These two plots where built with data retrieved from ASPERA, the Analyzer of Space Plasma and Energetic Atoms on board ESA’s Venus Express, on 30 May 2006, when the spacecraft was flying through different domains of the interaction region between Venus and the solar wind.
The X axis of the plots provides the different position at which the ions (charged atoms) hit the ASPERA detectors. The Y axis provides the energy of the detected ions. The white lines correspond to different ion masses.
The left plot shows the heated solar wind (protons and ‘alfa-particles’) which just passed the Venus bow shock (the region in space separating the unperturbed solar wind from the area where the solar wind interacts with the planetary environment). The right plot shows massive escape of the planetary oxygen ions detected inside the solar wind void which results from the interaction with Venus.