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The objective o f the NASA JPL Space Technology 7 -Disturbance Reduction System (ST7-DRS) mission is to demonstrate: (I) test mass trajectory control that deviates from purely gravitational trajectory by less than 3~1 0 . '~ ~n / s e c~/ H z~~~ [l+(V3 mHz)*] over a frequency range from 1 mHz to 30 mHz and (2) spacecraft position control within l O n m / H~~.~ over the same frequency range. To achieve these objectives, two technologies must be advanced and tightly integrated. These technologies are the Gravitational Reference Sensors (GRS) being developed by Stanford University and the Colloid Micro-Thruster (CMT) propulsion system in development at Busek Co. Inc. The DRS system will he integrated by JPL and fly on an ESA spacecraft called the LISA Pathfmder. This paper reports on the progress in the propulsion technology area.The 1O:l dynamic thrust range, the continuous thrust adjustability and noise requirements represent unique challenges that require significant advances in several technology areas, including extremely precise propellant flow control (

Dilute concentrations of l,l,l-trichloroethane (TCA) in air were decomposed in an electron beam generated plasma reactor. The energy required for high levels of TCA decomposition (greater than 90%) was determined as a function of inlet concentration. For 99% decomposition of TCA, e~ 300 eV/molecule at 250 ppm inlet concentration, and e~ lOO eV/molecule at 3000ppm. A radical reaction mechanism is proposed which accounts for the formation of the major reaction products." 1,1-dichloroethylene, HCI, chloroacetylchloride, CO,,, and COC12. A model is derived based on first-order inhibited kinetics: a fit of the data to the model shows that at high decomposition fractions, radical scavenging by reaction products is a significant inhibitor of TCA decomposition.