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The forthcoming planetary missions require an autonomous crew habitation and a high mass of metabolic consumables. To minimise the launch mass and/or the logistic needs, these missions shall then be based on regenerative technologies able to obtain resources for the human life from the on board produced wastes, guaranteeing a high closure degree of the system. In this context ESA has promoted a preliminary study called SpaceHaven, to understand which functions must be guaranteed for a long term and autonomous mission and to investigate about the hardware/technologies to be exploited to meet the identified functions. A dedicated demonstration program is to be proposed when needed technologies are neither available in Europe nor currently covered by a dedicated technological development.

Aim of the Closed Habitat Environmental Control Sensors (CHECS) project has been the setting up of a complete, lightweight sensing system for monitoring the ambient conditions of plant growth in space missions. A complete sensor system has been developed and tested, based on a deep knowledge of plant needs, and on the typical plant behaviour in stress conditions. The main characteristic of the system is its compatibility with Silicon technology. This means high integrability, reduced dimensions, low weight, redundancy, simplicity and high reliability. All the sensors composing the systems have been produced by means of well developed solid state technology, including the MicroSystem Technology (MST) and Porous Silicon Technology (PST). The latter has proved in the last year to have considerable advantages over other approaches.

This paper describes the thermal design and analysis of RADARSAT-2, a commercial Synthetic Aperture Radar (SAR) satellite for earth observation. The particular thermal design challenges faced by RADARSAT-2 are the continually varying thermal environment imposed by its dawn-dusk, sun-synchronous orbit and the wide range of operational capabilities of the SAR payload. The SAR antenna is a 15m active array design that incorporates 512 transmit/receive (T/R) modules distributed throughout the antenna panels. The thermal environment for these high-dissipation units must be maintained throughout the various mission configurations. The Bus and the Extendable Support Structure (ESS) which deploys and supports the SAR antenna must provide a thermoelastically stable platform from which to mount the SAR antenna as well as the attitude sensors.

The Total Off-gassing test purpose is to determine the identity and quantity of trace gas contaminants offgassed in areas of spacecraft where the crew will breathe the atmosphere. Two different air sampling methods were adopted in parallel during the off-gassing tests on the Multi-Purpose Logistics Modules (MPLM) by Alenia Spazio. The first method, based on NASA (National Aeronautics and Space Administration) requirements, foresees storage of collected air samples into stainless steel pressure cylinders. The second method proposed by ESA (European Space Agency), uses trace contaminants adsorption on Carbopack™ filled ceramic tubes. Sample lines route the samples collected inside the MPLM cabin, to the respective external collection points. Successively, the stored samples are chemically analyzed by Gas Chromatography / Mass Spectrometry (GC/MS) techniques and the module offgassing rates are calculated.

Space hardware design, as well as that for hardware destined to work in 1-g environment, needs to be submitted to a complete design verification process before final utilisation in nominal conditions. As space hardware ground verification is difficult and expensive, a design verification philosophy has been developed in order to reach, as far as possible, the highest degree of space hardware reliability and usability and hence to increase crew productivity via a perfect integration of man and machines. This activity is mainly based on a complete hardware testing process (first on ground, then in microgravity simulated environment and, at the end, during a short duration space mission) and on a correct test procedure preparation in order to avoid inconveniences during test execution. Opportunity for an application of the design verification philosophy has been given by Columbus Precursor Flights and the related MIRIAM '95 programme.

Microorganism accumulation and growth onboard a spacecraft may impact adversely on crew efficiency and safety as well as system, subsystems and payload. The results of test campaigns performed at Alenia Spazio in Summer 1993 are reported here. From them, some simple and effective prevention methods to be applied during the manufacturing and integration phases of a pressurised spacecraft have been identified and are here discussed. Although data obtained from Earth experience may be considered useful, it is uncertain and unfit for space station operational lifespan. Therefore, it is necessary to build a model of the phenomenon, able to provide a series of quantitative data as a function of different parameters related to environmental characteristics, crew, and on-board activities.

The Mini Pressurised Logistics Module (MPLM), a cooperative project between NASA and ASI that will be designed, developed, produced, integrated and delivered by Alenia, is a pressurised volume devoted to the resupply and return of Space Station (SS)containerized cargo requiringapressurised environment, via the National Space Transportation System (NSTS). As a servicer for the SS, the MPLM will have to accomplish several trips between Earth and SS in support of logistic needs. Since the active payloads launched with MPLM (freezers and refrigerators) require resources during the transportation phase inside the NSTS, the MPLM has the peculiar capacity to exchange power, data and fluids with the Orbiter before docking to SS. Once docked to SS, the MPLM will be required to provide its full performance, making use of the resources available from the SS Node; nevertheless, in this phase some of the MPLM functions are demanded from the SS.

The redesign of Space Station Freedom (SSF) and the requirement of the Columbus programme board to reduce costs have led ESA to change the design and development strategy of the Attached Pressurised Module (APM). A revised APM reference design for integration with the SSF Alpha has been produced with sufficient flexibility to allow adaptation as part of a global space station or to permit operations as part of a European Free Flyer. The main objectives of the redesign have been to simplify the design, reduce the costs and provide increased autonomy from the SSF. The key groundrules for the redesign have been an AR5/ATV launch from the Centre Spatial Guyanais (CGS) into an orbit inclined at 51.6 degrees. The APM has a length equivalent to 5 double racks and a net launch mass of 1200 kg. It will be delivered to the SSF at an altitude of 407 km for a 10-year operational life. Safe disposal will be by ATV.

In the overall planning of a manned mission to Mars, all the issues related to human involvement are critical. To a certain extent, they dictate the most severe constraints on the mission scenario and spacecraft architecture. Despite this unanimously recognized importance, limited efforts have been devoted up to now to dedicated research activities on human-related aspects, partially neglected w.r.t. more technical areas like orbital dynamics, propulsion, power generation, etc. This paper summarizes the major results of a survey on the human factors of long duration missions performed by Alenia Spazio in the frame of an ESA study, MARSEMSI, whose aim was to identify possible scenarios and related infrastructure requirements for a manned mission to Mars.