Artist’s Concept of Aurorae and Ganymede

This is an artist's concept of the moon Ganymede as it orbits the giant planet Jupiter. NASA's Hubble Space Telescope observed aurorae on the moon that are controlled by Ganymede's magnetic fields. Two auroral ovals can be seen over northern and southern mid-latitudes. Hubble measured slight shifts in the auroral belts due to the influence of Jupiter's own immense magnetic field. This activity allows for a probe of the moon's interior. The presence of a saline ocean under the moon's icy crust reduces the shifting of the ovals as measured by Hubble. As on Earth, Ganymede's aurorae are produced by energetic charged particles causing gases to fluoresce.

About the data

The image was created from Hubble data from the following proposal: 12244 PI: J. Saur (University of Cologne, Germany), P. Feldman and D. Strobel (JHU), K. Retherford (SwRI), M. McGrath (NASA/MSFC), and S. Duling (University of Cologne, Germany).

The science team includes: J. Saur and S. Duling (University of Cologne, Germany), L. Roth (SwRI/University of Cologne, Germany), D. Strobel and P. Feldman (JHU), U. Christensen (Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany), K. Retherford (SwRI), M. McGrath (NASA/MSFC), F. Musacchio, A. Wennmacher, and F. Neubauer (University of Cologne, Germany), and S. Simon (Georgia Institute of Technology, Atlanta), and O. Hartkorn (University of Cologne, Germany).