CONSERT

CONSERT (Comet Nucleus Sounding Experiment by Radio wave Transmission) is a time domain transponder that operates between one module on the orbiter and another on the Philae lander.

 
A radio signal is transmitted from the orbiting component of the instrument and passes through the comet nucleus to the component on the comet surface. The signal is received on the lander, where some data are extracted, and then immediately re-transmitted back to the orbiter, where the main experiment data collection occurs. The loss of energy experienced by the radio signal, as well as the change in velocity caused by its passing through different materials can be used to give information regarding the internal structure of the comet’s nucleus.
 

CONSERT antenna

CONSERT antenna. Copyright ESA/AOES Medialab

 Sources and further information:

 http://sci.esa.int/rosetta/35061-instruments/?fbodylongid=1637