James Webb Space Telescope Feed Post

Date: 6/13/2024

Arxiv: Temperature and composition disturbances in the southern auroral region of Jupiter revealed by JWST/MIRI Published: 6/12/2024 3:23:28 PM Updated: 6/12/2024 3:23:28 PM

Paper abstract: Jupiters south polar region was observed by JWST Mid Infrared Instrument inDecember 2022. We used the Medium Resolution Spectrometer mode to provide newinformation about Jupiters South Polar stratosphere. The southern auroralregion was visible and influenced the atmosphere in several ways. 1: In theinterior of the southern auroral oval, we retrieved peak temperatures at twodistinct pressure levels near 0.01 and 1 mbar, with warmer temperatures withrespect to non auroral regions of 12 pm 2 K and 37 pm 4 K respectively. A coldpolar vortex is centered at 65S at 10 mbar. 2: We found that the homopause iselevated to 590+25-118 km above the 1-bar pressure level inside the auroraloval compared to 460+60-50 km at neighboring latitudes and with an upperaltitude of 350 km in regions not affected by auroral precipitation. 3: Theretrieved abundance of C2H2 shows an increase within the auroral oval, and itexhibits high abundances throughout the polar region. The retrieved abundanceof C2H6 increases towards the pole, without being localized in the auroraloval, in contrast with previous analysis. We determined that the warming at0.01 mbar and the elevated homopause might be caused by the flux of chargedparticles depositing their energy in the South Polar Region. The 1 mbar hotspotmay arise from adiabatic heating resulting from auroral driven downwelling. Thecold region at 10 mbar may be caused by radiative cooling by stratosphericaerosols. The differences in spatial distribution seem to indicate that thehydrocarbons analyzed are affected differently by auroral precipitation.