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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 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
NASA NTRS1993

A comparison of low-gravity measurements on-board Columbia during STS-40

The first NASA Spacelab Life Sciences mission (SLS-1) flew 5 June to 14 June 1991 on the orbiter Columbia (STS-40). The purpose of the mission was to investigate the human body's adaptation to the low-gravity conditions of space flight and the body's readjustment after the mission to the 1g environment of earth. In addition to the life sciences experiments manifested for the Spacelab module, a variety of experiments in other scientific disciplines flew in the Spacelab and in Get Away Special (GAS) Canisters on the GAS Bridge Assembly. Several principal investigators designed and flew specialized accelerometer systems to better assess the results of their experiments by means of a low-gravity environment characterization. This was also the first flight of the NASA Microgravity Science and Applications Division (MSAD) sponsored Space Acceleration Measurement System (SAMS) and the first flight of the NASA Orbiter Experiments Office (OEX) sponsored Orbital Acceleration Research Experiment accelerometer (OARE). We present a brief introduction to seven STS-40 accelerometer systems and discuss and compare the resulting data. During crew sleep periods, acceleration magnitudes in the 10(exp -6) to 10(exp -5)g range were recorded in the Spacelab module and on the GAS Bridge Assembly. Magnitudes increased to the 10(exp -4) level during periods of nominal crew activity. Vernier thruster firings caused acceleration shifts on the order of 10(exp -4)g and primary thruster firings caused accelerations as great as 10(exp -2) g. Frequency domain analysis revealed typical excitation of Orbiter and Spacelab structural modes at 3.5, 4.7, 5.2, 6.2, 7, and 17 Hz.

Rogers, M. J. B.↗
NASA NTRS1989

Microgravity research in NASA ground-based facilities

An overview of reduced gravity reasearch performed in NASA ground-based facilities sponsored by Microgravity Science and Applications Program of the NASA Office of Space Science and Applications is presented. A brief description and summary of the operations and capabilities of each of these facilities along with an overview of the historical usage of them is included. The goals and program elements of the Microgravity Science and Applications programs are described and the specific programs that utilize the low gravity facilities are identified. Results from two particular investigations in combustion (flame spread over solid fuels) and fluid physics (gas-liquid flows at microgravity conditions) are presented.

Lekan, Jack↗
NASA NTRS1993

A comparison of low-gravity measurements on-board Columbia during STS-40

The first NASA Spacelab Life Sciences mission (SLS-1) flew 5 Jun. to 14 Jun. 1991 on the orbiter Columbia (STS-40). The purpose of the mission was to investigate the human body's adaptation to the low-gravity conditions of space flight and the body's readjustment after the mission to the 1 g environment of earth. In addition to the life sciences experiments manifested for the Spacelab module, a variety of experiments in other scientific disciplines flew in the Spacelab and in Get Away Special (GAS) Canisters on the GAS Bridge Assembly. Several principal investigators designed and flew specialized accelerometer systems to better assess the results of their experiments by means of a low-gravity environment characterization. This was also the first flight of the NASA Microgravity Science and Applications Division (MSAD) sponsored Space Acceleration Measurement System (SAMS) and the first flight of the NASA Orbiter Experiments Office (OEX) sponsored Orbital Acceleration Research Experiment accelerometer (OARE). A brief introduction to seven STS-40 accelerometer systems are presented and the resulting data are discussed and compared. During crew sleep periods, acceleration magnitudes in the 10(exp -6) to 10(exp -5) g range were recorded in the Spacelab module and on the GAS Bridge Assembly. Magnitudes increased to the 10(exp -4) g level during periods of nominal crew activity. Vernier thruster firings caused acceleration shifts on the order of 10(exp -4) g and primary thruster firings caused accelerations as great as 10(exp -2) g. Frequency domain analysis revealed typical excitation of Orbiter and Spacelab structural modes at 3.5, 4.7, 5.2, 6.2, 7, and 17 Hz.

Rogers, Melissa J. B.↗
NASA NTRS1986

Life Sciences Space Station planning document: A reference payload for the Life Sciences Research Facility

The Space Station, projected for construction in the early 1990s, will be an orbiting, low-gravity, permanently manned facility providing unprecedented opportunities for scientific research. Facilities for Life Sciences research will include a pressurized research laboratory, attached payloads, and platforms which will allow investigators to perform experiments in the crucial areas of Space Medicine, Space Biology, Exobiology, Biospherics and Controlled Ecological Life Support System (CELSS). These studies are designed to determine the consequences of long-term exposure to space conditions, with particular emphasis on assuring the permanent presence of humans in space. The applied and basic research to be performed, using humans, animals, and plants, will increase our understanding of the effects of the space environment on basic life processes. Facilities being planned for remote observations from platforms and attached payloads of biologically important elements and compounds in space and on other planets (Exobiology) will permit exploration of the relationship between the evolution of life and the universe. Space-based, global scale observations of terrestrial biology (Biospherics) will provide data critical for understanding and ultimately managing changes in the Earth's ecosystem. The life sciences community is encouraged to participate in the research potential the Space Station facilities will make possible. This document provides the range and scope of typical life sciences experiments which could be performed within a pressurized laboratory module on Space Station.

Source record↗
NASA NTRS1993

Low gravity environment on-board Columbia during STS-40

The first NASA Spacelab Life Sciences mission (SLS-I) flew 5 June to 14 June 1991 on the orbiter Columbia (STS-40). The purpose of the mission was to investigate the human body's adaptation to the low gravity conditions of space flight and the body's readjustment after the mission to the 1 g environment of earth. In addition to the life sciences experiments manifested for the Spacelab module, a variety of experiments in other scientific disciplines flew in the Spacelab and in Get Away Special (GAS) Canisters on the GAS Bridge Assembly. Several principal investigators designed and flew specialized accelerometer systems to characterize the low gravity environment. This was done to better assess the results of theft experiments. This was also the first flight of the NASA Microgravity Science and Applications Division (MSAD) sponsored Space Acceleration Measurement System (SAMS) and the first flight of the NASA Orbiter Experiments Office (OEX) sponsored Orbital Acceleration Research Experiment accelerometer (OARE). We present a brief introduction to seven STS-40 accelerometer systems and discuss and compare the resulting data.

Rogers, M. J. B.↗
NASA NTRS1991

The Biological Flight Research Facility

NASA Ames Research Center is building a research facility, the Biological Flight Research Facility (BFRF), to meet the needs of life scientists to study the long-term effects of variable gravity on living systems. The facility will be housed on Space Station Freedom and is anticipated to operate for the lifetime of the station, approximately 30 years. It will allow plant and animal biologists to study the role of gravity, or its absence, at varying gravity intensities for varying periods of time and with various organisms. The principal difference between current Spacelab missions and those on Space Station Freedom, other than length of mission, will be the capability to perform on-orbit science procedures and the capability to simulate earth gravity. Initially, the facility will house plants and rodents in habitats which can be maintained at microgravity or can be placed on a 2.5-m diam centrifuge. However, the facility is also being designed to accommodate future habitats for small primates, avian, and aquatic specimens. The centrifuge will provide 1 g for controls and will also be able to provide gravity from 0.01 to 2.0 g for threshold gravity studies as well as hypergravity studies. The BFRF will provide the means to conduct basic experiments to gain an understanding of the effects of microgravity on the structure and function of plants and animals, as well as investigate the role of gravity as a potential countermeasure for the physiological changes observed in microgravity.

Johnson, Catherine C.↗
NASA NTRS1993

The Biological Flight Research Facility

NASA Ames Research Center (ARC) is building a research facility, the Biological Flight Research Facility (BFRF), to meet the needs of life scientists to study the long-term effects of variable gravity on living systems. The facility will be housed on Space Station Freedom and is anticipated to operate for the lifetime of the station, approximately thirty years. It will allow plant and animal biologists to study the role of gravity, or its absence, at varying gravity intensities for varying periods of time and with various organisms. The principal difference between current Spacelab missions and those on Space Station Freedom, other than length of mission, will be the capability to perform on-orbit science procedures and the capability to simulate earth gravity. Initially the facility will house plants and rodents in habitats which can be maintained at microgravity or can be placed on a 2.5 meter diameter centrifuge. However, the facility is also being designed to accommodate future habitats for small primates, avian, and aquatic specimens. The centrifuge will provide 1 g for controls and will also be able to provide gravity from 0.01 to 2.0 g for threshold gravity studies as well as hypergravity studies. Included in the facility are a service unit for providing clean chambers for the specimens and a glovebox for manipulating the plant and animal specimens and for performing experimental protocols. The BFRF will provide the means to conduct basic experiments to gain an understanding of the effects of microgravity on the structure and function of plants and animals, as well as investigate the role of gravity as a potential countermeasure for the physiological changes observed in microgravity.

Johnson, Catherine C.↗
NASA NTRS2015

ARTEMIS Lunar Orbit Insertion and Science Orbit Design Through 2013

As of late-July 2011, the ARTEMIS mission is transferring two spacecraft from Lissajous orbits around Earth-Moon Lagrange Point #1 into highly-eccentric lunar science orbits. This paper presents the trajectory design for the transfer from Lissajous orbit to lunar orbit insertion, the period reduction maneuvers, and the science orbits through 2013. The design accommodates large perturbations from Earth's gravity and restrictive spacecraft capabilities to enable opportunities for a range of heliophysics and planetary science measurements. The process used to design the highly-eccentric ARTEMIS science orbits is outlined. The approach may inform the design of future planetary moon missions.

lunar orbiters↗
NASA NTRS1989

Microgravity research in NASA ground-based facilities

An overview of reduced gravity research performed in NASA ground-based facilities sponsored by the Microgravity Science and Applications Program of the NASA Office of Space Science and Applications is presented. A brief description and summary of the operations and capabilities of each of these facilities along with an overview of the historical usage of them is included. The goals and program elements of the Microgravity Science and Applications programs are described and the specific programs that utilize the low gravity facilities are identified. Results from two particular investigations in combustion (flame spread over solid fuels) and fluid physics (gas-liquid flows at microgravity conditions) are presented.

Lekan, Jack↗
NASA NTRS1989

The gravity probe B relativity gyroscope program

The idea of testing general relativity through observations on Earth orbiting gyroscopes was suggested in 1959 to 1960. The direction, it was noted, of spin of a suitably oriented gyroscope should change with respect to the line of sight to a guide star for two reasons: a geodetic effect from the motion of the gyroscope through the curved space-time around the Earth, and a frame-dragging effect from the Earth's rotation. NASA began supporting laboratory research on the experiment, now called Gravity Probe B, in 1964. Technologies for it were progressively established, and an error analysis demonstrated the potential of measuring frame-dragging to 1 to 2 percent and the geodetic effect to 1 part in 10(exp 4). Later analyses, discussed herein, suggest possibilities for further improving those precisions each by a further factor of 10. In 1984, after technical and scientific reviews by the Space Science Board and other bodies, and completion by NASA Marshall Center of a Phase B Study, the NASA Administrator approved the start of a program known as STORE (Shuttle Test Of the Relativity Experiment). The purpose of STORE is to verify the final Gravity Probe B science payload, perform on the Shuttle a 7-day experiment rehearsal (including sophisticated gyro tests in low gravity), and then return the payload to Earth for refurbishment and integration into the Science Mission spacecraft. The payload comprises four gyroscopes, a telescope, and a drag-free proof mass, all mounted in a quartz block assembly within an evacuated magnetically shielded probe, which in turn is inserted into a 10-ft long, 6-ft diameter liquid helium dewar, operating at 1.8 K and maintaining low temperature for 2 years. STORE is manifested on Shuttle OV-105, for launch MSSN 69 in February 1993. The Science Mission is set tentatively for June 1995.

Everitt, C. W. Francis↗
NASA NTRS1987

Spacelab 3 Mission Science Review

Papers and abstracts of the presentations made at the symposium are given as the scientific report for the Spacelab 3 mission. Spacelab 3, the second flight of the National Aeronautics and Space Administration's (NASA) orbital laboratory, signified a new era of research in space. The primary objective of the mission was to conduct applications, science, and technology experiments requiring the low-gravity environment of Earth orbit and stable vehicle attitude over an extended period (e.g., 6 days) with emphasis on materials processing. The mission was launched on April 29, 1985, aboard the Space Shuttle Challenger which landed a week later on May 6. The multidisciplinary payload included 15 investigations in five scientific fields: material science, fluid dynamics, life sciences, astrophysics, and atmospheric science.

Fichtl, George H.↗
NASA NTRS1990

Compatibility of the Space Station Freedom life sciences research centrifuge with microgravity requirements

NASA is developing a Life Sciences Centrifuge Facility for Space Station Freedom. In includes a 2.5-meter artificial gravity Bioresearch Centrifuge (BC), which is perhaps the most critical single element in the life sciences space research program. It rotates continuously at precise selectable rates, and utilizes advanced reliable technologies to reduce vibrations. Three disturbance types are analyzed using a current Space Station Freedom dynamic model in the 0.0 to 5.0 Hz range: sinusoidal, random, and transient. Results show that with proper selection of proven design techniques, BC vibrations are compatible with requirements.

Hasha, Martin D.↗
NASA NTRS1985

Applications of Tethers in Space, Volume 2

Topics discussed include tethered satellites, tether deployment, satellite systems, science applications, electrodynamic interactions, transportation applications, artificial gravity, constellations, and technology and testing.

Cron, A. C.↗
NASA NTRS1986

Applications of Tethers in Space: Workshop Proceedings, Volume 1

The complete documentation of the workshop including all addresses, panel reports, charts, and summaries are presented. This volume presents all the reports on the fundamentals of applications of tethers in space. These applications include electrodynamic interactions, transportation, gravity utilization, constellations, technology and test, and science applications.

Baracat, W. A.↗
NASA NTRS1989

The role of the Space Station in the further exploration of space

Plans for space-science experiments on the International Space Station (ISS) are reviewed, with a focus on biological and medical research with implications for manned missions to the moon and planets (in a scenario culminating in the establishment of a space colony by about the year 2018). Both applied biomedical research (determining the limits of human endurance in space and developing CELSS technology to extend them) and basic research (on the physiological response of plants and animals to the space environment) are discussed, and particular attention is given to the design and deployment schedule for the ISS biomedical hardware modules (Life Sciences Module, Centrifuge Module, and Variable-Gravity Research Facility). Also included are diagrams; drawings; photographs; and tables listing the individual experiments, their objectives, and the hardware required.

Bonting, S. L.↗
NASA NTRS1992

Long-term effects of microgravity and possible countermeasures

The measures that can be taken to counteract the effect of long-term exposures to microgravity are discussed. It is noted that, although it was shown that specially designed exercise programs can counteract the effect of exposures of up to one year in space, is it questionable whether U.S. astronauts could or should have to maintain such regimes for extremely prolonged missions. The methods considered by NASA Life Sciences Division are to provide an artificial gravity environment by the generation of centrifugal forces by means of either the continuous rotation of the whole spacecraft or using a short-arm centrifuge on board a zero-g spacecraft. Results obtained in studies of these two methods are discussed, and the centrifuge research facility that is presently being developed by NASA is described.

Wolfe, James W.↗
NASA NTRS1992

Measurements of a deep space station fractional frequency stability to the 10 exp -15 level

This article presents techniques for measuring frequency stability of a deep space station that was configured with a new X-band transmitter subsystem to enable high-quality radio science data to be obtained for a Gravity Wave Experiment. The instrument and test procedures for performing frequency stability measurements in the field are described. Test results from measurements made on various transmit receive subsystems, as well as the overall transmit-receive end-to-end systems below the antenna feed horn are presented. The subsystem test data proved to be useful for assessing the frequency stabilities of various subsystems. This assessment design improvements needed to meet stringent frequency stability requirements for forthcoming gravity wave experiments.

Otoshi, Tom Y.↗