The temperature sensor on the Huygens probe for the Cassini mission: design, manufacture, calibration and tests of the laboratory prototype

A platinum resistance thermemeter will be used to determine the vertical temperature profile of the Titan lower atmosphere. The sensor is part of the HASI (Huygens Atmospheric Structure Instrument) which will be located on the Huygens probe for the Cassini mission. The design and manufacture of a laboratory prototype have made it possible to verify calibration and test procedures appropriate to the flight units. The sensor has been selected and evaluated with great care in order to ensure performance within the mission requirements which demand accuracy and resolution of 0.5 and 0.02 K, respectively. The calibration and test results confirm performance within the design goals. Further results, dealing with mechanical characterizations aimed at verifying the sensorʹs capability to withstand launch, entry and descent conditions, are also presented.