Skip to main content
SearchLoginLogin or Signup

Radio Occultation Studies of Jupiter’s Ionosphere and Atmosphere with the Juno Spacecraft: PJ-53 and PJ-54 – First Opportunities

Presentation #309.01 in the session Giant Planet Magnetospheres, Ionospheres and Aurorae (Oral Presentation)

Published onOct 23, 2023
Radio Occultation Studies of Jupiter’s Ionosphere and Atmosphere with the Juno Spacecraft: PJ-53 and PJ-54 – First Opportunities

The Juno Spacecraft has conducted radio science experiments at X-band and Ka-band to study the nature of Jupiter’s gravity field, study the Io plasma torus, and measure electron density profiles of the ionospheres of both Ganymede and Europa. On 31 July and 9 September 2023, the geometry of Juno’s orbit will enable the first radio occultation studies of the Jovian ionosphere and neutral atmosphere, conducted in more than 20 years. The first experiment (Perijove 53) involves a “grazing” occultation extending from latitudes 32.4 N down to 20.4 N. Because of the grazing geometry of the occultation, the maximum depth of the occultation corresponds approximately to the 150 mbar level of the atmosphere, with a corresponding ray bending angle of approximately 0.25 degrees, allowing conduct of the experiment without requiring pointing offsets for the high-gain antenna (HGA).

The Juno radio occultation experiments are conducted using an uplink frequency of 7.153 GHz (X-band), which serve to stabilize the two downlink signals at 8.404 (X-band) and 32.088 GHz (Ka-band). Measurements of both doppler shifts and signal intensities are being conducted. Differences in the percentage doppler shifts between X-band and Ka-band downlinks are used to retrieve electron densities in the ionosphere, whereas the combined X-band uplink and downlink doppler shifts are used to retrieve density profiles (related to temperature and pressure) in the neutral atmosphere.

This work was supported by NASA under support for the Juno Mission Science team member.

Comments
0
comment
No comments here