Thermal conductivity instrument for measuring planetary atmospheric properties and data analysis technique

Abstract

This paper outlines the method of measurement and analysis of the thermal conductivity instrument (THP) that has successfully returned measurements from the atmosphere of Saturn’s moon Titan during the descent of the Huygens probe on 14^th January 2005.

The technique is validated by analysing laboratory calibration data gathered by our instrument in three pure gases (nitrogen, methane, and ethane) over Titan’s temperature range (90 to 180 K). Calibration results show errors <1% compared to reference values when processed using this method.

Details included here along with references should serve as a useful guide for interpreting data from thermal conductivity instruments for space or other stand alone applications for fluids over various pressure and temperature ranges. Our calibration only verifies measurements over Titan conditions, although [4] suggests that the validity of this method extends up to 400 atmospheres and 800°C.