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Followed by brief discussions of the primary natural particle radiation sources and the operational sensitivities imposed by them on crew and spacecraft, the analytical system and methods are described. The use of this automated analytical tool called Brem (Boeing radiation exposure model), is then addressed regarding spacecraft design and the optimization of radiation shielding. ...The use of this automated analytical tool called Brem (Boeing radiation exposure model), is then addressed regarding spacecraft design and the optimization of radiation shielding.

AFR, Inc. is developing a multifunctional Carbon material that, in addition to excellent radiation shielding characteristics, is appropriate for certain energy storage applications. As an excellent Hydrogen gas sorbent, it increases the usable storage capacity of a gas cylinder by ~25% at 3500 PSI and by ~150% at 500 PSI. Our recent NASA-Langley SBIR study shows that when a sorbent-filled tank is charged with hydrogen, it provides shielding superior to polyethylene against most types of ionizing particles. Even as hydrogen is consumed, the carbon and tank ensure that significant radiation shielding capability is maintained. Vastly improved radiation shielding is a clear requirement for a potential manned mission to Mars or a long-duration base on the surface of the Moon. However, current shielding technologies are predicated upon systems dedicated solely to the task of shielding.

This paper describes a new microcomputer-based program that evaluates the radiation shielding of spacecraft or Space Station modules. This program runs on a computer-aided design (CAD) system that constructs and manipulates models of spacecraft. ...This program runs on a computer-aided design (CAD) system that constructs and manipulates models of spacecraft. It uses the graphical and geometrical functions of the CAD system to analyse the radiation shielding provided by spacecraft models. ...It uses the graphical and geometrical functions of the CAD system to analyse the radiation shielding provided by spacecraft models. The program has the following new features: It uses solid angles of equal size that are distributed uniformly over a sphere surrounding the point of interest; It computes the geometrical intersection of each solid angle with a specified layer of a spacecraft model; It computes the volume, centroid and average thickness of each intersection, along with the variance of its volume and the standard error of its centroid position; It writes computer files of both the solid model and its volume, centroid and average thickness for each intersection for a given dose point and shielding layer.

Some of the more significant interactions between the radiator and vehicle of nuclear electric spacecraft are considered. This includes the selection of indirect versus direct condensing in the radiator; meteoroid armor and bumper criteria; booster constraints; aero shroud and structural integration; the significance of headers and feeds, electric transmission lines, and nuclear radiation shielding; and the magnitude of the structure contribution to system optimization.

The use of composite materials with high thermal conductivities is increasingly widespread in space flight applications. However, as opportunities for these new materials expand, practical limitations restrict their use. Some limitations are inherent in the composite materials themselves, like thermal conductivity and radiation shielding, and some are imposed by external design rules, like electro-magnetic interference (EMI) shielding and grounding. This paper reviews the work done at the Johns Hopkins University / Applied Physics Laboratory (JHU/APL) to quantify the thermal characteristics of high conductivity fiber/polymer matrix composites, to identify the other design constraints that limit their use, and the ongoing effort to reduce those limitations.

Major improvements have been completed in the approach to analyses and simulation of spacecraft radiation shielding and exposure. A Computer-Aided Design (CAD)-based system has been developed for determining the amount of shielding provided by a spacecraft and simulating transmission of an incident radiation environment to any point within or external to the vehicle. ...A Computer-Aided Design (CAD)-based system has been developed for determining the amount of shielding provided by a spacecraft and simulating transmission of an incident radiation environment to any point within or external to the vehicle.

Current spacesuit life support systems use consumable absorbents for carbon dioxide and odor control, condensing heat exchangers and high-speed rotary separators for humidity control, and easily-contaminated water-ice sublimators for waste heat removal, resulting in complex hardware with high consumables/power usage and maintenance. The Mobile Liquid Venting Membrane Separator (VMS) performs these life support functions with low logistics penalties. It exploits pressure-swing absorption and temperature-controlled evaporation to transport carbon dioxide, humidity, odor, and waste heat to space vacuum. The Mobile Liquid VMS removes carbon dioxide, humidity, and odors from air by absorption into a hydrophilic liquid circulating around a solvent loop. Waste heat is transferred from thermal sources into the solvent loop through a heat exchanger.

This standard defines the requirements and characteristics of electrical power for spacecraft. This standard also defines analysis, verification, and testing methodologies to be used to ensure that the loads operate when connected to the specified power quality and performance as defined by this standard.

This does not include lasers onboard aircraft where the beam is contained within an enclosure so that the beam cannot enter into airspace, nor does it include lasers from satellites and spacecraft in outer space. It may be used in conjunction with: AS4970, ARP5535, ARP5572, ARP5293, and the ANSI Z136 laser safety standards.

Standard methods are being developed to measure abrasive wear on candidate construction materials to be used for spacesuits, spacecraft, and robotics. Calibration tests were conducted using a standard diamond stylus scratch tip on the common spacecraft structure aluminum, Al 6061-T6. ...Calibration tests were conducted using a standard diamond stylus scratch tip on the common spacecraft structure aluminum, Al 6061-T6. Custom tips were fabricated from terrestrial counterparts of lunar minerals for scratching Al 6061-T6 and comparing to standard diamond scratches.

The hazards of ionizing radiation in space continue to be a limiting factor in the design of spacecraft and habitats. Shielding against such hazards is an enabling technology in human and robotic exploration and development of space. ...A collaborative engineering environment can optimize ALL design parameters to cost and produce a spacecraft that will meet all mission requirements at the minimum cost. This paper will describe such an environment and how much has been implemented at LaRC, other NASA Centers, National Labs, and industry.

Integral black anodizing and gold plating on Mg-Li alloys were developed for spacecraft thermal control applications. The influence of various process conditions have been investigated to optimise the process. ...The gold coating on the other hand provides the infrared emittance as low as 0.03, is extremely suitable in minimising the radiative coupling with other components within the spacecraft. Such gold metallised surfaces with extremely low infrared emittance values are useful as radiation shields for achieving temperatures as low as 80°K in space application such as very high resolution radiometers.

Starting from REMSIM study for ESA, we are focusing on short and long term shielding experiments aboard ISS (ESCHILO, ALTCRISS, SOFOCLE) by comparing the materials used in inflatable structures with the typical rigid materials used in current spacecraft, and optimizing and validating the radiation shielding solutions in LEO. To assess shielding strategies, tests in flight are always supported by calculations and laboratory experiments.

In this paper we investigate the radiation-mitigation properties of several shielding materials for possible use in spacecraft design, surface habitats, surface rovers, spacesuits, and temporary shelters. A discussion of the space radiation environment is presented in detail.

The space radiation environment consists of geomagnetically trapped protons and electrons, galactic cosmic radiation, and at times, high-energy solar particles that can penetrate spacecraft and spacesuits to produce a significant radiation exposure to crewmembers. The International Space Station (ISS) era will find astronauts spending months at a time on orbit, will occur during the rise and peak of the current solar cycle, and the construction of the ISS will require astronauts to perform these tasks in thinly shielded spacesuits. ...In order to determine the astronaut radiation exposures and related health risks, computerized anatomical male and female models have been developed and are used in conjunction with models of the space radiation environment and spacecraft and spacesuit shielding models. The National Council on Radiation Protection and Measurements (NCRP) has identified several critical body organs that are at risk. ...In this paper, a review of the space radiation environment, spacecraft, and computerized anatomical models is discussed in detail. Results of a parametric study of body organ exposures from the trapped proton environment as a function of ISS module location, orbital altitude, and solar cycle conditions are presented.

In the study the incident radiation spectra are transported through the spacecraft structure/magnetic shield using the deterministic space radiation transport computer codes developed at Langley Research Center.

Topics discussed include the space radiation environment, analytical spacecraft and anatomical modelling techniques, radiation dose programs, mission support functions and objectives, flight instrumentation, and measurements.

Consisting of deterministic space radiation transport computer codes and accurate models of their nuclear interaction inputs, these calculational tools are employed to estimate the composition and thicknesses of candidate shield materials required for spacecraft equipment and crew protection. In this paper, the current status of model and code development is summarized, preliminary estimates of deep-space shield requirements are presented, and an assessment of radiation protection as a potential “showstopper” for manned deep-space missions will be made.

Configurations similar to ’V-Grooves’, as already applied for radiators, can also insulate complete spacecraft and telescopes from solar radiation or hot modules several orders of magnitude better than the usual MLI.

These flexible materials in general have poorly known space radiation properties, whose lack of characterisation propagates the uncertainty about the shielding efficiency against the radiation environment on the whole spacecraft protection means. The consequent evaluation of their shielding efficiency, as well as of that of the overall shields, is based on flight experiments performed in Low Earth Orbit (LEO), onboard the International Space Station (ISS) and the re-entry capsule Foton.