturb the planetary ionospheres and thermospheres, altering the compositions and conductivities, and thus influencing the magnetospheric dynamics. Particle precipitation can arise from various physical processes in the magnetosphere system, such as wave-particle interactions, parallel acceleration, field line curvature scattering, or solar energetic particle (SEP) events. With the increased availability of in-situ data from both the Earth and other planets in the Solar System, our knowledge of the complex coupling of processes that lead to the energization of particles and their effects on planets’ upper atmosphere is growing every day. Therefore, studying the impacts of precipitating particles on both the Earth and other planets’ upper atmosphere as well as their origins are crucial for unveiling the underlying physics within the planetary space environment and ultimately for advancing the knowledge of our solar system.This Research Topic seeks contributions in revealing sources, characteristics, and responsible processes of particle precipitation, and consequent impacts on planets’ thermosphere and ionosphere, as well as the feedback effects within the integrated system.This Research Topic will look for original research papers, commentaries, and review papers mainly focusing on:1) Physical processes associated with various types of particle precipitation in both the Earth and other planet systems (e.g., Mars, Mercury, Jupiter, Saturn), including plasma waves, pulsating aurora, different types of auroral forms, SEP events, and other potential mechanisms.2) The wide range of responses in the planets' thermosphere-ionosphere system to particle precipitation, including variations of neutral/electron density and velocity, temperature variability and irregularity, ion upwelling and outflow, composition variation, energy deposition and dissipation, electromagnetic and ground magnetic fluctuations.