Chandra Long-Exposure Observations of Jupiter’s X-ray Auroral Emissions Near Juno Apojove 2021
- 1School of Cosmic Physics, DIAS Dunsink Observatory, Dublin Institute for Advanced Studies, Dublin 15, Ireland
- 2School of Physics, Trinity College Dublin, Dublin, Ireland
- 3Department of Physics and Astronomy, University College London, London, UK
- 4Centre for Planetary Sciences at UCL/Birkbeck, London, UK
- 5LESIA, Observatoire de Paris, CNRS, PSL Research University, Meudon, France
- 6Space Research Corporation, Annapolis, MD
- 7Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa, USA
- 8Harvard-Smithsonian Center for Astrophysics, Smithsonian Astrophysical Observatory, Cambridge, MA, USA
- 9Mullard Space Science Laboratory, Department of Space and Climate Physics, University College London, Dorking, UK
- 10Space Science and Engineering Division, Southwest Research Institute, San Antonio, TX, USA
- 11Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX, USA
In this study we analyse a 40 hour (~ 4 jovian rotation) Chandra X-ray observation beginning on 15 September 2021 in order to study the morphology and time variability of the auroral X-ray emissions at Jupiter. At the time of this observation, Juno's orbit had taken the spacecraft into the dusk magnetosphere of Jupiter, thought to be the most likely source region for driving of jovian auroral X-rays. One leading theory for the driver of these emissions is Ultra Low Frequency (ULF) waves propagating along jovian magnetic field lines which can be initiated by processes on the dusk flank of the magnetosphere. This was the first time that this region had been observed by an orbiter since Galileo > 20 years ago, and never before has there been contemporaneous in situ and X-ray observations here. The long exposure time of this observation enables monitoring of the auroral regions over multiple jovian rotations, which is key to understand how variable the X-ray emissions can be. This allows for the identification of short timescale changes in the magnetospheric dynamics. Wavelet transforms and Rayleigh testing are used to search for statistically significant quasi-periodic pulsations of the X-ray emissions in the dataset. We combine the remote X-ray analysis with examination of data from the Juno Waves instrument, which has already shown that quasi-periodic emissions in the radio waveband can change on timescales of a few hours. Furthermore, we incorporate data from the Juno MAG instrument to provide magnetospheric context over the duration of the Chandra X-ray observation, and identify a possible compression event in the second half of the 40 hour time window. The Tao et al. (2005) solar wind propagation model also suggests a disturbed/compressed magnetosphere at this time, which is further supported by comparing the measured magnetic field against the baseline Kivelson and Khurana (2002) lobe magnetic field model.
How to cite: McEntee, S., Jackman, C., Weigt, D., Louis, C., Dunn, W., Boudouma, A., Connerney, J., Kurth, W., Kraft, R., Branduardi-Raymont, G., and Gladstone, R.: Chandra Long-Exposure Observations of Jupiter’s X-ray Auroral Emissions Near Juno Apojove 2021, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-17176, https://doi.org/10.5194/egusphere-egu23-17176, 2023.
