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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.

As the construction of an International Space Station approaches reality, the next phases in the exploration of Space will require long duration missions to the Moon, Mars, and beyond. The risk of traumatic injury and death will be an ever present factor in near space (within our solar system). Reviews of trauma deaths have consistently found that the greatest reduction in preventable death will occur by addressing definitive airway management, treatment of hemothorax and pneumothorax, and control of intra-abdominal hemorrhage. On a long duration space voyage realistic capabilities exist to potentially manage the first two injuries of this triad. The ability to manage a patient requiring operative control of an abdominal injury represents a quantum leap in commitment, but provides a new standard to target in surgical support of the ongoing exploration of space.

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.

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).

The Canadian RADARSAT-1 has successfully served the world as an earth observation satellite since Nov 1995. In this paper, the thermal performance of RADARSAT-1 over the 5 ears on orbit (Nov 1995–Nov 2000) has been analyzed through the telemetry temperature data. Analysis has been performed for the overall spacecraft, the subsystems and some selected units. The thermal control system of the RADARSAT-1 has been examined for cases of both normal orbital conditions and abnormal thermal environments and operations. The TCS has satisfactorily served RADARSAT-1 for a variety of thermal operations. The phenomenon of thermal-optical surface degradation has been directly observed from the thermal data, and varying behaviour of surface degradation has been detected.

Cryogenic cooling of infra red detectors is a well know requirement and need for many instruments in space application. The need for higher performance and long-life cryogenic cooling system, along with already stringent requirements for vibration, compactness, and mass, is self evident in spacecraft instruments especially for long space missions. It is therefore an object of this study to provide a system that has the potential to meet these challenges. A new absorption based cryocooler is presented and studied. Different absorption working fluids are selected and studied. Thermodynamic state performance and major items of the design specifications are described and presented. The main characteristics of the absorption system in this study are the lowest temperature that could be reached in the evaporator side and the nature of the working fluid mixture. A maximum of 100 W cooling capacity in the evaporator side is considered.

The System for Monitoring and Maintaining MRO Performance (SMP) is a new Canadian payload on board the ISS since February 2003. It is designed to investigate the effects of long-term space flight on Mobile Servicing System Robotics Operator (MRO) skill degradation and recovery. SMP consists of a Space Station Remote Manipulator System (SSRMS) simulator running on a laptop computer which takes its input from a pair of hand controllers. The first prototype of SMP simulates the capture of a payload that is hovering in space next to the ISS. This task has been identified as the most complex MRO hand controlled operation. The SMP also contains an innovative software module that automatically evaluates and quantifies the performance level of a particular operator. Based on that evaluation, the system can make a recommendation on whether or not the MRO needs additional training to reach a satisfactory skill level.

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).

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.

Two-Phase Loops with Capillary Pump (Loop Heat Pipes (LHP) and Capillary Pumped Loops (CPL)) are currently among advanced thermal control technologies for aerospace applications. Large numbers of experimental and operational two-phase loops were successfully tested and used in several spacecraft in the past two decades. Novel technologies such as Advanced CPL-LHP, High Performance CPL, miniature LHPs, inversion (reversible, “Push-Pull") LHPs, ramified, multiple evaporator and condenser LHPs and CPLs, for complex thermal control systems are being proposed. This paper presents a state-of-the-art survey and analysis of these technologies. A classification of Two-Phase Loop with Capillary Pump designs is recommended. Basic principles, operational conditions and characteristics, temperature control and start-up initiation are discussed. The use of thermal control systems based on Two-Phase Loops with Capillary Pump for space applications is reviewed and summarized.