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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 577 records · Page 32
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

TERSSE: Definition of the Total Earth Resources System for the Shuttle Era. Volume 5: Detailed system requirements: Two case studies

Major resource management missions to be performed by the TERSSE are examined in order to develop an understanding of the form and function of a system designed to perform an operational mission. Factors discussed include: resource manager (user) functions, methods of performing their function, the information flows and information requirements embodied in their function, and the characteristics of the observation system which assists in the management of the resource involved. The missions selected for study are: world crop survey and land resources management. These missions are found to represent opposite ends of the TERSSE spectrum and to support the conclusion that different missions require different systems and must be analyzed in detail to permit proper system development decisions.

Source record↗
NASA NTRS1974

TERSSE: Definition of the Total Earth Resources System for the Shuttle Era. Volume 7: User Models: A System Assessment

User models defined as any explicit process or procedure used to transform information extracted from remotely sensed data into a form useful as a resource management information input are discussed. The role of the user models as information, technological, and operations interfaces between the TERSSE and the resource managers is emphasized. It is recommended that guidelines and management strategies be developed for a systems approach to user model development.

Source record↗
NASA NTRS1975

Sensor development in the Shuttle era

The use of the Space Shuttle in the development of earth observation sensors is examined. Two sensor classes are selected for case histories: infrared temperature sounders and microwave radiometers. The most significant finding in each of the developmental studies of these two sensor classes is considered to be the feasibility and value of using the Shuttle/Spacelab as a test vehicle for the operation in space of a versatile multimode experimental sensor. The Shuttle Electrically Scanned Microwave Radiometer and the Shuttle Infrared Interferometer are found to be the most effective instruments in this context. The Shuttle/Spacelab Sortie mission characteristics provide opportunities for new approaches to the development of sensors, using the Shuttle as a test vehicle to improve the efficiency of the process with respect to time, cost, and/or quality of the final product. As for crew functions, the short-term Spacelab mission requires some near real-time evaluation of data quality and sensor function in order to insure efficient data collection.

Gerding, R. B.↗
NASA NTRS1975

Improved planetary orbit mission capabilities in the Shuttle era by use of space-storable propulsion systems

Planetary-orbit mission capabilities will be greatly improved by the advent of space-storable retropropulsion systems with liquid fluorine and hydrazine as bipropellants even when the Shuttle/Tug is used as launch vehicle. Having a specific impulse as large as 375 sec, a multimission propulsion module using space-storable propellants with Pioneer or Mariner spacecraft as payload can perform Mercury, Saturn, and Uranus orbiter missions, and even some comet rendezvous missions, more cost effectively and flexibly than one using earth-storable propellants. It also can reduce trip time to the outer planets significantly. This paper presents mission requirements, technology status, system design and performance, development schedules, and costs based on data derived in a recent design and feasibility study.

Meissinger, H. F.↗
NASA NTRS1976

A preliminary discussion of gravitational physics experiments for the Spacelab era

An overview of past, present, and proposed future experiments in gravitational physics is given. These experiments are concerned with the measurement of relativistic gravity effects to test theories of gravitation. Certain experiments which could be performed on shuttle and Spacelab missions and the potential of Spacelab for gravitation physics research are discussed.

Decher, R.↗
NASA NTRS1975

TERSSE. Definition of the total earth resources system for the shuttle era. Volume 9: Earth resources shuttle applications

The use of the space shuttle for the Earth Resources Program is discussed. Several problems with respect to payload selection, integration, and mission planning were studied. Each of four shuttle roles in the sortie mode were examined and projected into an integrated shuttle program. Several representative Earth Resources missions were designed which would use the shuttle sortie as a platform and collectively include the four shuttle roles. An integrated flight program based on these missions was then developed for the first two years of shuttle flights. A set of broad implications concerning the uses of the shuttle for Earth Resources studies resulted.

Alverado, U.↗
NASA NTRS1975

Spaceflight tracking and data network support in the space tug era

This paper describes the Spaceflight Tracking and Data Network (STDN) which will be used to provide command, telemetry and tracking support to the Space Tug in the 1980's. A description of the mission support capabilities of the two major elements of the STDN - the ground based sites (GSTDN) and the Tracking and Data Relay Satellite System (TDRSS) - is provided. This paper also contains a summary description of the mission/STDN RF and Data Handling interface.

Stelter, L. R.↗
NASA NTRS1976

Planetary missions in the Shuttle era

A conservative fifteen-year plan for planetary exploration is presented in which the Space Shuttle is considered as just a basic transportation system that should be quite economical and have excellent reliability. It is noted that these planned missions are limited by the out-of-orbit escape capability of the Shuttle's Interim Upper Stage (IUS), rather than by the orbital payload capability of the Shuttle itself. A mission model is provided in which a rather even balance is maintained among missions to the inner planets, the outer planets, the comets and asteroids, and interplanetary missions out of the ecliptic plane; the cost estimate for this model is plotted. Launch requirements for the various missions are compared with the performance available from various IUS candidates under evaluation, and it is shown that even the lower-performance candidates can be brought up to the capability of the current Titan IIIE/Centaur/TE-364 expendable launch vehicle, which is adequate for most of the missions in the program. Missions which require higher-performance IUS options are noted, including the Mariner Jupiter and Saturn Orbiters.

Kraemer, R. S.↗
NASA NTRS1975

Modular bus and payload designs for the Shuttle era

The Space Shuttle, in combination with the Interim Upper Stage, will provide an economical means of placing payloads in geostationary orbit in the 1980s. This paper summarizes a recent study of multidiscipline applications payloads for Shuttle-IUS launch. Various concepts for modular 'bus' spacecraft structures and payload groupings based on equipment commonality are considered. Several bus and payload configurations, ranging from 160 to 1600 kg, are developed. A typical payload is described in some detail. The payload consists of equipment at 400 MHz for search and rescue and data collection, at 1.5 and 15 GHz for aeronautical, maritime, and land mobile communications, at 40 and 90 GHz for millimeter wave communications, and at other bands for meteorological radiometry, electromagnetic environment measurements, and interferometry.

Durrani, S. H.↗
NASA NTRS1976

A new era of space transportation - Future programs

The Space Transportation System - Space Shuttle, Spacelab and Upper Stages - is described from the point of view of systems and operations. Future plans concerning the permanent occupancy of space are examined with emphasis on the Space Construction Base, Advanced Transportation Systems and Space Industrialization plans.

Yardley, J. F.↗
NASA NTRS1976

Shuttle era waste management and biowaste monitoring

The acquisition of crew biomedical data has been an important task on manned space missions. The monitoring of biowastes from the crew to support water and mineral balance studies and endocrine studies has been a valuable part of this activity. This paper will present a review of waste management systems used in past programs. This past experience will be cited as to its influence on the Shuttle design. Finally, the Shuttle baseline waste management system and the proposed Shuttle biomedical measurement and sampling systems will be presented.

Sauer, R. L.↗
NASA NTRS1977

Tracking system performance tests in the MDS era

Tracking system performance tests as developed to support DSN Mark III Data Subsystem implementation project and prepass readiness tests are described. The system test design, the rationale chosen for implementation, and the inevitable compromises imposed by schedule constraints and reserves are discussed.

Buckles, B. J.↗
NASA NTRS1976

Clays as possible catalysts for peptide formation in the prebiotic era

From the point of view of prebiotic synthesis, clays might have performed functions of concentration, catalysis, and protection of molecules. The degrees of polymerization obtained, when amino acid adenylates are added to montmorillonite suspensions in water, are much higher than those obtained by polymerization in the absence of such a clay. In addition, they are of a discrete spectrum, usually multiples of 6 or 7, and reach values of up to 40 mers. In the absence of clay a continuous spectrum of degrees of polymerization is obtained, and usually up to 4-6 mers only. Copolymerization in the absence of clays yields mostly random copolymers, in their presence mostly block copolymers are obtained. Optical density measurements show that after adsorption has taken place on the clay, stacking of its layers occurs. Polymerization starts only after these stacked layers have been formed

Paecht-Horowitz, M.↗
NASA NTRS1977

Opening a new era in space

The overall payload planning aimed at initial projected use of the Space Transportation System (STS) which will establish a new capability for exploring and using space through operations of the Shuttle, Spacelab, and Interim Upper Stage (IUS) in the Eighties is reviewed, and the significance of this planning for science and technology is discussed. The first payloads will fly on the STS during Orbital Flight Tests (OFT) beginning in March 1979. Primary OFT objectives include verifying flight systems and the Shuttle's ability to accomodate various types of payloads in different mission modes. The STS schedule will build up to as many as 60 flights in 1984. The STS payloads will make contributions to the management on a global scale of the interrelationship of production, consumption, population growth, and pollution.

Culbertson, P. E.↗
NASA NTRS1977

The Shuttle era - A challenge to the earth scientist

Satellite observations of large-scale earth features and phenomena, with either instruments or astronauts, are discussed on the basis of earlier experience (mainly Skylab). Off-nadir views and photographs by astronauts have provided valuable supplements to instrument nadir views, providing cross-checks through remote sensing at different angles, different altitudes, and in different seasons. New information on plate tectonics, global cooling/drying trends, global oceanographic data (changing positions of major ocean current patterns, evolution of warm and cold eddies and their relation to sea temperatures and concentrations of marine fauna, location of internal sea waves, interactions between ocean currents and atmosphere, plankton blooms), storm development, snow cover patterns, lake and sea ice growth, sand-dune patterns, desert storms blown out to sea, effects of grazing and swidden agriculture, and other earth features and phenomena are surveyed.

Muehlberger, W. R.↗
NASA NTRS1978

Cometary exploration in the shuttle era

A comprehensive program plan for cometary exploration in the 1980-2000 time frame is proposed. Plans for ground-based observations, a Spacelab cometary observatory, and the Space Telescope are included in the observational program. The cometary mission sequence begins with a dual-spacecraft flyby of Halley's comet. The nominal mission strategy calls for a simultaneous launch of two spacecraft towards an intercept with Halley in March 1986. After the Halley encounter, the spacecraft are retargeted: one to intercept comet Borrelly in January 1988 and the other to intercept comet Tempel-2 in September 1988. The additional cometary intercepts are accomplished by utilizing a novel Earth-swingby technique. The next mission in the cometary program plan, a rendezvous with Encke's comet, is scheduled for launch in early 1990. It is planned to rendezvous with Encke in September 1992 at a heliocentric distance of 4 AU. Following this near-aphelion rendezvous, the spacecraft will remain with with Encke through the next two perihelion passages in February 1994 and May 1997. The rendezvous mission will be terminated about seven months after the second perihelion passage.

Farquhar, R. W.↗
NASA NTRS1978

Evidence for a primordial magnetic field during the meteorite parent body era

Data on 247 meteorites were examined, and a log-log plot of the magnetic moment/gm versus the susceptibility/gm reveals a straight-line relation with a slope of unity for a range of meteorite types extending from achondrites at the low Fe-Ni end to stony-irons. The relation holds for a span of parameter values ranging between four and five orders. The results support the hypothesis of a common background magnetic field at the time of meteorite formation. An equation relating the primordial field strength to the average carrier demagnetization factor, which can vary from 0 to 4 pi, is presented. The extreme lower limit for the field strength is 0.02 oersted, while for the mean field of 0.27 oersted determined from a study of individual meteorites (Stacy and Banerjee, 1974), the average value for the carrier demagnetization factor is 0.74, corresponding to elongated grains.

Sonett, C. P.↗