9612538 Kenny This proposal describes an effort to develop a Micromachined Calorimeter for the NASA/JPL New Millennium Spacecraft Program. This device will be used to study effects of the ion engine exhaust plume on passive infrared radiators used to release heat from the spacecraft core and from science instruments. New Millennium is a technology validation program, and will provide a flight opportunity on the first Deep Space 1 (DS1). The performance of exposure calorimeters is improved through reduction of heat capacity and thermal conductance. Silicon Micromachining is ideally suited to this task, offering low-stress nitride membranes with well-characterized, thermal, mechanical, and optical characteristics. The expected characteristics of the Micromachined Calorimeter offer a significant performance improvement over conventionally-built calorimeters. ***
