CONSERT (Comet Nucleus Sounding Experiment by Radiowave Transmission):

Probes the comet’s interior by studying radio waves that are reflected and scattered by the nucleus.

The Orbiter's scientific payload includes 11 experiments, in addition to the Lander. Scientific consortia from institutes across Europe and the United States have provided these state-of-the-art instruments. All of them are located on the side of the spacecraft that will permanently face the comet during the main scientific phase of the mission.