Aurora at Ganymede

Ganymede´s intrinsic magnetic field generates a small magnetosphere inside Jupiter´s magnetosphere.

Magnetospheric processes cause auroral light emissions at Ganymede, which has been observed by the Hubble Space Telescope.

It is from these auroral emission lines that we know the atmosphere is dominated by molecular oxygen.The aurora is an integral part of the coupling between the ionosphere and the magnetosphere; it has been used to draw conclusions about the interior of Ganymede as well as about its atmosphere. The knowledge obtained will advance our understanding of aurora in general, not only on Ganymede.

Furthermore, this auroral research will impact several fields of Ganymede studies, including surface weathering and atmosphere formation.Our team is experienced in Vlasov simulations of aurora at Earth.

We will build on this experience, using a Vlasov simulation code to model the plasma on an auroral field line at Ganymede. This will tell us where and how the electrons that cause the aurora are accelerated.

In addition to the Vlasov simulations, we will use hybrid simulations to constrain the boundary conditions of the field line.

Our team is experienced in hybrid simulations as well as photo-chemical modelling of Ganymede and of the physics of Jupiter´s magnetosphere.This work will form a necessary modelling background to analysis of data from ESA´s JUpiter ICy moon Explorer (JUICE) mission which will be orbiting Ganymede, Jupiter´s largest moon, for 9 months.