Jupiter polar Atmosphere & Fate of AeRosols – JAFAR

The "Jupiter Polar Atmosphere & Fate of AeRosols" (JAFAR) project aims to address key questions about the chemistry and aerosol formation in Jupiter's polar atmosphere, a region dominated by strong electron auroral precipitation. This study will investigate how ion-neutral reactions, currently largely unexplored in models, affect the observed spatial distribution of hydrocarbons, hydrogen cyanide (HCN), carbon monosulfide (CS), and aerosols. Ground-based observations and data from science missions such as Cassini and Juno have revealed discrepancies that existing neutral chemical models cannot explain, pointing to ion-neutral chemistry as a likely cause.

JAFAR will develop comprehensive photochemical models and experimental frameworks to simulate the interactions between ions and neutral species in Jupiter’s auroral regions. The project is structured into three work packages (WP): (1) photochemical modeling of Jupiter's polar regions, (2) analysis of observational data to constrain auroral-related chemical species, and (3) experimental investigations into the reactivity of HCN on aerosol analogs. WP1 will adapt a Titan-based chemical network to Jupiter, integrating an electron transport model and expanding to a 2D framework, to simulate the jovian auroral chemistry. WP2 will focus on observations, leveraging data from ALMA, JWST, and other instruments to identify key compounds, providing constraints on the models. Laboratory experiments, as part of WP3, will simulate Jupiter's polar conditions, investigating how aerosols interact with gas-phase species, particularly HCN, to better understand their role in atmospheric chemistry.

The JAFAR project is timely aligned with JUICE's upcoming exploration of the Jupiter system in 2031, helping the scientific community prepare to maximize the mission's science return. The project will enhance our understanding of Jupiter's atmospheric processes, and, in a broader context, of gas giant exoplanets.