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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

IUS/TUG Orbital Operations and Mission Support Study: Executive Summary - Volume 1

The space transportation system (STS) is discussed which will include a propulsive stage that is carried into low earth orbit by the space shuttle. Data were accumulated from the analyses of various stage concepts, operating modes, and projected missions (space tug systems studies, growth stage studies, engine studies, and critical area studies). The foundation formulated by these studies aided in establishing a tentative two-phase approach for the extension of the STS operating regime beyond the space shuttle including plane changes, higher orbits, geosynchronous orbits and beyond. The orbital operations study, was conducted to provide the generation and analysis of operational plans, requirement, and concepts for the utilization of these vehicles. Primary emphasis was placed on methods and techniques to provide a sound technical approach to operations at reduced cost for the STS mission period.

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NASA NTRS1991

A space parasol as a countermeasure against the greenhouse effect

It is suggested that the deployment of a 'space parasol' at the L1 Langrangian point of the earth-sun system would serve to intercept some desired fraction of the solar radiant energy, thereby lessening the impact of the greenhouse effect. The parasol satellites are described and possible orbit configurations are discussed. Orbital possibilities include Low Earth Orbit, Geosynchronous orbit, and L1 which appears to be the best option. Structural strength, control, and use of extraterrestrial material in the construction of the parasol are discussed.

Hudson, H. S.↗
NASA NTRS1992

Report of the Working Group on Space/Lunar Tradeoffs

The group discussed the advantages and disadvantages of five locations for an optical/infrared array: low-Earth orbit (LEO), Sun-synchronous Earth-orbit, geosynchronous orbit (GEO), Lagrangian points (L4 and L5), and the lunar surface. The factors affecting an array and our assessments of them are given and briefly discussed. In the discussions, two axioms are assumed: (1) Human expansion into space and to the Moon will occur; and (2) The Space Station will be constructed and operational. The major conclusion reached is that baselines of moderate size (greater than 300 m) are best done on the Moon and that large baselines (greater than 10 km) can be done only on the Moon. Three areas needing additional research were identified as follows. (1) Studies are needed on methods to steer long-baseline systems in orbit. This involves learning how to control free-flyers. It is not clear how the difficulty of control varies with orbital elevation. (2) More work is needed on the internal metrology of array systems, both orbital and lunar-surface systems.(3) We need to understand the radiation effects on detectors and electronics and learn how to mitigate them.

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NASA NTRS2019

Updating the Space Communications and Navigation (SCaN) Link Tool Executable Software to Version 5

NASA’s Space Communications and Navigation (SCaN) program is responsible for providing space communication channels in low Earth orbit, geosynchronous orbit, and deep space for a variety of space missions. The SCaN Link Tool is a standalone, executable, and personal computer (PC)-based software operated via a user interface, which provides NASA civil servants and contractors, as well as the public by way of the tool’s inclusion in the NASA Software Catalog, with in-depth satellite communications link analysis capability. Version 4 of the tool was built using PythonTM (Python Software Foundation) with the help of libraries such as NumPy and SciPy for numerical calculations, Matplotlib for graphical visualizations, and PyQt5 for the graphical user interface. It utilizes radiofrequency (RF) and optical communications link analysis calculations to give users the ability to input known link parameters and calculate select link performance outputs. With the development of the next-generation architecture for space satellite communications in the coming decade, NASA will benefit by having more in-depth communications link analysis tools at its disposal. The tool’s update from version 4 to version 5 aims to provide higher output value accuracy, the ability to solve for a more diverse set of output variables, as well as analog and digital repeater capabilities. Options included in the tool’s functionality, such as the ability to save configuration parameter values, graphs, and results, as well as the provision of default parameter values, increase the tool’s versatility. Users will have access to in-depth, accurate communications link analysis as more advanced satellite constellations are designed and deployed by NASA and the growing commercial aerospace community.

Green, Jack L.↗
NASA NTRS1981

Electrostatic antenna space environment interaction study

The interactions of the electrostatic antenna with the space environment in both low Earth orbit and geosynchronous orbit are investigated. It is concluded that the electrostatically controlled membrane mirror is a viable concept for space applications. However, great care must be taken to enclose the high voltage electrodes in a Faraday cage structure to separate the high voltage region from the ambient plasma. For this reason, metallized cloth is not acceptable as a membrane material. Conventional spacecraft charging at geosynchronous orbit should not be a problem provided ancillary structures (such as booms) are given nonnegligible conductivity and adequate grounding. Power loss due to plasma electrons entering the high field region is a potentially serious problem. In low earth orbit any opening whatever in the Faraday cage is likely to produce an unacceptable power drain.

Katz, I.↗
NASA NTRS1977

Solar power satellite. System definition study. Part 1, volume 5: SPS transportation. Representative system descriptions

Both LEO transportation (earth to low earth orbit) and GEO transportation (low earth orbit to geosynchronous orbit) segments were addressed. LEO options include both a 2 stage winged space freighter vehicle and a 2 stage ballistic recoverable vehicle. Both incorporate LO(2)/RP-1/LH(2) engines on the booster and standard SSME's on the upper stage. The orbit transfer vehicle options included chemical for geosynchronous satellite assembly and self powered electric propulsion for low earth orbit satellite assembly. An exhaust products analysis was conducted for the earth to LEO vehicle since atmospheric pollution could be a concern.

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NASA NTRS1972

Earth orbit navigation study. Volume 2: System evaluation

An overall systems evaluation was made of five candidate navigation systems in support of earth orbit missions. The five systems were horizon sensor system, unkown landmark tracking system, ground transponder system, manned space flight network, and tracking and data relay satellite system. Two reference missions were chosen: a low earth orbit mission and a transfer trajectory mission from low earth orbit to geosynchronous orbit. The specific areas addressed in the evaluation were performance, multifunction utilization, system mechanization, and cost.

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NASA NTRS1973

Space tug.

The reusable space tug is a major system being planned for use with the space shuttle to augment its capability to deliver, retrieve, and support automated payloads. The reusable space tug will be designed to support all the planned missions beyond low earth orbit including geosynchronous orbit. Tug missions and requirements are discussed together with tug options, giving attention to existing transfer stages and growth stages. System studies for an interim tug concept are planned to begin in February 1973. Three independent studies will be conducted: two on cryogenic tugs and one on storable propellant tugs.-

Huber, W. G.↗
NASA NTRS1973

Earth-orbit mission considerations and Space Tug requirements.

The reusable Space Tug is a major system planned to augment the Space Shuttle's capability to deliver, retrieve, and support automated payloads. The Space Tug will be designed to perform round-trip missions from low earth orbit to geosynchronous orbit. Space Tug goals and requirements are discussed together with the characteristics of the full capability Tug. The Tug is to be operated in an unmanned 'teleoperator' fashion. Details of potential teleoperator applications are considered, giving attention to related systems studies, candidate Tug mission applications, Tug 'end-effector' alternatives, technical issues associated with Tug payload retrieval, and Tug/payload accommodations.

Huber, W. G.↗
NASA NTRS1977

Coordinated NASA nickel-cadmium battery technology program

This paper describes the NASA nickel-cadmium (Ni-Cd) battery technology program which is being coordinated by JPL to provide NASA and other users with lighter and/or longer-lived Ni-Cd cells for low-earth-orbit, geosynchronous-orbit, and planetary spacecraft missions in the 1980s. The goal is to double the energy density and/or life of the system. Failure modes and mechanisms are differentiated and discussed to point out the critical design variables which affect Ni-Cd cell life. Cell component weights are listed, approaches for reducing weight are discussed, and program tasks and schedules are presented. The nine major tasks being worked on by various organizations are described. Progress has been made in weight reduction, understanding of life reliability mechanisms, and development of a process for manufacturing more stable electrodes. An accelerated and predictive life test program is approximately 30% complete. It appears feasible to double the life and/or usable energy density of the Ni-Cd cell.

Bogner, R. S.↗
NASA NTRS1979

Spacecraft Charging Technology, 1978

The interaction of the aerospace environment with spacecraft surfaces and onboard, high voltage spacecraft systems operating over a wide range of altitudes from low Earth orbit to geosynchronous orbit is considered. Emphasis is placed on control of spacecraft electric potential. Electron and ion beams, plasma neutralizers material selection, and magnetic shielding are among the topics discussed.

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NASA NTRS1979

Large space system - Charged particle environment interaction technology

Large high-voltage space power systems proposed for future applications in both low earth orbit and geosynchronous altitudes must operate in the space charged-particle environment with possible interactions between this environment and the high-voltage surfaces. The paper reviews the ground experimental work to provide indicators for the interactions that could exist in the space power system. A preliminary analytical model of a large space power system is constructed using the existing NASA Charging Analyzer Program, and its performance in geosynchronous orbit is evaluated. The analytical results are used to illustrate the regions where detrimental interactions could exist and to establish areas where future technology is required.

Stevens, N. J.↗
NASA NTRS1980

Analysis of GaAs and Si solar cell arrays for earth orbital and orbit transfer missions

Silicon and gallium arsenide arrays were studied and compared for low earth orbit (LE), geosynchronous orbit (GEO), and LEO to GEO electric propulsion orbit transfer missions. The sensitivities of total cost to parameters such as mission duration, array cost, cover glass thickness, and concentration ratio were determined along with cost tradeoffs between silicon and gallium arsenide arrays for selected mission classes. Results indicate that development of the technology for low cost, light weight concentrators should be increased and that cost reduction efforts for gallium arsenide cells be pursued.

Jeffries, K. D.↗
NASA NTRS1980

Satellite power system (SPS) concept definition study. Volume 3: Experimental verification definition

An evolutionary Satellite Power Systems development plan was prepared. Planning analysis was directed toward the evolution of a scenario that met the stated objectives, was technically possible and economically attractive, and took into account constraining considerations, such as requirements for very large scale end-to-end demonstration in a compressed time frame, the relative cost/technical merits of ground testing versus space testing, and the need for large mass flow capability to low Earth orbit and geosynchronous orbit at reasonable cost per pound.

Hanley, G. M.↗
NASA NTRS1979

Structural design of free-flying solar-reflecting satellites

A promising spacecraft configuration for utilizing solar radiation is the large flat mirror. Very thin membranes with a reflective coating can be stretched to form such a mirror; the mirror mass density can therefore be very small. The purpose of the presentation is to examine the fundamentals of providing structural support for a free-flying membrane mirror. The objective of the examination is to determine what the masses of the structure might be to support membranes of areas from thousands to millions of square meters operating at altitudes from low-earth orbit to geosynchronous orbit.

Hedgepeth, J. M.↗
NASA NTRS1981

The electric rail gun for space propulsion

An analytic feasibility investigation of an electric propulsion concept for space application is described. In this concept, quasistatic thrust due to inertial reaction to repetitively accelerated pellets by an electric rail gun is used to propel a spacecraft. The study encompasses the major subsystems required in an electric rail gun propulsion system. The mass, performance, and configuration of each subsystem are described. Based on an analytic model of the system mass and performance, the electric rail gun mission performance as a reusable orbital transfer vehicle (OTV) is analyzed and compared to a 30 cm ion thruster system (BIMOD) and a chemical propulsion system (IUS) for payloads with masses of 1150 kg and 2300 kg. For system power levels in the range from 25 kW(e) to 100 kW(e) an electric rail gun OTV is more attractive than a BIMOD system for low Earth orbit to geosynchronous orbit transfer durations in the range from 20 to 120 days.

Bauer, D. P.↗
NASA NTRS1984

OTV propulsion tecnology programmatic overview

An advanced orbit transfer vehicles (OTV) which will be an integral part of the national space transportation system to carry men and cargo between low Earth orbit and geosynchronous orbit will perform planetary transfers and deliver large acceleration limited space structures to high Earth orbits is reviewed. The establishment of an advanced propulsion technology base for an OTV for the mid 1990's is outlined. The program supports technology for three unique engine concepts. Work is conducted to generic technologies which benefit all three concepts and specific technology which benefits only one of the concepts. Concept and technology definitions to identify propulsion innovations, and subcomponent research to explore and validate their potential benefits are included.

Cooper, L. P.↗