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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 181 records · Page 10

Acceleration of electrons by interplanetary shocks

Ion acceleration is a well known phenomenon at both interplanetary shocks, while there have been only a few reports concerning an acceleration of electrons at interplanetary shocks. The considered investigation reports that electron acceleration occurs at many shocks. The instrumentation used is discussed, taking into account the ISEE 3 (International Sun Earth Explorer) spacecraft and the electrostatic analyzer employed for the measurement of electrons. Changes in the electron distribution function caused by shocks are found to be quite varied. Some events show a simple step to a higher flux level, some show fluctuations as the flux rises, and some have one or more pulses at the time of the shock. Attention is given to data obtained on July 26, 1979, December 25, 1978, and November 12, 1978. A calculation of shock geometries is also reported.

Potter, D. W.↗

Space station needs, attributes and architectural options study. Volume 1: Executive summary

Planetary explorations, Earth observations, space physics, astronomy-astrophysics, solar physics, life/biological/medical sciences, materials processing in space, communications, and technology development are addressed. Mission requirements, integrated user requirements, and space station user accommodation requirements are discussed. Mission implementation concepts and cost, benefits and programmatic analysis are discussed.

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Data from ISEE-3 for the IMS period

The International Sun-Earth Explorer (ISEE) Project represents a joint effort between the European Space Agency and NASA. The primary objective of the project is the study of the outer magnetosphere. A review is presented concerning the data available from ISEE-3 up to the end of the International Magnetospheric Study (IMS) period (December 31, 1979), taking into account the approaches used to obtain the data. Attention is given to the ISEE-3 as an upstream monitor, ISEE-3 an an observer of the magnetosphere, aspects of ISEE-3 data availability, questions regarding the data link, and the definitive orbit position of ISEE-3 throughout the IMS.

Von Rosenvinge, T. T.↗

Radio evidence for interplanetary streamers in the range 10-170 solar radii

Type III radio storms are observed by the radio experiment on board the International Sun Earth Explorer 3 out to 0.5-0.8 AU from the Sun, at a rate of 2 to 3 storms per solar rotation near solar maximum. They correlate with the type I and type III radio storms observed at higher frequencies, originating closer to the Sun. They are associated with an almost continuous injection of suprathermal electrons into the interplanetary medium. Some of the properties of the regions where the particles propagate are discussed, using the radio emission as a tracer.

Fainberg, J.↗

ISEE-3 Microwave Filter Requirements

The 64 m subnet is committed to support the International Sun Earth Explorer (ISEE-3) spacecraft. The uplink and one of the downlink frequencies will be respectively, 2090 and 2217 MHz. As these two frequencies fall outside the normal DSN transmit and receive bands, the 64-m antennas present new filter requirements, which are analyzed.

Galvez, J. L.↗

Hot plasma composition results from the ISEE-1 spacecraft

The International Sun Earth Explorer (ISEE-1) was launched on Oct. 22, 1977 into a geocentric elliptical orbit. The energetic ion mass spectrometer on the satellite is employed in a study of the plasmas encountered by ISEE-1 in its orbits. The experiment is operating successfully and research is progressing in a number of areas. A review in the nature of a progress report on the energetic magnetospheric plasma results is provided. Attention is given to the plasma sheet and ion streams in the magnetotail, the inner magnetosphere, and magnetospheric boundary regions.

Sharp, R. D.↗

Isotopic composition of primary cosmic rays H-Fe for ISEE-C

The high energy cosmic ray instrument built for the International Sun-Earth Explorer is described. Some aspects of that system are critically renewed so that the experience gained in the design, construction and operation of this experiment can serve as a guide in designing future cosmic ray particle identification systems.

Heckman, H. H.↗

NASA Space controls research and technology program

The NASA technological organization is outlined. The Office of Aeronautics and Space Technology (OAST) is one of the four major technical offices that comprise NASA. The Office of Space Science and Applications administers programs directed towards using space-based or related techniques to further understanding of the total universe and to apply that understanding to practical applications in such areas as Astrophysics, Solar System exploration, Earth Sciences, Life Sciences, Communications and Information Systems. The Office of Space Flight administers the programs for all U.S. civil launch capability, plus Spacelab development and operations. The Office of Space Tracking & Data Systems administers the programs that operate and maintain a world-wide network of facilities for data acquisition, processing, and ground to spacecraft communications for all NASA missions. The OAST has primary responsibility within NASA for conducting space research and technology development to support commercial and military as well as NASA space interests.

Mciver, D. E.↗

A second catalog of gamma ray bursts: 1978 - 1980 localizations from the interplanetary network

Eighty-two gamma ray bursts were detected between 1978 September 14 and 1980 February 13 by the experiments of the interplanetary network (Prognoz 7, Venera 11 and 12 SIGNE experiments, Pioneer Venus Orbiter, International Sun-Earth Explorer 3, Helios 2, and Vela). Sixty-five of these events have been localized to annuli or error boxes by the method of arrival time analysis. The distribution of sources is consistent with isotropy, and there is no statistically convincing evidence for the detection of more than one burst from any source position. The localizations are compared with those of two previous catalogs.

Atteia, J. L.↗

The isotopic composition of cosmic ray chlorine

The isotopic composition of galactic cosmic ray chlorine (approx. = 225 MeV/amu) has been studied using the high energy cosmic ray experiment on the International Sun Earth Explorer 3 (ISEE-3) spacecraft. The abundances of 35C1 and 37C1 are found to be consistent with the secondary production expected from a propagation model developed to account for both light and subiron secondaries. An upper limit on the abundance of the radioactive isotope 36C1 (halflife approx. = 0.3 Myr) is used to set a lower limit on the confinement time of cosmic rays of approximately 1 Myr.

Wiedenbeck, M. E.↗

The isotopic composition of cosmic ray calcium

Data from the high energy cosmic ray experiment on the international sun earth explorer 3 (ISEE-3) spacecraft have been used to study the isotopic composition of cosmic ray calcium at an energy of approx. 260 MeV/amu. The arriving calcium is found to consist of (32 + or - 6)%. A propagation model consistent with both the light and the subiron secondary element abundances was used for the interpretation of the observed calcium composition. The measured 42Ca+43Ca+44Ca abundance is consistent with the calculated secondary production, while the 40Ca abundance implies a source ratio of 40Ca/Fe = (7.0 + or - 1.7)%.

Krombel, K. E.↗

The energy spectra of solar flare electrons

A survey of 50 electron energy spectra from .1 to 100 MeV originating from solar flares was made by the combination of data from two spectrometers onboard the International Sun Earth Explorer-3 spacecraft. The observed spectral shapes of flare events can be divided into two classes through the criteria of fit to an acceleration model. This standard two step acceleration model, which fits the spectral shape of the first class of flares, involves an impulsive step that accelerates particles up to 100 keV and a second step that further accelerates these particles up to 100 MeV by a single shock. This fit fails for the second class of flares that can be characterized as having excessively hard spectra above 1 MeV relative to the predictions of the model. Correlations with soft X-ray and meter radio observations imply that the acceleration of the high energy particles in the second class of flares is dominated by the impulsive phase of the flares.

Evenson, P. A.↗

Energetic protons from a disappearing solar filament

A solar energetic (E 50 MeV) particle (SEP) event observed at 1 AU began about 15000 UT on 1981 December 5. This event was associated with a fast coronal mass ejection observed with the Solwind coronagraph on the P78-1 satellite. No metric type 2 or type 4 burst was observed, but a weak interplanetary type 2 burst was observed with the low frequency radio experiment on the International Sun-Earth Explorer-3 satellite. The mass ejection was associated with the eruption of a large solar quiescent filament which lay well away from any active regions. The eruption resulted in an H alpha double ribbon structure which straddled the magnetic inversion line. No impulsive phase was obvious in either the H alpha or the microwave observations. This event indicates that neither a detectable impulsive phase nor a strong or complex magnetic field is necessary for the production of energetic ions.

Kahler, S. W.↗

Characteristics of the white-light source in the 1981 April 24 solar flare

Observations of the white-light solar flare event of April 24, 1981 are presented. The observations were carried out in the optical, hard X-ray, and radio wavelengths from land-based observatories and from the International Sun-Earth Explorer (ISEE-3) satellite. Time-intensity profiles were derived for three lines of continuum emissions. The derived profiles are interpreted in terms of the energetics of the flare, and the role of energetic electrons in the production of optical continuum emission is examined in detail.

Kane, S. R.↗

Particle acceleration by the sun

A review is given of the analysis of new observations of energetic particles and energetic secondary emissions obtained over the solar maxium (approx. 1980) by the Solar Maximum mission, Hinotori, the international Sun-Earth Explorer, Helios, Explorer satellites, and Voyager spacecraft. Solar energetic particle events observed in space, He(3)- rich events, solar gamma rays and neutrons, and solar neutrinos are discussed.

Lin, R. P.↗

Three-dimensional plasma observations near the outer magnetospheric boundary

The present study is concerned with an evaluation of some of the plasma and field processes by which the magnetospheric boundary layer acts as a magnetohydrodynamic (HD) dynamo. An analysis is conducted of 18 crossings of the dayside magnetopause and boundary layer, taking into account data provided by the quadrispherical electrostatic analyzers (Lepedea) of the International Sun-Earth Explorer (ISEE) spacecraft. These instruments sample ion and electron velocity distributions in three dimensions. Attenion is given to aspects of data presentation, magnetopause identification, details regarding the magnetopause crossings, cross-field plasma flow, comparisons of magnetosheath and boundary layer plasma flow, and six conclusions.

Eastman, T. E.↗

The handling of data in solar-terrestrial and in planetary physics

The evolution of data handling systems for solar-terrestrial and planetary physics applications is discussed. The main elements of data management systems for scientific satellites are described, including: command and control; data transmission; prioritization of data users; and data reduction and analysis. The design approaches incorporated into the data management systems of the Interplanetary Monitoring Platform (IMP), International Sun Earth Explorer (ISEE), and the Orbiting Geophysical Observatory, (OGO) spacecraft, are discussed. Emphasis is given to classical, centralized, and hybrid system designs. The report of the Committee on Data Management and Computation (CODMAC) concerning concepts for new data management systems is briefly summarized.

Vette, J. I.↗

Satellite operations support expert system

The Satellite Operations Support Expert System is an effort to identify aspects of satellite ground support activity which could profitably be automated with artificial intelligence (AI) and to develop a feasibility demonstration for the automation of one such area. The hydrazine propulsion subsystems (HPS) of the International Sun Earth Explorer (ISEE) and the International Ultraviolet Explorer (IUS) were used as applications domains. A demonstration fault handling system was built. The system was written in Franz Lisp and is currently hosted on a VAX 11/750-11/780 family machine. The system allows the user to select which HPS (either from ISEE or IUE) is used. Then the user chooses the fault desired for the run. The demonstration system generates telemetry corresponding to the particular fault. The completely separate fault handling module then uses this telemetry to determine what and where the fault is and how to work around it. Graphics are used to depict the structure of the HPS, and the telemetry values displayed on the screen are continually updated. The capabilities of this system and its development cycle are described.

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