Exoplanets & Exomoons

Cloud Formation In Exoplanetary Atmospheres

By Keith Cowing

astro-ph.EP

May 2, 2022

Filed under exoplanet

Cloud Formation In Exoplanetary Atmospheres — Cloud formation processes: First, condensation seeds form through gas-gas collisions either directly in the gas phase or triggered by photo-chemistry. Secondly, these condensation seeds grow through gas-surface reaction which grow the bulk of the cloud particle mass. These cloud particles gravitatiallly settle into the deeper, denser and also warmer atmospheric layers. They may coagulate and form larger particles or they may shatter through particle-particle collisions. At higher temperature, the cloud particles evaporate. Convective or diffusive mixing may cause element replenishment.

This invited review for young researchers presents key ideas on cloud formation as key part for virtual laboratories for exoplanet atmospheres.

The basic concepts are presented, followed by utilising a time-scale analysis to disentangle process hierarchies. The kinetic approach to cloud formation modelling is described in some detail to allow the discussion of cloud structures as prerequisite for future extrasolar weather forecasts.

Christiane Helling

Comments: 21 pages, 6 figures; accepted as a chapter in the book “Planetary systems now”, eds. Luisa M. Lara and David Jewitt, World Scientific Publishing Co Pte Ltd
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR); Computational Physics (physics.comp-ph); Space Physics (physics.space-ph)
Cite as: arXiv:2205.00454 [astro-ph.EP] (or arXiv:2205.00454v1 [astro-ph.EP] for this version)
Submission history
From: Christiane Helling
[v1] Sun, 1 May 2022 12:00:53 UTC (2,699 KB)
https://arxiv.org/abs/2205.00454
Astrobiology

Keith Cowing

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻

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