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A rotating spacecraft which encloses an atmospheric pressure vessel poses unique challenges for thermal control. In any given location, the artificial gravity vector is directed from the center to the periphery of the vehicle. Its local magnitude is determined by the mathematics of centripetal acceleration and is directly proportional to the radius at which the measurement is taken. Accordingly, we have a system with cylindrical symmetry, featuring microgravity at its core and increasingly strong gravity toward the periphery. The tendency for heat to move by convection toward the center of the craft is one consequence which must be addressed. In addition, fluid flow and thermal transfer is markedly different in this unique environment. Our strategy for thermal control represents a novel approach to address these constraints. We present data to theoretically and experimentally justify design decisions behind the Mars Gravity Biosatellite's proposed payload thermal control subassembly.

The first use of the Polar Platform (PPF) is for the Envisat/PPF mission. The Envisat/PPF spacecraft has a launch mass of 8.5 tons and external dimensions of 10.0 metres x 2.8 metres x 2.1 metres. Due to it's large size it was necessary to perform the thermal balance and thermal vacuum testing in two modules. The first test was for the Service Module (SM) and the second for the Payload Module (PLM). This paper discusses the thermal balance testing and subsequent correlation of the Polar Platform Service Module thermal mathematical model.

An increasing number of spacecraft missions have very stringent requirements for thermal stability to avoid thermally driven noise from affecting the main observables. For example, it may be necessary to reduce temperature fluctuations in the neighbourhood of the instrument below micro-Kelvin (μK). Consequently, the influence of fluctuations in boundary temperature or internal power dissipation on temperature at the instrument detector must be precisely evaluated. Thermal stability requirements are usually expressed as an upper limit on the linear spectrum density (LSD) of temperature fluctuations. This indicates the strength of the response to a perturbation of a given frequency, and is usually stated in units of K/√Hz. The LSD can be estimated by running a succession of transient simulations and applying Fast Fourier Transforms techniques, but this method is time-consuming and has numerical limitations.

The Closed-Loop Air REvitalisation System ARES is a regenerative life support system for closed habitats. With regenerative processes the ARES covers the life support functions: 1. Removal of carbon dioxide from the spacecraft atmosphere via a regenerative adsorption/desorption process, 2. Supply of breathable oxygen via electrolysis of water, 3. Catalytic conversion of carbon dioxide with hydrogen to water and methane. ARES will be accommodated in a double ISPR Rack which will contain all main and support functions like power and data handling and process water management. It is foreseen to be installed onboard the International Space Station (ISS) in the Columbus Module in 2013. After an initial technology demonstration phase ARES shall continue to operate thus enhancing the capabilities of the ISS Life Support System as acknowledged by NASA [5]. Due to its regenerative processes ARES will allow a significant reduction of water upload to the ISS.

Determining the fundamental role of gravity in vital biological systems in space is one of six science and research areas that provides the philosophical underpinning for why NASA exists. The study of cells, tissues, and microorganisms in a spaceflight environment holds the promise of answering multiple intriguing questions about how gravity affects living systems. To enable these studies, specimens must be maintained in an environment similar to that used in a laboratory. Cell culture studies under normal laboratory conditions involve maintaining a highly specialized environment with the necessary temperature, humidity control, nutrient, and gas exchange conditions. These same cell life support conditions must be provided by the International Space Station (ISS) Cell Culture Unit (CCU) in the unique environment of space. The CCU is a perfusion-based system that must function in microgravity, at unit gravity (1g) on earth, and from 0.1g up to 2g aboard the ISS centrifuge rotor.

Neutral buoyancy (NB) and parabolic flight (PF) are the only available human-scale three-dimensional spaceflight simulation environments. As such, both environments are used extensively for both research and mission operations purposes despite a lack of quantitative (or even qualitative) characterization of the fidelity of either environment to the spacelfight analog. The present study was undertaken as part of a larger research effort to begin to build such characterizations. Eight healthy adults (4 men and 4 women) were asked to adopt relaxed postures while ‘standing’ in space shuttle middeck standard-type foot restraints, in NB and during the 0g periods of PF. Subjects were tested in NB in 9 orientations, 3 trials each: Upright; tilted 45° Front, 45° Back, 45° Right, 45° Left; and tilted 90° Front, Back, Right, and Left. PF limitations prohibited 90° testing; consequently the PF test protocol included only Upright and 45° orientations.

The Columbus Orbital Facility is being developed as the European laboratory contribution to the United States' led International Space Station programme. The need to exchange thermal mathematical models frequently amongst the Space Station partners for thermal analyses in support of their individual programme milestone, integration and verification activities requires the development of a commonly agreed and effective approach to identify and validate mathematical models and environments. The approach needs to take into account the fact that the partners have different model and software tool requirements and the fact that the models need to be properly tailored to include all the relevant design features. It must also decouple both programmes from the unavoidable design changes they are still undergoing. This problem presents itself for both active and passive thermal interfaces.

This paper describes recent advances in MPB's approach to spacecraft thermal control based on a passive thin-film smart radiator tile (SRT) that employs a variable heat-transfer/emitter structure. This can be applied to Al thermal radiators as a direct replacement for the existing OSR (optical second-reflector) radiator tiles with a net added mass under 100 gm/m2. The SRT employs a smart, integrated thin-film structure based on the nano-engineering of V1-x-yMxNyOn that facilitates thermal control by dynamically modifying the net infrared emittance passively in response to the temperature of the space structure. Dopants, M and N, are employed to tailor the transition temperature characteristics of the tuneable IR emittance. This facilitates thermal emissivities below 0.3 to dark space at lower temperatures that enhance the self-heating of the spacecraft to reduce heater requirements.

Future planetary extravehicular activities (EVAs) will go beyond what was experienced during Apollo. As mission duration becomes longer, inevitably, the astronauts on the surface of the Moon and Mars will actively plan and re-plan their own sorties. To design robust decision support aids for these activities, we have to first characterize all the different types of excursions that are possible. This paper describes a framework that organizes parameters and constraints that define a single planetary EVA. We arrived at this framework through case studies: by reviewing the EVA lessons learned during Apollo, conducting an observational study of excursions in a Mars-analog environment, and applying part of the framework to a prototype path planner for human planetary exploration.

Future human space exploration includes returning to the Moon and continuing to Mars. Essential to these missions is each planetary extravehicular activity, or EVA, where astronauts and robotic agents will explore lunar and planetary surfaces. Real-time decision support systems will help these explorers in efficiently planning and re-planning under time pressure sorties. Information and functional requirements for such a system are recommended and are based on on-going human-computer collaboration research.