ASPERA-3: Energetic Neutral Atom Imaging
The co-existence of an energetic charged particle population (solar wind, magnetospheric plasma) and a planetary neutral gas leads to interaction, e.g., through charge-exchange:
In contrast to charged particles, ENAs are no longer influenced by electromagnetic fields and propagate on straight paths from the source to the observer. Directional detection of ENAs yields a global image of the interaction and by complex inversion techniques properties of the source populations can be deduced.
ENA production mechanisms in space plasmas comprise:
The IMAGE mission successfully proved that ENA imaging can provide global views of plasma processes (substorm particle injections, ring current distribution and dynamics) in the Earth's Magnetosphere.
The MIMI instrument on Cassini provided ENA images of the Jupiter - Io Torus system.
The simulated ASPERA-3 ENA response shows that the solar wind - exosphere interaction processes at Mars can be globally imaged in ENA.
|© 2006, Max Planck Institute for
Solar System Research, Lindau