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The Phoenix Mars Lander is scheduled to be launched in August 2007 and will land in the northern Vastitas Borealis region. The lander is equipped with a suite of instruments designed to investigate the mineralogy and geochemistry of the soil and to study the atmosphere. The Canadian Meteorological Instrument (MET) will measure the location and the extent of clouds and the distribution of scatterers in the atmosphere as well as measuring the air temperature and the barometric pressure. The MET will provide Canadian scientists with a unique opportunity to study the Martian atmosphere and enhance our understanding of the planet in key areas of Canadian expertise. The MET instrument is composed of multiple elements in order to fulfil the science objectives. The MET Light Imaging Detection and Ranging (LIDAR) will probe the atmosphere by sending out laser pulses and measuring the backscattered returns.

This work presents the results of an experimental High Performance Miniature Loop Heat Pipe. The evaporator utilizes a wick structure with the non-inverted meniscus evaporation concept, which allows using high thermal conductivity materials for the evaporator case and capillary wick structure, and hence will further reduce the thermal resistance between the evaporator elements. The heat fluxes at the evaporator can therefore be significantly higher than that of a LHP using inverted meniscus evaporation approach. Tests were conducted in the Material and Thermal Laboratory at the Canadian Space Agency. The evaporator heat input cross-section area was 2.4 cm2. When water is used as the working liquid the heat transfer rate has reached values as high as 215W, corresponding to a heat flux density of 90W/cm2 (temperature drop between heat source and LHP evaporator was ∼7°C). Working temperature oscillations (with amplitude ∼2-10°C) were observed for steady state regimes of LHP operation.

Spacecraft attitude control provides the basic stability so that sensors, solar panels, antennas and other hardware are properly oriented to perform their functions. A Horizon scanner can automatically seek the earth horizon by detecting the sharp discontinuity in InfraRed intensity at the outer edge of the Earth's mesopause for purposes of a spacecraft's orientation and control. As a satellite in a Low Earth Orbit (LEO) and three-axis stabilized, the Canadian satellite RADARSAT-1 is equipped with two horizon scanners (HS) in order to scan dynamically across the Earth's disc and to establish the attitude relative to the Earth. This paper discusses the thermal design and analyzes the on-orbit thermal performance of the HS.

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.

This paper describes the thermal design, analysis and test 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 Electro Magnetic 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).