1. Electric Propulsion System Setup S 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 10 11 From PCDU S/C Communication 9 9 Xenon System Thermal System Power / Intercomm 0.2 m No redundancies, no integration costs

2. Electric Propulsion System Specifications Specifications for the Hall Thruster – 100g Mission VariableValueUnits Thrust78.5mN Specific Impulse1950s Mass Flow Rate4.1mg/s Power Input1526W Efficiency0.53-- Input Voltage350VDC Mass5.7kg Propulsion System Totals – 10kg Mission VariableValueUnits Wet Mass215kg Dry Mass30kg Required Power2,043Watts Burn time365days Thrust104mN Specific Impulse1964s Mass flow Rate5.4mg/s Specifications for the BHT-8000 Hall Thruster – Large Mission VariableValueUnits Thrust424mN Specific Impulse2250s Mass Flow Rate19.2mg/s Power Input7,600W Efficiency0.64-- Mass25kg Propulsion System Totals - Large Mission VariableValueUnits Wet Mass3,810kg Dry Mass520kg Required Power38,773Watts Burn time365days Payload Capability4,545kg

3. LOx/LH2 would require an extra 600 kg, costing an extra $2.6M An ion thruster could accomplish the mission, but would require much more power than the HET Current technology places HET lifetime over 1 year Other Propulsion Options

4. Xenon Storage Thermal Analysis Allowed temperature path of propellant Maximize storage pressure for volume efficiency (~ 150 bar) Maintain tank temperature for gaseous Xenon phase:  Balance heat due to radiation and pressure drop with a 5 watt resistance heater Curve data from National Institute of Standards and Technology Temperature (K)