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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 613 records · Page 34
All sourcesNASA NTRSDOE OSTI
NASA NTRS1992

Long Duration Exposure Facility (LDEF) preliminary findings: LEO space effects on the space plasma-voltage drainage experiment

The Space Plasma-High Voltage Drainage Experiment (SP-HVDE) provided a unique opportunity to study long term space environmental effects on materials because it was comprised of two identical experimental trays; one tray located on the ram facing side (D-10), and the other on the wake facing side (B-4) of the LDEF. This configuration allows for the comparison of identical materials exposed to two distinctly different environments. The purpose of this work is to document an assessment of the effects of five and three quarters years of low Earth orbital space exposure on materials comprising the SP-HVDE (experiment no. A0054). The findings of the materials investigation reported focus on atomic oxygen effects, micrometeor and debris impact site documentation, thermal property measurements, and environmentally induced contamination.

Blakkolb, Brian K.↗
NASA NTRS1992

Scattering effects of solar panel on Space Station Space-To-Ground (SGS) antenna performance

The purpose of this study is to characterize the scattering effects of a solar panel on the Space Station Space-to-Ground Subsystem reflector antenna when the antenna is operated in the RF tracking (difference) mode. This analysis is based on a combination of geometrical theory of diffraction and aperture integration techniques. The advantage of this combination method is its capability in predicting reflector antenna patterns not only in the forward region but also in the far-out sidelobes and backlobes. To verify the analytical model, measurements were performed on the Johnson Space Center far-field antenna test facility. Good agreement between computed and measured results was obtained. It was shown from computation and experiment that the solar panel scattering interference causes a shift in null position, a decrease in the depth of the null, as well as a decrease in the gain on the antenna difference mode patterns.

Hwu, Shian U.↗
NASA NTRS1992

Interaction dynamics of an orbiter and a flexible space structure undergoing incremental in-space construction

A theoretical investigation is presented pertaining to the use of a Shuttle based remote manipulator system to construct and assemble the Space Station at the primary stage. The equations of motion for an on-orbit Space Shuttle with flexible or rigid remote manipulator system are developed including the effect of librational motion, starting and stopping motion constraints, and contact/impact conditions in maneuvering the Space Shuttle Remote Manipulator System (SRMS). Preliminary results indicated that the orbiting system may become unstable when certain disturbances have been triggered that provided a guideline in maneuvering the SRMS.

Chiou, J. C.↗
NASA NTRS1992

Space Shuttle orbiter modifications to support Space Station Freedom

The modifications to the Space Shuttle orbiter required to support Space Station Freedom (SSF) assembly and operations are described. Attention is given to berthing modifications, Shuttle Remote Manipulator System upgrades, docking modifications, and Spacelab mission modifications. For SSF assembly missions, the Space Shuttle orbiter will transport elements of the SSF to a 28.5 deg inclination, 220 nm altitude (nominal) orbit.

Segert, Randall↗
NASA NTRS1992

Orbiting Space Interferometer (OSI): A first generation space interferometer

The technical requirements and performance of a first generation space interferometer is discussed. The performance of an interferometer, sensitivity, field of view, dynamic range, astrometric accuracy, etc, in space is set by what cannot be achieved for a ground-based instrument. For the Orbiting Space Interferometer (OSI), the nominal performance parameters are 20 mag sensitivity, field of view of approximately 500*500 pixels, a 1000:1 dynamic range in the image with one milliarcsec resolution, and an astrometric accuracy of 0.1 milliarcsec for wide angle astrometry and 10 microarcsec accuracy for narrow field astrometry (few degrees). OSI is a fully phased interferometer where all critical optical paths are controlled to 0.05 wavelengths. The instrument uses two guide interferometers locked on bright stars several degrees away to provide the spacecraft attitude information needed to keep the fringes from the faint science object stable on the detector.

Shao, Michael↗
NASA NTRS1992

Utilization of space resources in the space transportation system

Utilization of space resources (i.e., raw materials obtained from nonterrestrial sources) has often been cited as a prerequisite for large-scale industrialization and habitation of space. While transportation of extremely large quantities of material from Earth would be costly and potentially destructive to our environment, vast quantities of usable resources might be derived from the Moon, the asteroids, and other celestial objects in a cost-effective and environmentally benign manner. The primary purpose of the parametric cost model developed as part of this study is to identify the factors that have the greatest influence on the economics of space resource utilization. In the near term, this information can be used to devise strategies for technology development so that capabilities developed will produce cost-effective results.

Simon, Michael C.↗
NASA NTRS1989

Space biology initiative program definition review. Trade study 6: Space Station Freedom/spacelab modules compatibility

The differences in rack requirements for Spacelab, the Shuttle Orbiter, and the United States (U.S.) laboratory module, European Space Agency (ESA) Columbus module, and the Japanese Experiment Module (JEM) of Space Station Freedom are identified. The feasibility of designing standardized mechanical, structural, electrical, data, video, thermal, and fluid interfaces to allow space flight hardware designed for use in the U.S. laboratory module to be used in other locations is assessed.

Jackson, L. Neal↗
NASA NTRS1993

Protein crystallization aboard the Space Shuttle and the Mir space station

Two different protein crystallizations, namely ,the free Fab fragment of the Je142 monoclonal antibody and the complex of Fab fragment/HPr with antigen, were performed aboard the Discovery Space Shuttle flights and the Mir space station, respectively. Medium sized crystals of the Je142 Fab fragment were obtained. The Je142 Fab fragment/Hpr complex produced two medium-sized crystals after two months aboard the Mir space station. Microgravity was found to eliminate the tendency of these crystals to form clusters.

Delbaere, Louis T. J.↗
NASA NTRS1993

Limitations to the study of man in space in the U.S. space program

Research on humans conducted during spaceflight is fraught both with great opportunities and great obstacles. The purpose of this paper is to review some of the limitations to research in space in the United States with hope that an informed scientific community may lead to more rapid and efficient solution of these problems. Limitations arise because opportunities to study the same astronauts in well-controlled situations on repeated spaceflights are practically non-existent. Human research opportunities are further limited by the necessity of avoiding simultaneous mutually-interfering experiments. Environmental factors, including diet and other physiological perturbations concomitant with spaceflight, also complicate research design and interpretation. Technical limitations to research methods and opportunities further restrict the development of the knowledge base. Finally, Earth analogues of space travel all suffer from inadequacies. Though all of these obstacles will eventually be overcome, creativity, diligence, and persistence are required to further our knowledge of humans in space.

Bishop, Phillip A.↗
NASA NTRS1985

Interaction between the space transportation systems and the Space Station architecture and operations and technology requirements

This study, limited to the interaction between the Space Station and an orbital transfer vehicle, illustrates the need to include the space transportation system and the station in a synergistic analysis to determine an overall operationally efficient system that takes full advantage of the potential for the exploration and exploitation of space. Included are examples of the effects of the mission model on the selection of a possible orbit transfer vehicle design and processing procedures at the station; safe, timely, and flexible transfer vehicle trajectories from GEO to the station; mechanical assists on the station for vehicle arrivals and departures that reduce the risk of contamination and collision; and a discussion of the need for efficient procedures for vehicle maintenance and processing at the station.

Eide, Donald G.↗
NASA NTRS1993

In-space operations for lunar and Mars space transfer vehicles

The objective of this paper is to discuss the in-space operations required to process the lunar and Mars mission vehicles envisioned for the Space Exploration Initiative (SEI). Recent studies, which have examined the degree to which on-orbit operations change as a function of the Earth-to-orbit (ETO) launch vehicle size, identified a common set of on-orbit vehicle processing tasks, and generated functional requirements for in-space processing nodes are summarized in this paper. Timelines for on-orbit processing of two different lunar transfer vehicles (LTV's) were developed to compare a 'current practice,' labor-intensive EVA approach to ones utilizing telerobotics and advanced automation. LTV aerobrake concepts ranging from simple deployment to considerable assembly are compared. Similar timelines for the on-orbit processing of a nuclear Mars transfer vehicle (MTV) are also presented. Aerobrakes can be processed in a timely manner and should not be ruled out for SEI missions. The 'tall pole' time interval for on-orbit vehicle initial processing is the delivery of elements to orbit, not the processing tasks.

Raper, James L., Sr.↗
NASA NTRS1993

Space Life Sciences Research: The Importance of Long-Term Space Experiments

This report focuses on the scientific importance of long-term space experiments for the advancement of biological science and the benefit of humankind. It includes a collection of papers that explore the scientific potential provided by the capability to manipulate organisms by removing a force that has been instrumental in the evolution and development of all organisms. Further, it provides the scientific justification for why the long-term space exposure that can be provided by a space station is essential to conduct significant research.

Source record↗
NASA NTRS1991

Strategic plan, 1991: A strategy for leadership in space through excellence in space science and applications

In 1988, the Office of Space Science and Applications (OSSA) developed and published a Strategic Plan for the United States' space science and applications program during the next 5 to 10 years. The Plan presented the proposed OSSA program for the next fiscal year and defined a flexible process that provides the basis for near-term decisions on the allocation of resources and the planning of future efforts. Based on the strategies that have been developed by the advisory committees both of the National Academy of Sciences and of NASA, the Plan balances major, moderate, and small mission initiatives, the utilization of Space Station Freedom, and the requirements for a vital research base. The Plan can be adjusted to accommodate varying budget levels, both those levels that provide opportunities for an expanded science and applications program, and those that constrain growth. SSA's strategic planning is constructed around five actions: establish a set of programmatic themes; establish a set of decision rules; establish a set of priorities for missions and programs within each theme; demonstrate that the strategy can yield a viable program; and check the strategy for consistency with resource constraints. The outcome of this process is a clear, coherent strategy that meets both NASA's and OSSA's goals, that assures realism in long-range planning and advanced technology development, and that provides sufficient resiliency to respond and adapt to both known and unexpected internal and external realities. The OSSA Strategic Plan is revised annually to reflect the approval of new programs, improved understanding of requirements and issues, and any major changes in the circumstances, both within NASA and external to NASA, in which OSSA initiatives are considered.

Source record↗
NASA NTRS1993

Space Shuttle Mission STS-61: Hubble Space Telescope servicing mission-01

This press kit for the December 1993 flight of Endeavour on Space Shuttle Mission STS-61 includes a general release, cargo bay payloads and activities, in-cabin payloads, and STS-61 crew biographies. This flight will see the first in a series of planned visits to the orbiting Hubble Space Telescope (HST). The first HST servicing mission has three primary objectives: restoring the planned scientific capabilities, restoring reliability of HST systems and validating the HST on-orbit servicing concept. These objectives will be accomplished in a variety of tasks performed by the astronauts in Endeavour's cargo bay. The primary servicing task list is topped by the replacement of the spacecraft's solar arrays. The spherical aberration of the primary mirror will be compensated by the installation of the Wide Field/Planetary Camera-II and the Corrective Optics Space Telescope Axial Replacement. New gyroscopes will also be installed along with fuse plugs and electronic units.

Source record↗
NASA NTRS1994

Space tourism: A flight of fantasy or the next major space product? Paper session 3: Products

In the euphoria of the early 1980's, a number of creative proposals for nontraditional uses of space were suggested. Taking tourists to space, possibly as early as the 1990's, was one such proposal. While it is now obvious that wherever explorers go, tourists (and hoteliers, restauranteurs, and tour guides) will someday follow. This paper discusses past and present efforts to promote space as a tourist destination.

Stone, Barbara A.↗
NASA NTRS1993

Space history, space policy, and executive leadership

A lecture that attempts to establish the role of space historians in formulating space policy is presented. The discussion focusses on two adages and their relevance to space policy. The adages are as follows: 'write about what you know;' and 'good managers do things right; good executives do the right things.'

Kraemer, Sylvia K.↗
NASA NTRS1992

Modal survey testing of the Lidar In-space Technology Experiment (LITE) - A Space Shuttle payload

This paper presents the results of the modal survey test of the Lidar In-space Technology Experiment (LITE), a Space Shuttle payload mounted in a Spacelab flight single pallet. The test was performed by the Dynamics Test Branch at Marshall Space Flight Center, AL and run in two phases. In the first phase, an unloaded orthogrid connected to the pallet with 52 tension struts was tested. This test included 73 measurement points in three directions. In the second phase, the pallet was integrated with mass simulators mounted on the flight support structure to represent the dynamics (weight and center of gravity) of the various components comprising the LITE experiment and instrumented at 213 points in 3 directions. The test article was suspended by an air bag system to simulate a free-free boundary condition. This paper presents the results obtained from the testing and analytical model correlation efforts. The effect of the suspension system on the test article is also discussed.

Anderson, J. B.↗