1. IWF Graz … 1 Report at Midterm Meeting April 11 2006 Meltingprobe Midterm Meeting: 11-04-2006 Development of a melting probe for Mars and Europa Norbert I. Kömle Project overview

2. IWF Graz … 2 Scientific Goals Meltingprobe Midterm Meeting: 11-04-2006 Explore vertical layering of deep ice sheets under low pressure conditions  Composition  Texture  Dust content  Traces of organics Reconstruct geological history and climate evolution of planetary bodies  Thermal properties  Optical properties  Electrical properties  Density  Pressure Geocryology for icy moons and planets

3. Overview Meltingprobe Midterm Meeting: 11-04-2006 Administration Characterization of targets Scientific requirements Technical requirements Payload candidates

4. IWF Graz … 4 Administration Meltingprobe Midterm Meeting: 11-04-2006 September 06 2005Kickoff Meeting IWF Graz November 2005 ESTEC contract signed by all parties (ÖAW, ESTEC) Dr. Erika Kaufmann 100 % working contract funded from project (current funding period: 12 months) November 2005 - April 2006 Draft documents created: TARGET CHARACTERIZATION, SCIENTIFIC REQUIREMENTS AND PAYLOAD CANDIDATES MECHANICAL AND THERMAL DESIGN ELECTRONICS DESIGN February 06 2006First melting test in vacuum with existing probe April 11 2005Midterm Meeting IWF Graz

5. IWF Graz … 5 Targets diameter6794 km mass0.108 M E solar distance1.52 AU max. solar radiation591 W/m 2 gravitational acceleration 0.38 g Meltingprobe Midterm Meeting: 11-04-2006 MARS EUROPA diameter3138 km mass0.008 M E solar distance5.20 AU max. solar radiation51 W/m 2 gravitational acceleration 0.134 g

6. IWF Graz … 6 Target description: MARS Polar Areas Meltingprobe Midterm Meeting: 11-04-2006 North perennial ice cap South perennial ice cap

7. IWF Graz … 7 Target description: EUROPA 1 Meltingprobe Midterm Meeting: 11-04-2006 Interior structure

8. IWF Graz … 8 Target description: EUROPA 2 Meltingprobe Midterm Meeting: 11-04-2006 Triple bands and ice cracks

9. IWF Graz … 9 Target description: EUROPA 3 Meltingprobe Midterm Meeting: 11-04-2006 Suspicion: Around ice cracks ice layer may be thin Access to subsurface ocean by means of a melting probe?

10. IWF Graz … 10 Technical requirements for first prototype Meltingprobe Midterm Meeting: 11-04-2006  Use of standard components for electronics: Cross section not too small, chosen dimensions: diameter 6 cm, length 20 cm  Length of tether: ca. 30 m (long enough to test functionality of tether deployment and internal power dissipation  Power supply: 28V, 70W maximum (to avoid use of high voltage components in laboratory testing  Payload: Simple strawman payload, A/D conversion of sensor data inside probe and data transfer through power cable

11. IWF Graz … 11 Payload Candidates Meltingprobe Midterm Meeting: 11-04-2006 Temperature sensors housekeeping and natural temperature profile during non- heating periods (evaluation of thermal properties) Tilt sensors housekeeping (reconstruct path of probe in the ice) ISFET chemical sensors PH-value of meltwater, trace elements Miniature mass spectrometer (Open University) elemental composition Miniature TOF mass spectrometer (Physikalisches Institut, Uni Bern) elemental composition CBD-densitometer (Open University) material density around by measuring Compton backscattering of a gamma source Optical/IR sensors albedo variations along melt path as indicator for contaminations

12. IWF Graz … 12 Present status of prototype construction Meltingprobe Midterm Meeting: 11-04-2006 ItemStatus Mechanical design drawingsready Electronics designunder consideration, partially ready Mechanical parts for prototypeordered Electronics parts for prototypeordered, partially available Components for tetherpartially available Heater foils (MINCO)available PT100 sensors (MINCO)available ADXL tilt sensoravailable ISFET PH sensoravailable

13. IWF Graz … 13 First melting test at IWF: 06-02-2006 Meltingprobe Midterm Meeting: 11-04-2006 Temperature evolution of different parts of melting probe and ice sample during the experiment

14. IWF Graz … 14 Test results Meltingprobe Midterm Meeting: 11-04-2006 Heating power: 60 W Ice temperature: -30°C Hot tip temperature when in contact with ice: 30°C Hot tip temperature after loss of ice contact: > 130°C Temperature of probe rear end (still outside ice): 80°C  Power of 70 W appropriate for 6 cm cross section  Launch pad must be improved  Rear end may become too hot as long as probe not fully inside ice Lessons from test: