Microwave dielectric constant of Titan-relevant materials

For four years, the Cassini Radar instrument has slowly revealed the surface of Titan. It has discovered cryovolcanic flows, craters, dunes, channels, rivers, lakes and seas. In order to analyze and model the microwave behaviour of Titan's surface, we need to know the dielectric constant of its surface materials. We present here Ku-band (10 and 13 GHz) measurements of the dielectric constant of various materials that are likely to be present on Titan. Most of the measured values are in the 1.5-4.3 range with a very low loss tangent (less than 10(-2)), consistent with results obtained from the Radar scatterometer and radiometer modes, indicating that the Cassini Ku-band Radar should penetrate several meters of Titan's surface.