Artist's impression of Boom 2 deployed

This is an impression of how the first two stages of deployment look for the Mars Express MARSIS experiment. The 13 segments of the first 20-metre boom have sprung out and locked into place, followed by the second 20-metre boom.

The MARSIS experiment will map the Martian sub-surface structure to a depth of a few kilometres. The instrument's 40-metre long antenna booms will send low frequency radio waves towards the planet, which will be reflected from any surface they encounter.