- 1Department of Industrial Engineering, University of Bologna, Forlì, Italy
- 2Centro Interdipartimentale di Ricerca Industriale Aerospaziale, University of Bologna, Forlì, Italy
- 3Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot, Israel
- 4Boston University, Boston, MA, USA
- 5Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
- 6Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ, USA
- 7School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, USA
- 8Southwest Research Institute, San Antonio, TX, USA
The Juno extended mission (2023–2025) offers a unique opportunity to study Jupiter’s atmosphere by radio occultations. In these experiments, the atmospheric refractivity and the bending angle affecting a radio signal crossing a planetary atmosphere can be inferred by analyzing the Doppler shift induced on the downlink frequencies, at X and Ka bands, recorded at NASA Deep Space Network stations. The analysis is conducted using a ray-tracing-based inversion algorithm that accounts for Jupiter’s oblateness and the effects of zonal winds.
The objectives of these experiments are to measure pressure-temperature profiles across different depths and latitudes of the Jovian atmosphere, with the goal of understanding its complex dynamics. Also, radio occultations’ results may help us understand the structure of the ionosphere, particularly in polar regions, by exploiting the availability of sky frequencies recorded at two different bands, X and Ka, to isolate the dispersive contribution to the Doppler shift. These ionospheric results aim at investigating the aurora’s influence on the rest of the planet.
Starting with perijove 63 in July 2024, Juno’s radio occultations have started probing the polar regions above 60°N, including areas near the auroral zones. The aim of this work is to present the results of the analysis of recent polar occultations, providing pressure-temperature profiles of the neutral atmosphere and electron density profiles of the ionosphere. Additionally, we present the results of an error quantification analysis, which accounts for various factors such as noise in the Doppler observables, uncertainties in wind measurements, unknown boundary value of temperature at a specific pressure level, and uncertainties in Juno's trajectory. This comprehensive analysis allows us to evaluate the uncertainties associated with the computed atmospheric profiles. As Juno continues its extended mission, ongoing radio occultation experiments will further refine these results, shedding new light on the intricate dynamics and structure of Jupiter’s atmosphere.
How to cite: Caruso, A., Gomez Casajus, L., Smirnova, M., Coffin, D., Buccino, D., Galanti, E., Gramigna, E., Parisi, M., Togni, A., Zannoni, M., Tortora, P., Park, R. S., Kaspi, Y., Withers, P., Hubbard, W., Steffes, P., and Bolton, S.: Radio Occultations with Juno: Unveiling the Structure of Jupiter’s Polar Atmosphere and Ionosphere, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-16362, https://doi.org/10.5194/egusphere-egu25-16362, 2025.
