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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.

Nanofluids have been recently investigated as new working media for two-phase thermal control systems. However, conflicting reports have emerged, in which contradictory effects of the nanoparticles on the working performance of heat pipes have been described. Some studies have shown that gold or silver nanoparticles significantly improve heat transfer performances of heat pipes. Other studies have provided evidence that metal nanoparticles have no particular effect. This study is aimed at determining whether nanofluids are good candidates as heat carriers in a Loop Heat Pipe (LHP) system. Here, a nanofluid consisting of well-characterized citrate-stabilized gold nanoparticles in water is examined. The metallic nanoparticles are functionalized with citrate ligands in order to be soluble and stable in water at room temperature. An LHP hardware set-up was developed for this investigation.

Manned space systems have many requirements for the monitoring of vital life support systems such as the cabin air quality and the quality of the recycled water supply. Infrared spectroscopy probes the characteristic vibrational and rotational modes of chemical bonds in molecules to provide 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 chemical and biochemical species with high chemical specificity. To date, relatively large Fourier Transform (FT-IR) spectrometers employing variations of the Michelson interferometer have been successfully employed in space for various IR spectroscopy applications. However, FT-IR systems are mechanically complex, bulky (> 15 kg), and require considerable processing.

This paper describes the thermal design and analysis of the Electronic Unit (EU) of a Microgravity Vibration Isolation System (MVIS) that will ensure the active isolation of the European Space Agency's Fluid Science Laboratory (FSL) payload from vibration induced by the International Space Station (ISS) structure. The FSL is equipped with optical and electronic devices that are very sensitive to vibration, thermal distortion, temperature change and ElectroMagnetic Interference (EMI). The MVIS has to provide a vibration attenuation of -40dB within the range of 0.1-100Hz without inducing thermal or electromagnetic interferences. The sensitive FSL instruments are mounted in a floating structure called the Facility Core Element (FCE), whereas the rest of the FSL electronics, mechanics and cooling systems are fixed to the International Standard Payload Rack (ISPR).

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.