1. THEMIS Instrument PDR 1 UCB, October 15-16, 2003 IDPU Mechanical / Thermal Preliminary Design Review Heath Bersch University of California - Berkeley

2. THEMIS Instrument PDR 2 UCB, October 15-16, 2003 IDPU Concept IDPU Chassis Concept MASS = 1800 GRAMS EMPTY 4MM WALLS PROVIDE SHIELDING ADDITIONAL SHIELDING PER BOARD AND SPACE CRAFT BUS Volume = 652 cubic centimeters

3. THEMIS Instrument PDR 3 UCB, October 15-16, 2003 ICD Drawing

4. THEMIS Instrument PDR 4 UCB, October 15-16, 2003 LVPSLVPS FGE/PCBFGE/PCB DCB/ETCDCB/ETC DFBDFB BEBBEB SSTSST Card Assignments

5. THEMIS Instrument PDR 5 UCB, October 15-16, 2003 ALUM SHIELD PEM SPACER HEAT SINKS WEDGE LOC D-SUB CONNECTOR Standard Card

6. THEMIS Instrument PDR 6 UCB, October 15-16, 2003 Wedge Loc Interface

7. THEMIS Instrument PDR 7 UCB, October 15-16, 2003 ESA Attachment Concept

8. THEMIS Instrument PDR 8 UCB, October 15-16, 2003 Thermal - IDPU Heat Transfer Power Dissipation 10.74 W Conduction We are trying to keep the bottom deck warm Therefore the IDPU is thermally coupled to the bottom deck using a ChoTherm gasket ESA conducts heat away and radiates it to space Radiation All surfaces covered with low ε VDA tape or blankets IDPU may need radiator, current Swales model includes one

9. THEMIS Instrument PDR 9 UCB, October 15-16, 2003 Thermal - IDPU Temperature Limits Predictions from Swales Cold prediction from 3 hour eclipse orbit Hot prediction from hottest orbit and attitude Average operating temperature around 30 °C Better predictions await more complete instrument thermal models Survival (°C) Predictions (°C) Margin (°C) Eclipse-Op Science-OpColdHotColdHot -50-3040+65-1636144

10. THEMIS Instrument PDR 10 UCB, October 15-16, 2003 Thermal - IDPU Temperature Monitoring and Control Modified Interface Monitoring Probe Bus will monitor the interface temperature near the IDPU Instrument Monitoring IDPU will process additional thermistors if needed Heaters No operational heaters are required Survival heaters will keep IDPU above Eclipse-Op Limits Two heater services provided by the probe bus Primary service thermostat closes at -23 Secondary service thermostat closes at –28 IDPU may share heater with the ESA, depends on final coupling