PDS_VERSION_ID = PDS3 LABEL_REVISION_NOTE = "2015-07-08, initial release" RECORD_TYPE = STREAM OBJECT = INSTRUMENT INSTRUMENT_HOST_ID = "RL" INSTRUMENT_ID = "MUPUS" OBJECT = INSTRUMENT_INFORMATION INSTRUMENT_NAME ="MULTI PURPOSE SUITE FOR SURFACE AND SUBSURFACE SCIENCE" INSTRUMENT_TYPE = "ACCELEROMETER" /* RLC was + "PENETROMETER THERMAL PROBE","INFRARED RADIOMETER" */ INSTRUMENT_DESC = " Instrument Overview =================== Multi Purpose Suite for Surface and Subsurface Science (MUPUS) is part of the Philae instrument payload. It consists of a Penetrator (PEN) which is equipped with 16 thermal sensors, the infrared radiometer (TM), and thermal (ANC-T) and accelerometer sensors /ANC-M) located in the Philae harpoons. Scientific Objectives ===================== The scientific goals of MUPUS are: - to determine the energy balance of the comets surface and its variation with time and depth - to determine the thermal conductivity of the comet down to a depth of 32 cm - to determine the thermal inertia of the surface - to determine the strength of the cometary surface layers Calibration =========== Due to problems with the ground calibration the PEN sensors were re-calibrated in flight by comparison with a h/k Pt-100 located on the holder the penetrator tube. The TM radiometer was calibrated in the Space simulator at DLR Berlin using an LN2 cooled low temperature blackbody. The calibrated temperature range was 120-270 K. TM is further equipped with an inflight calibration device (a cylindrical blackbody which covers a small part of the FOV which can be heated up to 400 K). Inflight calibration runs performed during cruise have revealed a significant degradation compared to the ground calibration (suffered already on Earth !). Therefore, the final calibration of TM was done using the deep space view during the descent of Philae to the comet. Operational Considerations ========================== The sensor heads PENEL and TM are both equipped with a front-end-electronics which require a certain minimum switch-on temperature (-50 deg for PEN and -90 deg for TM). Therefore, a warm-up heating phase controlled by the MUPUS DPU is required before these sensor heads can be switched on. Detectors ========= MUPUS comprises of three sensors: a cylindrical Penetrator tube with a length of ~ 35 cm and a diameter of 1 cm which is equipped with 16 RTD-type thermal sensors made by sputtering Titan on a Kapton foil. The sensors can also serve as heaters for acctive thermal conductivity measurements; an infrared radiometer equipped with 4 thermopile detectors and the necessary reference temperature sensors realized by miniature Pt-1000; the Philae harpoons which are each equipped with a Pt-100 temperature sensor and an accelerometer working at a sampling frequence of 48 kHz. More details are found in Spohn et.al, 2007 Electronics =========== Details on the electronics of the instrument are described in Spohn, et.al, 2007. ======== MUPUS PEN is mounted on the Lander balcony attached to its deployment device (DD) during cruise. After landing on the comet the DD will be used to deploy PEN up to a maximum distance of 1 m from the balcony. TM is mounted on the V-strut on the balcony close to the CIVA-St camera and below the Tx/Rx antennas. The harpoons are located below the Lander baseplate and may penetrate up to 2 m depth after the shot. The MUPUS central electronics is located inside the warm compartment of Philae. Operational Modes ================= MUPUS can be operated in several different different modes. The main mode is TEM which performs temperature measurements using all MUPUS thermal sensors (PEN, TM, ANC-T) in regular time intervals. A similar mode but without measuring the PEN sensors is MAPPER which should be used if the PEN is not deployed. The third thermal mode of the instrument is THC which performs an active thermal conductivity measurement using a (configurable) number of PEN sensors for heating. Further operational modes are ARM (deploying the PEN), HAMMER (inserting PEN into the ground), and ANCHOR (fast sampling of the accelerometers in the harpoons after the shot). Subsystems ========== The sub-systems are described in Spohn et al, 2007. Measured Parameters =================== Measured parameters are temperatures for PEN and ANC-T, brightness temperatures which are equivalent to infrared net fluxes for TM, and acceleration for ANC-M. " END_OBJECT = INSTRUMENT_INFORMATION OBJECT = INSTRUMENT_REFERENCE_INFO REFERENCE_KEY_ID ="SPOHNETAL2007" END_OBJECT = INSTRUMENT_REFERENCE_INFO END_OBJECT = INSTRUMENT END