Temperature, Clouds, and Aerosols in Giant and Icy Planets

  • Robert A. WestEmail author
Reference work entry


As observations (transit spectra and secondary eclipse spectra) of extrasolar planets accumulate, it has become clear that clouds and haze are prevalent in the Neptune–Jupiter-sized planets. Clouds and haze have a profound influence on the spectra and must be understood to make sensible interpretation of the data. High-temperature atmospheres are likely to contain condensates of dense materials (minerals and metals), and this presents a challenge to understand how such particles can be maintained high in the atmosphere. Perhaps photochemical haze is the more important aerosol at high altitude, but more work needs to be done to understand its formation and stability. This chapter summarizes the salient observations and ideas about temperature, clouds, and haze in gas and ice giant planets with emphasis on lessons learned from studies in our own solar system.


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© This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply 2018

Authors and Affiliations

  1. 1.Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaUSA

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