International Space Station Alpha Research Articles

The effect of microgravity on the composition of SHS products of the mixture NiO + Ni + Al + WC

The structure formation of the liquid-phase products of the synthesis of the model SHS mixture of the thermite type NiO + Ni + Al under microgravity conditions aboard the International Space Station ALPHA is investigated. Comparative investigations of the microstructure and chemical and phase compositions of synthesis products formed on the Earth and under microgravity conditions are performed. In the process of terrestrial experiments, the main attention was paid to the search for optimal compositions capable of burning under reduced pressure with a minimal spread of combustion products.

Initial transient in Zn-doped InSb grown in microgravity

Three Zn-doped InSb crystals were directionally solidified under microgravity conditions at the International Space Station (ISS) Alpha. The distribution of the Zn was measured using SIMS. A short diffusion-controlled transient, typical for systems with k >1 was demonstrated. Static pressure of ∼4000N/m2 was imposed on the melt, to prevent bubble formation and de-wetting. Still, partial de-wetting has occurred in one experiment, and apparently has disturbed the diffusive transport of Zn in the melt.

Antideuterons as a signature of supersymmetric dark matter

Once the energy spectrum of the secondary component is well understood, measurements of the antiproton cosmic-ray flux at Earth will be a powerful way to indirectly probe for the existence of supersymmetric relics in the galactic halo. Unfortunately, it is still spoiled by considerable theoretical uncertainties. As shown in this work, searches for low-energy antideuterons appear in the meantime as a plausible alternative, worth being explored. Above a few $\mathrm{GeV}/n,$ a dozen spallation antideuterons should be collected by the future Alpha Magnetic Spectrometer experiment on board International Space Station Alpha. For energies less than $\ensuremath{\sim}3\mathrm{GeV}/n,$ the $\overline{D}$ spallation component becomes negligible and may be supplanted by a potential supersymmetric signal. If a few low-energy antideuterons are discovered, this should be seriously taken as a clue for the existence of massive neutralinos in the Milky Way.

The Alpha Magnetic Spectrometer Silicon Tracker

The Alpha Magnetic Spectrometer (AMS) is designed as a independent module for installation on the International Space Station Alpha (ISSA) in the year 2002 for an operational period of three years. The principal scientific objectives are the searches for antimatter and dark matter in cosmic rays. The AMS uses 5.5 m2 of silicon microstrip sensors to reconstruct charged particle trajectories in the field of a permanent magnet. The detector design and construction covered a 3 yr period which terminated with a test flight on the NASA space shuttle Discovery during June 2–12, 1988. In this contribution, we describe the shuttle version of the AMS silicon tracker, including preliminary results of the tracker performance during the flight.

The ALPHA Magnetic Spectrometer

The ALPHA Magnetic Spectrometer (AMS) will be the first large magnetic spectrometer in space. It is scheduled to be installed on the future International Space Station ALPHA (ISSA) in the year 2002 to perform measurements of the charged particle composition to answer fundamental questions in particle physics and astrophysics. Before installation on ISSA, AMS will fly on the shuttle DISCOVERY for a period of 10 days starting in May 1998. This will enable AMS to perform a test of the apparatus and first measurements. The AMS detector has five major components: A permanent NdFeB magnet, six planes of Silicon double-sided microstrip detectors, a plastic scintillator time of flight hodoscope, a plastic scintillator anticoincidence counter and an Aerogel Cherenkov threshold counter. In addition, there are electronics, support infrastructure and interfaces.

Antimatter and dark mattersearch with the alpha magneticspectrometer (AMS)

Abstract The Alpha Magnetic Spectrometer (AMS) is the first large acceptance magnetic spectrometer to perform a long term search of antimatter and dark matter in space. The current theoretical view on antimatter and dark matter and the experimental status of the searchers are reviewed. The AMS detector and its performance during a precursor flight on the shuttle and the main mission on the International Space Station Alpha are described.

Calibration of the SOLSPEC spectrometer to measure the solar irradiance from space

The SOLSPEC instrument has been built to carry out absolute solar spectral irradiance measurements from space. It was first flown in December 1983 on mission STS 9 (Spacelab 1), from August 1992 to June 1993 on board the free-flying EURECA platform with mission STS 46 (deployment) and STS 57 (retrieval), then flown three times more with the ATLAS missions STS 45, 56 and 66. Further applications are foreseen in combination with the International Space Station Alpha (ISSA). SOLSPEC covers a wavelength range from 180 nm to 3000 nm split into three separate spectrometer channels (ultraviolet, visible and infrared) and has been calibrated pre- and post-flight using a black body at the Landessternwarte Heidelberg with temperatures up to 3300 K. In this paper the calibration concept is presented, together with a short instrument description and suggestions for improvements in order that higher black-body temperatures can be reached.

MEDES clinical research facility as a tool to prepare ISSA space flights

This new multi-disciplinary medical experimentation center provides the ideal scientific, medical and technical environment required for research programs and to prepare international space station Alpha (ISSA) missions, where space and healthcare industries can share their expertise. Different models are available to simulate space flight effects (bed-rest, confinement,…). This is of particular interest for research in Human psychology, physiology, physiopathology and ergonomics, validation of biomedical materials and procedures, testing of drugs, and other healthcare related products. This clinical research facility (CRF) provides valuable services in various fields of Human research requiring healthy volunteers. CRF is widely accessible to national and international, scientific, medical and industrial organisations. Furthermore, users have at their disposal the multi-disciplinary skills of MEDES staff and all MEDES partners on a single site.

Project of conveyer-type space greenhouse for cosmonauts' supply with vitamin greenery

Design and advantages of conveyer-type growth chamber PHYTOCYCLE with a cylindrical crop surface are featured. Based on the results of testing, an experimental prototype of conveyer-type vegetable greenhouse VITACYCLE for space vehicles is being developed at the SSC-IBMP in conjunction with a number of institutions of the Russian space industry to provide space crews with fresh greenery. Rated daily production of the greenhouse is 150 g of eatable biomass with power consumption of 1 kW. The system is to be mounted within the life support module of international space station Alpha (ISSA). Design of the greenhouse is outlined. Brief description, state-of-the-art, and further plans regarding VITACYCLE elaboration and construction are presented.

Empirical hole size and crack length models for dual-wall systems under hypervelocity projectile impact

This paper presents the results of a study whose objective was to develop empirical equations to characterize the hole formation and cracking phenomena associated with the penetration of some of the multi-wall systems being considered for the International Space Station Alpha. The significance of the work performed is that these equations can be used in a survivability analysis to determine whether or not module unzipping would occur under a specific set of impact conditions and the time available for module evacuation prior to the onset of incapacitation due to air loss. The correlation coefficients for the equations obtained exceeded 0.8 in most cases; hence, it is believed that the equations developed have a rather good fit to the experimental data.

The large silicon tracker for the AMS experiment on the International Space Station Alpha (ISSA)

The design of the high precision microstrip silicon tracker for the Alpha Magnetic Spectrometer experiment (AMS) is presented. We emphasize features of the silicon tracker which make it suitable for a space born experiment and for equipping large active areas.

Dynamics and control of multibody systems: An approach with application

The paper focuses on the study of the dynamics and control of large flexible space structures, comprised of sub-assemblies, a subject of considerable contemporary interest. To begin with, a relatively general Lagrangian formulation of the problem is developed. The governing equations are non-linear, non-autonomous, coupled and extremely lengthy even in matrix notation. Next, an efficient computer code is developed and the versatility of the program illustrated through a study of the dynamics of the First Element Launch (FEL) configuration of the Space Station Freedom, now superseded by the International Space Station Alpha. The response of the FEL is obtained for two critical disturbances: (a) docking of the Space Shuttle; and (b) maneuver of the onboard mobile manipulator system (MSS). The study clearly demonstrates a need for active control. To that end, robust control of the rigid body motion of the FEL configuration using the LQG LTR procedure is demonstrated. The controller designed using the simplified linear model, proves to be effective in regulating librational disturbances. Such a global approach—formulation, numerical code, dynamics and control—can serve as a powerful tool to gain comprehensive understanding of the interactions of the dynamics and thus aid in the development of effective and efficient control systems.

Design properties for state-of-the-art thermal control materials for manned space vehicles in LEO

Literature reports on spacecraft thermal control coatings generally emphasize changes in nominal properties after exposure to one or more of the space environments. Few have addressed the coating variability caused by normal processing tolerances and the variability at the end-of-life after environmental exposure in orbit. For critical thermal designs, this information is required by the thermal designer. The purpose of this paper was to collect design information used for conducting thermal analyses for the thermal control coatings used by Product Group 1 of the International Space Station Alpha. Both nominal values and manufacturing tolerances are listed for the beginning-of-life and for the end-of-life of the coating. In assessing the end-of-life values, McDonnell Douglas Aerospace (MDA) took into account contaminant deposition on the coatings and the influence of the natural environments on the deposited contamination layer. Because of the eroding effects of atomic oxygen on organic materials, most coatings selected were inorganic, including Z-93, conversion coatings, anodic coatings, and metal tubing with and without plating. Silicone-based paints and silverized Teflon were used for a few specific applications. This paper provides design information and tables for each of the coating categories defined and can serve as a convenient design reference for the thermal designer.

Improvement of the extravehicular activity suit for the MIR orbiting station program

Since 1977, EVA suits of the semi-rigid type have been used to support sorties from Russian orbiting stations. Currently, within the MIR station program, the Orlan-DMA, the latest modification of the Orlan semi-rigid EVA suit is used by crewmembers. Quite some experience has been gained by Russia in operations of the Orlan type suits. It has proved the advantages of the EVA suit of a semi-rigid configuration, featuring donning/doffing through a hinged backpack door with a built-in life support system. Meanwhile there were some wishes and comments from the crewmembers addressed to the enclosure design and some LSS components. Currently a number of ways and methods are being developed to improve operational characteristics of the suit as well as to enhance its reliability and lifetime. The forthcoming EVAs to be performed by the STS-MIR crewmembers and future EVAs from the common airlock of the International Space Station Alpha make implementation of the planned improvements even more consistent. The paper analyzes the experience gained in the Orlan-DMA operation and discusses planned improvements in light of the forthcoming activities. In particular the Orlan enhancement program is aimed to make the donning/doffing easier, enhance enclosure mobility, improve the condensate removal unit, increase the CCC (Contamination Control Cartridge) operation time and simplify the onboard subsystem design concept.

Numerical simulation of iodine speciation in relation to water disinfection aboard manned spacecraft I. Equilibria.

Elemental iodine (I2) is currently used as the drinking water disinfectant aboard the Shuttle Orbiter and will also be incorporated into the water recovery and distribution system for the International Space Station Alpha. Controlled release of I2 is achieved using the Microbial Check Valve (MCV), a flow-through device containing an iodinated polymer which imparts a bacteriostatic residual concentration of approximately 2mg/L to the aqueous stream. During regeneration of MCV canisters, I2 concentrations of approximately 300 mg/L are used. Dissolved iodine undergoes a series of hydrolytic disproportionation and related reactions which result in the formation of an array of inorganic species including: I-, I3-, HOI, OI-, IO3-, HIO3, I2OH-, I2O(-2), and H2OI+. Numerical estimation of the steady-state distribution of inorganic iodine containing species in pure water at 25 degrees C has been achieved by simultaneous solution of the multiple equilibrium expressions as a function of pH. The results are reported herein.

Integrated Risk Assessment: A Case Study

AbstractThe customer was the project manager for a research facility that is to fly on the International Space Station Alpha. The facility consists of two racks, plant and animal research units, and the associated ground and support systems.

Mini pressurized logistics module (MPLM)

The MPLM Program was initiated through a Memorandum of Understanding (MOU) between the United States' National Aeronautics and Space Administration (NASA) and Italy's ASI, the Italian Space Agency, that was signed on 6 December 1991. The MPLM is a pressurized logistics module that will be used to transport supplies and materials (up to 20,000 lb), including user experiments, between Earth and International Space Station Alpha (ISSA) using the Shuttle, to support active and passive storage, and to provide a habitable environment for two people when docked to the Station. The Italian Space Agency has selected Alenia Spazio to develop MPLM modules that have always been considered a key element for the new International Space Station taking benefit from its design flexibility and consequent possible cost saving based on the maximum utilization of the Shuttle launch capability for any mission. In the frame of the very recent agreement between the U.S. and Russia for cooperation in space, that foresees the utilization of MIR 1 hardware, the Italian MPLM will remain an important element of the logistics system, being the only pressurized module designed for re-entry. Within the new scenario of anticipated Shuttle flights to MIR 1 during Space Station phase 1, MPLM remains a candidate for one or more missions to provide MIR 1 resupply capabilities and advanced ISSA hardware/procedures verification. Based on the concept of Flexible Carriers, Alenia Spazio is providing NASA with three MPLM flight units that can be configured according to the requirements of the Human-Tended Capability (HTC) and Permanent Human Capability (PHC) of the Space Station. Configurability will allow transportation of passive cargo only, or a combination of passive and cold cargo accommodated in R/F racks. Having developed and qualified the baseline configuration with respect to the worst enveloping condition, each unit could be easily configured to the passive or active version depending upon the ISSA logistics requirements and their optimized fulfillment.

A silicon tracker for the anti matter spectrometer on the international space station ALPHA

We present the design of the Silicon Spectrometer for the AMS experiment on the International Space Station ALPHA. We review the design principles and some of the issues related to the construction of a large, high precison silicon microstip tracker for a space born experiment.

A Silicon Tracker for the Anti Matter Spectrometer on the International Space Station ALPHA

We present the design of the Silicon Spectrometer for the AMS experiment on the International Space Station ALPHA. We review the design principles and some of the issues related to the construction of a large, high precison silicon microstip tracker for a space born experiment.

Multicultural Human Factors Concerns aboard the International Space Station Alpha

As we enter the 21st century, we can expect an increase of international spaceflight missions made up of crew members from different cultures. This study assesses the potential effects of cultural and interpersonal communication factors on crew interaction and crew operations for multicultural spaceflight crews. During international missions, crew members from different countries will be living and working together within the confined and isolated quarters of their spacecraft. On many International Space Station Alpha missions, a crew will consist of Canadian, European, Japanese, and U.S. personnel. Mission duration can range from 90 to 180 days for International Space Station Alpha and approximately two years for a round-trip manned mission to Mars. Effective and efficient multicultural crew interaction and operations will assume a major role in flight safety and mission success. By means of a questionnaire and personal interviews, information was gathered, indicating cultural characteristics considered to be most relevant for future spacefarers from the various nations involved in future International Space Station Alpha missions.