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Jaffe, L.

Publications and source records attributed to Jaffe, L..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1988

Nuclear reactor power as applied to a space-based radar mission

The SP-100 Project was established to develop and demonstrate feasibility of a space reactor power system (SRPS) at power levels of 10's of kilowatts to a megawatt. To help determine systems requirements for the SRPS, a mission and spacecraft were examined which utilize this power system for a space-based radar to observe moving objects. Aspects of the mission and spacecraft bearing on the power system were the primary objectives of this study; performance of the radar itself was not within the scope. The study was carried out by the Systems Design Audit Team of the SP-100 Project.

Jaffe, L.↗
NASA NTRS1988

Nuclear reactor power as applied to a space-based radar mission

A space-based radar mission and spacecraft are examined to determine system requirements for a 300 kWe space nuclear reactor power system. The spacecraft configuration and its orbit, launch vehicle, and propulsion are described. Mission profiles are addressed, and storage in assembly orbit is considered. Dynamics and attitude control and the problems of nuclear and thermal radiation are examined.

Jaffe, L.↗
NASA NTRS1988

Systems aspects of a space nuclear reactor power system

Various system aspects of a 300-kW nuclear reactor power system for spacecraft have been investigated. Special attention is given to the cases of a reusable OTV and a space-based radar. It is demonstrated that the stowed length of the power system is important to mission design, and that orbital storage for months to years may be needed for missions involving orbital assembly.

Jaffe, L.↗
NASA NTRS1987

Nuclear reactor power for an electrically powered orbital transfer vehicle

To help determine the systems requirements for a 300-kWe space nuclear reactor power system, a mission and spacecraft have been examined which utilize electric propulsion and this nuclear reactor power for multiple transfers of cargo between low earth orbit (LEO) and geosynchronous earth orbit (GEO). A propulsion system employing ion thrusters and xenon propellant was selected. Propellant and thrusters are replaced after each sortie to GEO. The mass of the Orbital Transfer Vehicle (OTV), empty and dry, is 11,000 kg; nominal propellant load is 5000 kg. The OTV operates between a circular orbit at 925 km altitude, 28.5 deg inclination, and GEO. Cargo is brought to the OTV by Shuttle and an Orbital Maneuvering Vehicle (OMV); the OTV then takes it to GEO. The OTV can also bring cargo back from GEO, for transfer by OMV to the Shuttle. OTV propellant is resupplied and the ion thrusters are replaced by the OMV before each trip to GEO. At the end of mission life, the OTV's electric propulsion is used to place it in a heliocentric orbit so that the reactor will not return to earth. The nominal cargo capability to GEO is 6000 kg with a transit time of 120 days; 1350 kg can be transferred in 90 days, and 14,300 kg in 240 days. These capabilities can be considerably increased by using separate Shuttle launches to bring up propellant and cargo, or by changing to mercury propellant.

Jaffe, L.↗
NASA NTRS1980

Eyewitness report on Chinese satellite work

The article describes the current status of satellite and related technology in the People's Republic of China. Attention is given to areas of potential cooperation and scientific and technical 'exchanges'. It is reported that the Chinese technology is 'advanced, but simple' and that the Chinese showed great interest in receiving U.S. technical know-how.

Edelson, B.↗
NASA NTRS1978

Switchboard in the sky

Geostationary parking orbits for the present generation of communications satellites, e.g., Intelsat, Westar, Molniya, Navsat, etc., are becoming crowded. It is noted that the C-band over North America will in future be subject to still less attenuation with the introduction of smaller (4.5 m) antennas for earth-bound receive-only applications. It is suggested, at least for the present, that more bands be added, e.g., K-, Ku-, and S-bands. To handle the potential market for communications satellite services during the years after 1985, much larger facilities will be needed. The fabrication of large platforms using the STS is discussed as the most practical solution, stressing that virtually every geosynchronous communications antenna for U.S. domestic use can be assembled on one platform positioned at an especially favorable location.

Fordyce, S. W.↗
NASA NTRS1974

The United States earth resources survey program and ERTS experiments benefit highlights

With the launch of the first Earth Resources Technology Satellite in July 1972 a major new tool has become available for decision making in the assessment, exploitation, and management of the earth's resources on a national and international basis. The current status of the earth resources survey program is discussed and the future potential is reviewed. The supportive roles of all stages of the system, including surface, aircraft, and satellite components are noted. Specific cases of application of ERTS data are presented together with a discussion of benefits that might accrue. Need for cooperative, coordinated efforts between participants is emphasized.

Jaffe, L.↗
NASA NTRS1971

NASA earth resources satellite research and development program.

The NASA Earth Resources Survey (ERS) Program is discussed as an effort to augment the presently used ground techniques and limited aerial photography for obtaining larger survey data. The topics include the scientific and technological aspects of remote earth resources sensing, the past and present activities in this field, the immediate plans for the implementation of the program, and a summary of current and future international participation in it. The effective target areas of space observations under the program are listed as synoptic surveys, agriculture and forestry, geography, geology and mineral resources, hydrology and water resources, and marine resources. Acquisition of near real-time information, reduced data acquisition time, repeated coverage, measurement uniformity, global surveys without large on-site support requirements are indicated as the advantages of space observations.

Jaffe, L.↗
NASA NTRS1967

Commercial spacecraft technology survey.

Commercial spacecraft technology, discussing requirements for navigation/traffic control, voice broadcast, earth resources survey and Applications Technology Satellites

Jaffe, L.↗
NASA NTRS1966

Communications in space.

Book on communications satellites design, testing, operation and power systems for Echo, Telstar, Relay, Syncom, ground stations, etc

COMMUNICATIONS SATELLITE↗