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This paper discusses the Inukshuk landed rover mission to Mars that is currently undergoing the Phase 0 mission study for the Canadian Space Agency. The Inukshuk landed rover mission addresses key science themes for planetary exploration; focusing on the search for hydrated mineralogy and subsurface water sites that can provide evidence of past or present life. New exploration and science will be accomplished using an innovative tethered combination of a small rover and a self-elevating sky-cam aerostat. The elevating visible (VIS) imager, at about 10 m altitude, will provide an informative high-resolution 2-D view of the rover below and surrounding terrain to greatly assist the semi-autonomous navigation of the rover around obstacles and selection of sites for detailed subsurface exploration.

This paper describes a new approach to spacecraft thermal control based on a passive thin-film smart radiator device (SRD) that employs a variable heat-transfer/emitter structure. The SRD employs an integrated thin-film structure based on V1-x-yMxNyOn that can be applied to existing Al thermal radiators. The SRD operates passively in response to changes in the temperature of the space structure. The V1-x-yMxNyOn exhibits a metal/insulator transition with temperature, varying from an IR transmissive insulating state at lower temperatures, to a semiconducting state at higher temperatures. Dopants, M and N, are employed to tailor the thermo-optic characteristics and the transition temperature of the passive SRD. The transition temperature can be preset over a wide range from below -30°C to above 68°C using suitable dopants. A proprietary SRD structure has been developed that facilitates emissivities below 0.2 to dark space at lower temperatures to reduce heater requirements.

Infrared (IR) spectroscopy probes the characteristic vibrational and rotational modes of chemical bonds in molecules to provide direct information about both the chemical composition and the bonding configuration of a sample. The significant advantage of the IR spectral technique is that it can be used with minimal consumables to simultaneously detect a large variety of different chemical and biochemical species with high chemical specificity. Currently, various VIS/NIR grating spectrometers are employed to cover the spectral range between 0.3 and about 2.2 (μm. Bulk-optic Fourier Transform (FT)-IR spectrometers employing variations of the Michelson interferometer are generally used to provide spectral measurements above 2.5 (μm. The FT-IR systems tend to be mechanically complex, bulky (>15 kg), and require considerable processing, maintenance and recalibration. For space-based systems, the important drivers are reliability, power consumption, mass and simplicity of operation.

Heat pipes, loop heat pipes and capillary pumped loops are heat transfer devices driven by capillary forces with high-effectiveness & performance, offering high-reliability & flexibility in varying g-environments. They are suitable for spacecraft thermal control where the mass, volume, and power budgets are very limited. The Canadian Space Agency is developing loop heat pipe hardware aimed at understanding the thermal performance of two-phase heat transfer devices and in developing numerical simulation techniques using thermo-hydraulic mathematical models, to enable development of novel thermal control technologies. This loop heat pipe consists of a cylindrical evaporator, compensation chamber, condenser along with vapor and liquid lines, which can be easily assembled/disassembled for test purposes. This laboratory setup is especially designed to enable the visualization of fluid flow and phase change phenomena.

The paper addresses the thermal control of a lunar lander/rover by use of heat pumps enabling payload heat to be rejected at a higher temperature to the lunar day environment. The heat pump technologies considered include absorption, vapor compression, adsorption, hybrid and chemical heat pumps technologies. A trade-off of the various heat pump technologies for a 2kW payload cooling capability is presented based on the needs of space-based hardware in terms of low mass and power, high performance, reliability and compactness of the systems. Finally the selection of a novel variant of the chemical heat pump concept is presented as a promising technology to be further investigated through breadboard development.

The thermal control of lunar landers/rovers necessitates the use of a system to allow heat rejection to the high temperature lunar environment. In this context a vapour compression heat pump which is a proven technology in terrestrial and aeronautical applications has been studied; its suitability in providing 2 kW cooling capability with adequate temperature lift for final heat rejection by space radiators is assessed. The stringent requirements of space-based hardware in terms of temperature lift, compactness, mass, performance and reliability necessitates optimization studies. Mass optimization of the heat pump components has been carried out, as well as selection of refrigerants and thermodynamic cycles most suited for the application.

Manned space systems have many requirements for the monitoring of vital life support systems including quality of cabin air and the recycled water supply, as well as direct monitoring of vital indicators of astronaut health. Infrared (IR) spectroscopy is an attractive monitoring technique because it requires minimal consumables while providing relatively high chemical specificity for the detection of a wide variety of biochemicals using the characteristic vibrational modes of chemical bonds. For space-based systems, the important drivers are reliability, power consumption, mass and simplicity of operation. MPB has advanced its IOSPEC™ technology for miniature integrated IR spectrometers to provide performance comparable to large bench-top IR systems but in a compact and ruggedized footprint weighing under 2.5 kg.