Hubble observation of aurorae on Ganymede
The NASA/ESA Hubble Space Telescope has observed a pair of auroral belts encircling the Jovian moon Ganymede. The belts were observed in ultraviolet light by the Space Telescope Imaging Spectrograph and are coloured blue in this illustration.
They are overlaid on a visible-light image of Ganymede taken by NASA's Galileo orbiter. The locations of the glowing aurorae are determined by the moon's magnetic field, and therefore provide a probe of the moon's interior, where the magnetic field is generated. The amount of rocking of the magnetic field, caused by its interaction with Jupiter's own immense magnetosphere, provides evidence that the moon has a subsurface ocean of saline water.
Links:
- NASA press release
- Artist's illustration of aurorae and Ganymede
- Ganymede's magnetic field
- Plot of the rocking of Ganymede's magnetic field
- Cutaway of the Moon Ganymede
NASA, ESA, and J. Saur (University of Cologne, Germany)
About the Image
About the Object
Name: | Ganymede |
Type: | Solar System : Planet : Satellite |
Category: | Solar System |