EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

The two faces of the Jovian UV aurorae

Bertrand Bonfond1, Denis Grodent1, Benjamin Palmaerts1, Randy Gladstone2, Sarah Badman3, John Clarke4, Jean-Claude Gérard1, Rohini Giles2, Thomas Greathouse2, Kamolporn Haewsantati1,5, Vincent Hue2, Joshua Kammer2, Jonathan Nichols6, Guillaume Sicorello1, Suwicha Wannawichian5, and Zhonghua Yao7,1
Bertrand Bonfond et al.
  • 1Université de Liège, STAR Institute, Liège, Belgium (
  • 2Southwest Research Institute, San Antonio, USA
  • 3Lancaster University, Lancaster, United Kingdom
  • 4Boston University, Boston, USA
  • 5Chiang Mai University, Chiang Mai, Thaïland
  • 6University of Leicester, Leicester, United Kingdom
  • 7Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China

Being mostly connected via closed magnetic field lines, the aurorae at the two poles display two broadly similar signatures of the same magnetospheric processes. However, differences are sometimes observed, indicative of asymmetries either in the polar regions (e.g. different solar illumination, magnetic anomalies, etc.) or in the magnetosphere (e.g. twisting of the magnetotail), thus showing two complementary sides of the magnetosphere-ionosphere coupling.

Whatever the planet, seeing the aurorae on both poles at the same time is challenging. Either both polar regions can be seen at once, but then only from the side, with poor spatial coverage (especially close and beyond the limb), or we need (at least) two observatories. Here we use the latter option to observe the two faces of the UV aurorae on Jupiter. In the last years, several Hubble Space Telescope observations with the Space Telescope Imaging Spectrograph (STIS) have been planned during close-up perijove observations of the poles with the UV spectrograph (UVS) on board the Juno spacecraft. The aurorae at Jupiter can be divided into three main components, with the Main Emissions, a quasi-continuous, but sometimes irregular, ribbon of auroral emissions, delimitating the outer emissions outside of it and the polar emissions inside of it. We compare the global morphology and the relative power emitted by the different auroral features in these three regions. Former studies also indicated that synchronized quasi-periodic flares could be observed in both hemispheres and we will look after similar events in this new dataset. Finally, even if the observations are delayed by approximately one hour, we can still compare the mean emitted power before (north) and after (south) each Juno perijove to look for a global trend.

How to cite: Bonfond, B., Grodent, D., Palmaerts, B., Gladstone, R., Badman, S., Clarke, J., Gérard, J.-C., Giles, R., Greathouse, T., Haewsantati, K., Hue, V., Kammer, J., Nichols, J., Sicorello, G., Wannawichian, S., and Yao, Z.: The two faces of the Jovian UV aurorae, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-5947,, 2022.


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